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Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XL | Pages 131 - 131
1 Sep 2012
Mizokawa S Oonishi H Oonishi H Kyomoto M Iwamoto M Takano Y Ueno M
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Different types of highly cross-linked polyethylene (HXLPE) have been introduced widely in acetabular cups in hip prostheses to reduce the incidence of wear debris-induced osteolysis. Also, we reported that HXLPE cups with 28-mm alumina ceramic femoral head exhibited lower wear than conventional PE cups. Recently, the combination of HXLPE cup and larger diameter femoral head is used widely to prevent dislocation. In this study, we examined the wear of HXLPE with 32-mm alumina ceramic femoral head and compared it with the wear of HXLPE with 28-mm alumina ceramic femoral head. The in vivo wear of 60 HXLPE cups (Aeonian; Kyocera Corp., Kyoto, Japan, currently Japan Medical Materials Corp., Osaka, Japan) with 28-mm alumina ceramic femoral head with clinical use for 3.1–9.1 years (mean 7.4 years) and eight HXLPE cups with 32-mm alumina ceramic femoral head used for 2.3–3.2 years (mean 2.8 years) were examined by radiographic analysis. The early wear rate for the first year of HXLPE cups with 28-mm and 32-mm alumina ceramic femoral head were 0.24±0.10 mm/year and 0.29±0.12 mm/year respectively. There was no significant difference in both femoral head groups (p>0.05). The steady wear rate after 1 year were 0.001±0.03 mm/year and −0.03±0.10 mm/year respectively. There was no significant difference either in both femoral head groups (p>0.05). These findings from this radiographic analysis suggest that the early wear rate in the first 1 year probably represents the creep deformation in bedding-in stage; and the steady wear rate after 1 year probably represents mainly the wear than of the creep deformation. By the radiographic analysis, HXLPE cups in both femoral head groups exhibited low steady wear rate. In conclusion, we expect that the combination of HXLPE cup and 32-mm diameter alumina ceramic femoral head has favorable wear properties with possibility of prevention of dislocation in long-term clinical use


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 139 - 140
1 Mar 2010
Oonishi H Kim S Kyomoto M Iwamoto M Ueno M Oonishi H
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Aseptic loosening induced by wear debris of polyethylene (PE) is the most common cause of long-term total hip arthroplasty failure. In the previous studies, we reported that the protruding contour and surface morphology of metallic femoral head brought an increase of PE wear. Alumina ceramics is advantageous (neutral shape and smooth surface) for precision machining compared with metal materials, because hardness of ceramics is higher than that of metal materials. In this study, we measured the roundness and the roughness of retrieved alumina ceramic and metallic heads, aiming to evaluate the change of surface morphology of those heads in vivo. Fourteen retrieved alumina ceramic femoral heads (Kyocera Corp., currently Japan Medical Materials Corp.) were examined: ten femoral heads were made of small grain-size alumina ceramic (SG-alumina; mean grain size is 3.4 um) with a diameter of 28 mm, with clinical use for 16–28 years (mean 22 years) and four femoral head was made of extra-small-grain size alumina ceramic (XSG-alumina; mean grain size is 1.3 um) with a diameter of 26 mm, with clinical use for 14–19 years (mean 16 years). Six retrieved metallic femoral heads with average clinical use for 12–28 years (mean 18 years) were examined: a diameter of from 22 to 32 mm (e.g. Zimmer Inc., Stryker Corp.) The roundness of the retrieved femoral heads was measured by a contour tracer. The surface roughness in the contact area and the non-contact area of the retrieved femoral heads was measured by a surface roughness tester. Out-of-roundness of SG-alumina and XSG-alumina heads was 0.15 um and 0.19 um, respectively. In contrast, that of metal heads was 2.43 um, and the profiles were in wide distortion compared with both alumina heads. The surface roughness was 0.012 um in the contact area, and 0.009 um in the non-contact area of retrieved SG-alumina heads. The surface roughness in the contact area, 0.007 um, of XSG-alumina was slightly higher than that in the non-contact area, 0.003 um, and the both area of XSG-alumina represent lower value than SG-alumina, with all alumina heads having a reentrant surface profile. In contrast, the surface roughness of metallic heads was in a range of 0.003–0.053 um and several heads showed the protrusion surface profile. In this retrieval study, the roundness and the roughness of both alumina ceramic femoral heads after long-term clinical use were low and stable compared with metallic heads. And also, the surface roughness increased in the order of XSG-alumina < SG-alumina < metallic head. The alumina ceramic femoral head showed the reentrant surface whereas the metallic head showed the protruding surface. When third-body wear occurs during the clinical use, generally reentrant form may occur on the ceramic surface whereas protrusion form may occur on the metallic surface. We have good clinical results more than 20 years using the SG-alumina, and clinical results for a long term will be expected with XSG-alumina of improved microstructure


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 98 - 99
1 Mar 2008
Dickey I Hugate R Reach J Zobitz M Zhang R G M
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Trabecular materials show great promise for soft-tissue attachment to prosthetic implants. Results with Tantalum have been very encouraging, however, it remains unclear if this in-growth is secondary to the specific metal or its generic structure,. If structure, is there a specific tolerance with respect to porosity and pore size? In a canine model, bulk blocks of porous alumina ceramic were shown to be completely ingrown by four weeks. The type material was not a factor, and effect of pore size revealed that there is a wide tolerance in facilitating in-growth with the larger pores having the greatest attachment strength (p=0.004). This study examines the in-vivo soft tissue in-growth potential of porous alumina ceramic and the effect of three distinct pore size ranges on this process. Alumina ceramic implants of fixed porosity (~ 85%) were designed in three pore size ranges (100–200, 250–400 and 600–800 μM). Using an established canine model, six implants (two of each type) were implanted in the dorsal subcutaneous tissues of tweleve mature canines and examined histologically and mechanically at four, eight and sixteen weeks with respect to type, amount and strength of soft tissue in-growth. Soft tissue in-growth was grossly evident in all implants at each time interval, and in each pore size. Microscopic examination revealed neo-vascularized in-growth throughout the implant, without evidence of inflammation or foreign body reaction. Numerous blood vessels were visible at the implant interface and within the porous alumina ceramic structure. With peel testing, the weakest attachment strength was with the small pore size with no differences between the medium and large pore sizes. An increase of attachment strength in each pore size was observed over time. This study suggests that architecture of porous structures in general, and not the type of material used, confers the biologic activity and that there is a wide tolerance for pore size in facilitating this process in soft tissue in-growth. Further study of other inert foam structures will be useful in further defining the assets and limitations of this genre of trabecular materials as a whole. Funding: Stryker Orthopaedics, Mahwah, NJ. Please contact author for figures, graphs, and/or diagrams


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 9 | Pages 1220 - 1221
1 Sep 2005
Wroblewski BM Siney PD Fleming PA

We report the results of our continued review of 11 total hip arthroplasties using 22.225 mm alumina ceramic femoral heads on a Charnley flanged stem, articulating with chemically cross-linked polyethylene. There was an initial bedding-in of up to 0.41 mm at the articular surface in the first two years. This had not progressed further, at a minimum follow-up of 15 years. Radiographically no femoral or acetabular component showed loosening or osteolysis


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 446 - 446
1 Nov 2011
Oonishi H Kim S Oonishi H Kyomoto M Iwamoto M Ueno M
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In total hip arthroplasty (THA), one of concerned issues is osteolysis due to wear debris of ultra-high molecular weight polyethylene (PE) which often leads to aseptic loosening. Reduction of PE wear debris is essential to prevent osteolysis, and different bearing combination as well as improvement of the bearing material itself have been attempted. Hence alumina ceramics was introduced for THA, aiming to reduce PE wear debris. Ceramic on PE couple showed good results in clinical wear compared with metal on PE couples. Highly cross-linked PE (HXLPE) with gamma-ray or electron-beam irradiation followed by thermal treatment has also demonstrated a remarkably low wear in the previous in vitro studies. In in vivo studies, the wear of HXLPE acetabular cups against alumina ceramic femoral head was evaluated to compare with that of conventional PE cups against alumina ceramic femoral head. The in vivo wear of 61 HXLPE cups (Aeonian; Kyocera Corp., Kyoto, Japan, currently Japan Medical Materials Corp., Osaka, Japan) against alumina ceramic femoral head of 28 mm in diameter with clinical use for 2.1–7.1 years (mean 5.6 years) and eight conventional PE cups against an alumina ceramic femoral head of 28 mm in diameter used for 18.7–23.3 years (mean 20.4 years) were examined by radiographic analysis with Vector Works 10.5. The in vivo wear of eight retrieved HXLPE cups with clinical use for 0.9–6.7 years (mean 2.9 years) and 14 retrieved conventional PE cups used for 16.0–28.0 years (mean 22.0 years) were examined by using a three-dimensional coordinate measuring machine. The worn surfaces of retrieved HXLPE and conventional PE cups were observed by a scanning electron microscope. In the radiographic study, penetration rate of alumina head into HXLPE and conventional PE for the first 1 year were 0.24 mm/year and 0.34 mm/year respectively. One year later, the HXLPE showed significant lower penetration rate of 0.001 mm/year than the conventional PE penetration rate of 0.12 mm/year (p< 0.01). By the retrieval analysis, the mean penetration of retrieved HXLPE and conventional PE cups were 0.11 and 2.97 mm, and they were similar to the results by radiographic analysis. In the worn surface of the retrieved HXLPE cups used for around 1 year, machine marks were observed. In contrast, the worn surface of the retrieved HXLPE cups used for more than five years were smooth, and furthermore, in high magnification observation they had wear morphology different from conventional PE. These findings from this retrieval study suggest the penetration in the first 1 year detected by radiographic measurement was probably caused by creep deformation in bedding-in stage; and 1 year after, the penetration was probably caused mainly by wear. By the radiographic analysis, HXLPE cups against alumina ceramic femoral head has a 99 % lower wear rate compared with conventional PE cups. Also, retrieved HXLPE cups against alumina ceramic femoral head exhibited lower wear compared with conventional PE cups. In conclusion, we expect that the HXLPE cup used with alumina ceramic femoral head has favorable wear properties in long-term clinical use


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_II | Pages 127 - 127
1 May 2011
Yeung E Bott PT Jackson M Walter W Walter W Zicat B
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Aim: Alumina ceramic on ceramic bearings have gained popularity in hip arthroplasty due to the properties of low wear, low friction and chemically inert wear debris. In a previous study, we reported the excellent clinical results of a series of cementless ceramic on ceramic primary total hip arthroplasties at a minimum of 5 years. We now present the follow up results at 10 years. Method: Between June 1997 and February 1999, 301 consecutive, primary cementless hip arthroplasties were performed on 283 patients in our unit. The mean age of the patients was 57.8 years, with 145 (51%) being female. All of the hips received the same implant: (Osteonic ABC cup and Secure-Fit or Secure-Fit Plus stem; Stryker Orthopaedics). A third generation alumina ceramic on ceramic bearing (Biolox Forte; CeramTec) was used for articulation in all cases. All the operations were performed through a posterior approach with enhanced posterior repair, and the post-operative protocols were the same for all the patients. The clinical and radiographic outcome at 10 years were analysed. Results: At 10 years, 7.3% had died of unrelated cause and 3% were revised. The average Harris Hip score was 94.3 points at the last follow up. Ninety six percent of patients scored an excellent or good result, with less than 3% have moderate residual pain. Radiographically, all patients assessed had evidence of stable bony ingrowth. There were nine revisions in all, four stem revisions due to periprosthetic fracture, one secondary to aseptic loosening and one to facilitate a femoral shortening osteotomy. There was one cup revision for psoas tendonitis and one for cup repositioning. This same patient subsequently underwent further revision due to acetabular osteolysis with metallosis and some ceramic wear. Overall, the survival rate of the implants was 96% at 10 years. The retrieved femoral heads showed a median wear rate of 0.2 cubic millimeters per year. Conclusions: Alumina ceramic on ceramic bearings in cementless primary total hip arthroplasty had been shown to have good survival rate at 10 years with good function, low wear rate and no adverse radiographic changes. The one case of osteolysis may be due to ceramic wear debris or may be due to metal wear debris from the neck to rim impingement


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 353 - 353
1 Sep 2005
Orec R Pitto R Schmidt R
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Introduction and Aims: Recently, concerns have emerged regarding the high stiffness of acetabular components inserted with alumina ceramic liners, which might potentially cause early migration and loosening. This study was designed to investigate in-vivo the migration pattern of these constructs. Method: Fifty patients (50 hips) operated on using the same surgical technique and the same prosthesis were randomised in two groups. The study group of hips was treated with an alumina ceramic liner, the control group of hips received a polyethylene liner. An alumina femoral head with a diameter of 28mm was used in all hips. Radiostereometric analysis (RSA) was performed to assess migration using serial follow-up radiographs. Results: The median pre-operative Harris hip score (HHS) was rated 48.9 points in the alumina group, and 47.7 points in the polyethylene group. At the two-year follow-up, the median HHS of the alumina group was rated 94.1 points, and was rated 93.7 points in the polyethylene group. There were no clinical or radiological signs of aseptic loosening. RSA of the alumina group of cups showed a median axial displacement of 0.026 mm (SD 0.35mm). The median axial displacement of the polyethylene group was 0.047 mm (SD 0.26 mm) (p=0.9). The median tilting of the cup was 0.21 degrees (SD 0.54 degrees) in the alumina group, and 0.35 degrees (SD 0.71 degrees) in the polyethylene group (p=0.12). Conclusion: At an average of two years post-operatively, the cups inserted with an alumina ceramic liner appeared stable, RSA showed low rates of non-progressive migration. Results did not differ from those observed using the same cup inserted with a polyethylene liner


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 473 - 473
1 Nov 2011
Bierbaum B Ward D Robbins C
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Wear simulator studies suggest low wear rates of Alumina ceramic femoral heads with polyethylene total hip bearings. Short-term wear and clinical data of ceramic/highly crosslinked ultra-high molecular weight polyethylene (UHMWPE) couples are under reported in the literature. A retrospective review was performed to determine and compare the wear rate for hips implanted with an Alumina ceramic femoral head and X3® poly-ethylene insert to the acceptable polyethylene wear rate in the literature. We evaluated 70 primary total hip replacements performed at one institution, by two surgeons, from February 2006 through June 2007. At a minimum 2 year follow-up, calculated annual wear for the ceramic/X3. ®. polyethylene articulations showed a significant decrease compared to literature reports of 0.1mm/year or greater for conventional polyethylene. Radiographic and clinical outcomes show no loose implants, dislocations, ceramic fractures or revision surgeries at last follow-up. These early findings suggest that ceramic/X3. ®. bearing couples may serve as an acceptable choice for the younger, active patient


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_12 | Pages 43 - 43
1 Nov 2015
Rajpura A Wroblewski B Siney P Board T Jones HW
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Introduction. Cross linked polyethylene (XLPE) has gained popularity as a bearing surface of choice for younger patients despite only medium term results being available for wear rates. Concern remains regarding the long-term stability and durability of these materials. In order to address these issues we present the longest radiological and clinical follow-up of XLPE. Patients/Materials & Methods. Since 1986, we have prospectively studied a group of 17 patients (19 hips) that underwent a cemented Charnley low friction arthroplasty using a combination of 22.225mm alumina ceramic femoral head, a modified Charnley flanged stem and a chemically cross-linked polyethylene cup. We now report the 28 year clinical and radiological results. Results. At the latest review nine patients (11 hips) were still attending for clinical and radiographic follow-up at a mean of 27.5 years (26 – 28). The mean age at surgery in this group was 47 years (26 – 58). Seven patients died whilst still under follow-up, and one was revised at 17 years for late deep infection following urological surgery. There have been no mechanical failures of the components and no aseptic loosening. The mean initial penetration rate at 1 year was 0.13mm/year; between one and four years was 0.034mm/year; and between 4 years and latest follow-up (mean 27.5 years) was 0.007mm/year. One patient in this group subsequently had a contralateral Charnley metal on UHMWPE hip replacement and had a total cup penetration of 6.1mm at 27 years, compared to 0.41mm at 28 years in the XLPE and alumina ceramic combination. Conclusion. The clinical and radiological results in this group of patients remain excellent with no aseptic loosening. There was an initial bedding in period, after which there was an extremely low wear rate. The results highlight the long term stability and durability of cross-linked polyethylene when used in combination with a small diameter alumina ceramic head


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 418 - 418
1 Nov 2011
Oonishi H Oonishi H Kim S Kyomoto M Iwamoto M Ueno M
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A consensus on total hip arthroplasty (THA) concluded that the major remaining issues of concern included the long-term fixation of the joint replacement, osteolysis due to poluethylene (PE) wear debris which often leads to aseptic loosening. Alumina ceramics had been extensively used in medicine, and we started using the alumina ceramic for THA bearing surface in hopes to reduce the PE debris. It was because alumina ceramics is advantageous for precision machining compared with metal materials, and its hardness is higher than that of metal materials. Also, to augment cement–bone bonding, we interposed hydroxyl apatite (HA) granules at the cement–bone interface, so called “Interface Bioactive Bone Cement (IBBC) technique”. HA granules (2–3 g) were smeared on the bone surface of the acetabulum and femur just before cementing. In this study, we evaluated 19–22 years clinical results of THA with alumina ceramic head combined with PE cup fixated IBBC technique. Total 285 joints (212 patients) were implanted by one senior surgeon from January 1986 to December 1988, and 265 joints (192 patients) were traceable. Alumina ceramic femoral head of 28 mm in diameter and acetabular cup of the conventional PE sterilized with ethylene oxide gas were used in all patients. The PE cup and stem were fixed with IBBC technique in all cases. The presence of radiolucent line, loosening and osteolysis were observed using radiograph of the traceable cases. The locations of radiolucent lines were identified according to the zones described by DeLee and Charnley for acetabular cups and the zones described by Gruen et al. for femoral stems. The in vivo wear of 21 PE acetabular cups for 19.0–21.9 years (mean 20.3 years) was measured from the latest radiographs using computer assistant technique with Vector Works 10.5 software. Features of the clinical radiograph images of the IBBC case were classified as follows: the radiolucent line represented “gap” between the HA layer and the cement; the loosening represented “opening” between the HA layer and the cement. For the quantitative analysis, we divided the surrounding bones of the THA into several zones as done in the previous studies. The “gap” appeared in zone 4 in three joints (1.4 %), in zone 3 in two joints (0.9 %) of acetabular cup. In femoral side, in zone 1 in four joints (1.8 %) in zone 7 in one joint (0.4 %). The “opening” appeared in three acetabular cup (1.4 %). Since no opening was appeared in zone 3 or zone 4, however, no re-operation was needed. Images of osteolysis were seen one in zone 1 (0.5 %), and one in zone 2 (0.5 %) in acetabular side and two in zone 1 (0.9 %) of the femur. The mean linear wear rate of PE acetabular cups was 0.13 mm/year. The fixation to the bone by the IBBC technique has been maintained for long term. We think that the result was brought by the biological integration between bone and HA granules. In conclusion, this study has shown satisfactory results of the cemented THA with ceramic head combined with PE cup for 19–22 years


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 393 - 393
1 Apr 2004
Newman MA
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The study was designed to compare the clinical performance of an Alumina ceramic acetabular bearing to that of a polyethylene bearing in a cementless hip couple. The study group consisted of 15 surgeons who performed 308 total hip replacements (297 patients) between January 29, 1998 and February 1, 2000. All patients received a porous coated cementless titanium stem with an Alumina ceramic 28 mm or 32 mm head. Patients were randomized to receive a porous titanium acetabular shell with either a polyethylene or Alumina cup liner. There were 164 Alumina cups and 144 polyethylene cups. The mean age was 57.3 years and consisted of 50% males and 50% females. The preoperative diagnoses were: osteoarthritis 69.8%, avascular necrosis 19.5 %, post traumatic arthritis 2.9 %, inflammatory arthritis 3.9% and other 3.9%. The mean follow up was 12 months. The longest follow up was 38 months. The Harris Hip Score was good and excellent in 86% of the control patients and 87% of the study patients. There has been 100% follow up and survivorship. There were two reoperations for recurrent dislocations in each group. There were no Alumina component fractures, no progressive radiolucencies and no evidence of rapid wear. In the short term follow-up between 12 and 38 months, there do not appear to be any differences between the patients with a bearing couple consisting of Alumina on plastic with those consisting of Alumina on Alumina. There have been no catastrophic failures of the ceramic components. The Alumina/Alumina bearing couple for total hip arthroplasty appears to be an excellent alternative bearing, providing the advantage of improved long term wear and a reduced incidence of polyethylene induced osteolysis


The Journal of Bone & Joint Surgery British Volume
Vol. 81-B, Issue 1 | Pages 54 - 55
1 Jan 1999
Wroblewski BM Siney PD Fleming PA

We report the results of our continued review of 14 hip arthroplasties using alumina ceramic femoral heads with cross-linked polyethylene cups. There have been no complications and a very low rate of penetration. This was 0.02 mm per year after an initial ‘bedding-in’ period of two years. There has been no change in the mean rate between our earlier study at six years and the current results at 10 to 11 years. The use of these bearing surfaces appears to reduce the potential amount of polyethylene debris and may provide the next logical stage in the development of the Charnley low-friction arthroplasty


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 438 - 438
1 Apr 2004
Sarin VK Stulberg SD Yasuda K
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A retrospective study was performed to evaluate the safety and effectiveness of an alumina-based total knee arthroplasty system (Low Friction Anatomical, LFA, Kyocera, Kyoto, Japan). The system, which uses modern materials and contemporary component design, has been in clinical use in Japan since 1992. The system uses an alumina femoral component that articulates against standard polyethylene tibial and patellar components. The retrospective study evaluated the clinical performance of amodern-style ceramic femoral component and included 60 knees (49 patients) with an average follow-up of 3.8 years. Clinical outcomes were assessed by the Japanese Orthopaedic Association (JOA) Knee Rating Scale, which is comparable to the Knee Society Rating Scale used in the United States. Radiographic outcomes were assessed by the operating surgeon and another independent reviewer. The radiographs were reviewed for the presence or absence of lytic lines, implant and anatomical alignment, and other pertinent radiographic findings. Complications during the follow-up period were noted. Total knee replacement with the LFA system improved JOA scores in 98% of the cases. Mechanical and prosthetic alignment were satisfactory for all knees. The following results were noted:. No fractures or failures associated with the alumina ceramic femoral component. No problems with subsidence or abnormal bone remodeling. Absence of lytic lines in 96% of cases. Absence of complication in 94% of cases. Overall success rate of 96% at an average follow-up of 3.8 years. An alumina-based total knee replacement system was found to be a safe and effective means of treating the arthritic knee joint. The use of ceramics in total knee arthroplasty applications provides an opportunity for a low friction bearing interface and a completely metal-free total joint system


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 419 - 419
1 Apr 2004
Kawanabe K Tamura J Nakamura N
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We have been using a Charnley type hip prosthesis with an alumina ceramic head. Three sizes of alumina head, 28, 26 and 22mm, were employed and the Ortron 90 Charnley total hip prosthesis was used at the same period. The objective of this study was to compare the survival rate and the wear rate of those four groups. There were 90, 62, 322 and 88 hips in 28, 26, 22mm alumina head and 0rtron 90 head group. Average age at operation was 49.5, 57.8, 58.0 and 60.6, respectively. A 28 mm prosthesis was indicated for relatively young patients. The mean duration of follow-up was 156, 97, 49 and 110 months, respectively. Twenty patients were chosen at random for each of four groups and the linear wear as seen on X-ray film was measured every two years with a computer and scanner. Results: The average linear wear rate (mm/yr) was 0.179 for the 28mm, 0.112 for the 26mm, 0.115 for the 22mm alumina head and 0.075 for the Ortron 90 head. The difference between the 28mm group and the other three groups was analyzed statistically. The Kaplan-Meier survivorship analysis, with revision for aseptic loosening as the endpoint, showed the survival rate of the 28mm group appeared to be inferior to that of the other three groups. Discussion: Our study showed that the wear rate of the 28mm alumina group was highest because low grade alumina was used. In addition, the polyethylene socket used for the 28mm group was thinner than that for the other groups. No clinical superiority of ceramics to metal in terms of polyethylene wear can be shown in this study. A randomized prospective study should be carried out to determine whether an alumina ceramic head is clinically superior to a metallic head in terms of polyethylene wear


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXI | Pages 114 - 114
1 May 2012
B. MW P. S P. F
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Introduction. Wear of the ultra high molecular weight polyethylene (UHMWPE) cup and the resulting loosening has been shown to limit the long-term results of the Charnley low-frictional torque arthroplasty (LFA). Factors affecting wear rates have been studied: level of patient activity, effective roughness of the stainless steel head, impingement and the possible variations in wear characteristics of UHMWPE. Since patients' activity level cannot be predicted or modified, alternative materials were examined. Methods and Results. The Charnley 22.225 mm diameter head of alumina ceramic in combination with chemically cross-linked polyethylene cup has now reached over 23 years of clinical and radiographic follow-up. Of the initial 17 patients (19 hips) in the study, 4 patients (4 hips) have died, 1 hip has been revised for deep infection and 3 patients (3 hips) are unable to attend follow-up due to medical problems unrelated to the hip. Nine patients (11 hips) are still attending follow-up at a mean of 22 years 5 months (21 year 3 months-23 years 6 months). The mean age at surgery in this group was 47 years (26-58) and the mean weight 81kgs (54-102). The mean penetration rate was 0.02mm/year and none have exceeded 0.41mm total penetration. Conclusion. Since the problem of cup wear and loosening is mechanical rather than biological the long-term solutions are more likely to come from materials rather than radical changes of design of methods of component fixation


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 168 - 169
1 Mar 2010
Ecker T Robbins C van Flandern G Patch D Steppacher S Bierbaum B Murphy S
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Alumina ceramic-ceramic bearings have the benefit of very low wear and studies showing the complete absence of osteolysis during the first decade of close study. However, good results depend on several critical factors including surgical exposure, surgical technique, component placement, and choice of component design. The following abstract discusses our experience with several of these factors. Initially, there were concerns that the use of ceramic-ceramic bearings would lead to a higher incidence of hip dislocation since the bearings have fewer femoral head-length choices and the absence of lipped-liners. In our prospective study of 418 hips the incidence of hip dislocation at 1 to 10 year followup is 0.5% (2/418). This experience suggests that the use of alumina ceramic-ceramic bearings is not associated with an increased incidence of dislocation. More recently, concerns about squeaking of alumina ceramic-ceramic bearings have been reported, particularly from centers in the United States. To investigate this issue, we reviewed information on 1275 consecutive revision THAs and 1039 consecutive primary ceramic-ceramic THA that had been performed at two institutions between 1996 and 2007. To identify the influence of the implant design on the incidence of squeaking we divided the primary hips into three groups with group 1: flush mounted ceramic liner; group 2a: recessed ceramic liner mated with a stem made of TiAlV; and group 2b: recessed ceramic liner mated with a stem made of a beta titanium alloy comprised of 12% molybdenum, 6% Zirconium, and 2% Iron. Analysis of the 1275 revision hips revealed 5 alumina ceramic-ceramic hips in patients who complained of squeaking or grinding. All 5 hips were designs that included a ceramic liner that was recessed inside of an elevated metal rim. All 5 hips also demonstrated metallosis at the time of revision. In primary THA, Group 2b had statistically significantly more squeaking (9 of 118) than group 2a (10 of 321) which had statistically significantly more squeaking than group 1 (6 of 700). In addition, the severity of squeaking between the groups was qualitatively different. Patients in Group 2b who complained of squeaking would often experience squeaking frequently throughout the day and could be demonstrated in the physician’s office. By contrast, patients in Group 1 who noted squeaking stated that the hip squeaked once a day to once a year. No patient in Group 1 complained of frequent squeaking or could demonstrate squeaking in the physicians’ office. Further, joint fluid analysis from a patient in Group 2b who complained of squeaking revealed metal from both the femoral (Molybdenum) and acetabular (Aluminum) components. As reported in another abstract at this meeting, 10 year survivorship of flush-mounted alumina ceramic-ceramic THA is 98.4% (95% confidence interval 97.1–100%) and no patient in that prospective clinical studies demonstrated radiographic evidence of osteolysis or wear. These experiences demonstrate that THA using alumina ceramic-ceramic is extremely reliable with low revision and dislocation rates and an absence of osteolysis. Significant squeaking is not associated with flush-mounted alumina ceramic liners and is clearly associated with elevated metal rims and metallosis. Finally, squeaking is statistically significantly associated with femoral components made of a beta titanium alloy consisting of Titanium, Molybdenum, Aluminum, and Iron


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_II | Pages 234 - 234
1 May 2006
Wroblewski PB Siney P Fleming P
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We report the results of our continued review of 11 hip arthroplasties using 22.225mm alumina ceramic femoral heads (CCH) on a Charnley flanged stem articulating with a chemically cross-linked polyethylene (XLPE) cup. The initial bedding-in of up to 0.41mm, which was reached within about 2 years, has not progressed further with a follow up to 18.1 years. The mean total penetration of the XLPE cup for this group of patients is 0.31mm (0 – 0.41) and a penetration rate of 0.019 mm/year (mean 0 – 0.026). One patient with CCH/XLPE arthroplasty on the left side and a conventional metal on ultra high molecular weight polyethylene (UHMWPE) on the right side, has a ten fold difference in total penetration: 0.41mm compared with 4.1mm and a year shorter follow-up. The mean age of the 9 patients (11 hips) attending was 47.2 years (26–58) at the operation and is now 64 years (42–73). Clinical results remain excellent with freedom from pain and normal activity level appropriate to their age and gender. Radiographically none of the cups or stems show evidence of loosening or osteolysis and there have been no problems that could have been attributed to the materials or the design used


Hypersensitivity to metal alloy orthopaedic implants has become identified increasingly as a cause of implant failure. Because of their hypoallergenic properties, ceramic materials have been recommended as an alternative to metals. Unfortunately, the cost of ceramics and limitations imposed by their material properties has restricted these applications. The metalloceramic composite Oxinium® has been suggested as asubstitute. This is the first study to prospectively compare these materials in patients with documented cobalt-chrome hypersensitivity. Over a period of ten years, preoperative screening using skin patch testing and in vitro leukocyte stimulation testing of patients with gonarthrosis and a history of metal hypersensitivity identified sixteen patients with allergy to cobalt-chrome alloy. Twelve (all& ) underwent primary, and four underwent revision (3& , 1%) knee replacement surgery using either alumina ceramic femoral components (3 primary, 2 revisions) or Oxinium® femoral components (9 primary, 2 revisions) All implants were fixed with acrylic cement, and all-polyethylenetibial implants were used in each procedure. None of the patients in the primary groups developed symptoms of allergic reaction at a minimum of one year following surgery. Serial serum antibody and leukocyte stimulation studies have shown no reaction following placement of either type of prosthetic knee. Those undergoing revision surgeries had rapid resolution of preoperative symptoms of pain, effusion and eczematous rash. Serum studies showed a concomitant fall inantibody levels. The two patients undergoing revision surgery with alumina femoral implants subsequently underwent second revisions (both at 8 years) using Oxinium® femoral implants. Neither developed clinical symptoms orchanges in antibody profile. While the number of patients in the present study is relatively small, it is the only independent, prospective, clinical comparison of these materials. The uniformly good results suggest implants of Oxinium® offer the hypoallergenic properties of alumina without adverse-material properties and at a lower cost


Orthopaedic Proceedings
Vol. 85-B, Issue SUPP_I | Pages 20 - 20
1 Jan 2003
Wroblewski B Siney PD Fleming PA
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Ultra high molecular weight polyethylene (UHMWPE) was introduced into clinical practice by Charnley in November 1962 and has remained the standard material for the hip and other total joint arthroplasties. Wear of the UHMWPE cup, although studied from the beginning, did not appear to be a clinical problem although Charnley suspected that this would be so in the long term. A review of the outcome of the Charnley low-friction arthroplasty in patients under the age of 40 years at the time of the operation has shown that the incidence of cup migration was exponentially related to the depth of cup penetration. A prospective study using 22.225 mm alumina ceramic (Al 20 3 ) head articulating with cross linked polyethylene was set up with the initial penetration of 0.2 – 0.4 mm in about 2.5 years with no further penetration. The clinical results mirrored closely the experimental results obtained with the identical set of materials and design. The clinical results have now reached 14 year follow-up and the initial total penetration of 0.2 – 0.4mm has remained unchanged. Review of long term results of the Charnley LFA has shown a mean penetration rate of 0.1 mm/year (0.02 – 0.6). With a mean penetration rate of 0.1 mm/year, the revision rate for cup wear and loosening in patients under the age of 50 at the time of the LFA, and with a follow-up to 32 years, is in the region of 10%. If the penetration rate remained at 0.02 mm/year or less then no cups have been revised for aseptic loosening. Ceramic / UHMWPE articulation is the next stage of evolution of the Charnley LFA. A prospective study using zirconia 22.225 mm head is approaching 7 year follow-up in over 1000 cases


Orthopaedic Proceedings
Vol. 85-B, Issue SUPP_I | Pages 74 - 74
1 Jan 2003
H I K N S M M K
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Introduction. Total elbow arthroplasty (TEA) is a widely accepted for the treatment for damaged rheumatoid elbows to achieve sufficient joint function. The current prospective study reports the long term follow-up of TEA with an unlinked stem type (Stemmed Kyocera type I, SKC-I) with a solid trochlea on patients who have rheumatoid arthritis (RA). SKC-1 is derived from an unlinked surface replacement prosthesis using polycrystalline alumina ceramics on high-density polyethylene (Kyocera type I), which was developed in 1979, based on the measurement study on the cadaveric elbows. Materials and Methods. 57 elbows (Larsen’s grade IV and V) from 45 RA patients replaced by SKC-1 were investigated. Cement fixation was used in all cases. The duration of follow-up ranged from 36 to 154 (average 73. 7) months. The clinical condition of each elbow before and after operation was assessed according to the scoring system of Japanese Orthopaedic Association (JOA) elbow scoring system (maximum 100 points), which is composed of scores for pain, activity of daily life, muscle strength, range of motion, instability, and deformity of the joint. On the basis of this system, the results are defined as excellent (90–100 points), good (75–89), fair (60–74), and poor (< 60). Radiographic loosening was defined as a progressive radiolucent line of more than two millimeters that completely surrounded the prosthesis. Results. The average postoperative JOA score improved from 43. 5±10. 2. °. to 81. 0±}10. 3. °. , with marked pain relief. The mean range of motion (ROM) of extension/flexion before the surgery was –35. 7±}22. 4/117. 1±}19. 1. °. and at last follow-up was −17 5±}12. 7/136. 3±}11. 4. °. The mean ROM of pronation /supination improved from 51. 1±}23. 4/56. 5±}28. 5. °. to 78. 3±}16. 8/82. 3±}16. 5. °. Of the 57 elbows, 9 elbows were judged to have excellent results, 37 had good results, 8 had fair results, and 3 had poor results. There were no instances of ulnar nerve palsy, triceps avulsion, or postoperative infection. Medial or lateral epicondylar fracture occurred in 2 cases during the operation, and union was achieved 3 months later. Massive instability with joint dislocation was seen in 3 cases of mutilans arthritis, resulting in poor results. Aseptic loosening was seen in 3 elbows. Revision surgery was performed in 1 case of accidental post-operative distal humerus fracture, and in another of olecranon fracture with the breakage of the ulnar component. With loosening defined as the end point, Kaplan-Meier curve of the cumulative probability of survivorship demonstrates the likelihood of survival of the prosthesis at 93. 8 percent for as long as 10 years. Discussion. The results of the current study showed a high reliability of the SKC-1 prosthesis with the novel alumina ceramic component over a long period when implanted with cement. However, the use of non-constrained devices is limited by the amount of bone and by the need for ligamentous stability. If soft tissues are damaged along with marked bone loss or inflammatory changes, the ligament should be repaired or a semiconstrained type of prosthesis is indicated. It is important to note that a high level of surgical technique is required for TEA in RA elbows to avoid typical postoperative complications


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_14 | Pages 71 - 71
1 Dec 2019
Denes E Fiorenza F Toullec E Bertin F Balkhi SE
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Aim

Local concentration of antibiotic at the site of infection is a major parameter for its efficiency. However, bone diffusion is poor leading either to their non-use (ex: gentamicin) or the use of high concentration (ex: vancomycin). Local administration could optimize their local concentration combined with lower side effects. We report the clinical experience and pharmacological results of an antibiotic loaded porous alumina used to replace infected bone in 4 patients.

Method

Two patients had a destroyed sternum following mediastinitis; one presented a femoral chronic osteomyelitis due to MRSA and one had an infected ankle arthroplasty. The ceramic was loaded with gentamicin in three cases and vancomycin for the ankle infection. Local dosages thanks to Redon's drain and blood samples were performed. Loading was done to protect the device while implanted in an infected area and was combined with conventional antibiotic therapy.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_5 | Pages 129 - 129
1 Mar 2017
Lim S Ryu H Yeo I Lee W Park C Kim K Kim S Park Y
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Purpose

The fourth generation ceramic, in which zirconia is incorporated into the alumina matrix, was developed to reduce the risk of ceramic fractures. The purpose of this study was to evaluate the survivorship, clinical and radiographic results, and bearing-related failures associated with total hip arthroplasty using zirconia-toughened alumina ceramic-on-ceramic bearings over a minimum follow-up of 5 years.

Materials and methods

We retrospectively analysed 135 patients (151 hips) who underwent cementless total hip arthroplasty using zirconia-toughened alumina ceramic-on-ceramic bearings. There were 58 men and 77 women with mean age of 55.9 years (range, 20 to 82 years) at index surgery. Acetabular and femoral components were cementless in all hips. A 36 mm head was used in 81 of 151 hips and a 32 mm head was used in 70 hips with smaller acetabular shells. The mean duration of follow-up was 6.1 years (range, 5 to 6.8 years).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_7 | Pages 34 - 34
1 May 2016
Beckmann N Gotterbarm T Innmann M Merle C Kretzer J Streit M
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Introduction

The optimal bearing for hip arthroplasty is still a matter of debate. in younger and more active patients ceramic-on-polyethylene (CoP) bearings are frequently chosen over metal-on-polyethylene (MoP) bearings to reduce wear and increase biocompatibility. However, the fracture risk of ceramic heads is higher than that of metal heads. This can cause serious issue, as ceramic fractures pose a serious complication often necessitating major revision surgery – a complication more frequently seen in ceramic-on-ceramic bearings. To date, there are no long-term data (> 20 years of follow-up) reporting fracture rates of the ceramic femoral heads in CoP bearings.

Patients and Methods

We retrospectively evaluated the clinical and radiographic results of 348 cementless THAs treated with 2nd generation Biolox® Al2O3 Ceramic-on-Polyethylene (CoP) bearings, which had been consecutively implanted between January 1985 and December 1989. At implantation the mean patient age was 57 years. The cohort was subsequently followed for a minimum of 20 years. At the final follow-up 111 patients had died, and 5 were lost to follow-up (Fig. 1). A Kaplan-Meier survivorship analysis was used to estimate the cumulative incidence of ceramic head fractures over the long-term.


The Journal of Bone & Joint Surgery British Volume
Vol. 77-B, Issue 4 | Pages 548 - 556
1 Jul 1995
Sugano N Nishii T Nakata K Masuhara K Takaoka K

From 1981 to 1983, we implanted Bioceram type-4 and type-5 prostheses in 61 hips in 54 patients with osteoarthritis secondary to acetabular dysplasia, congenital subluxation, or congenital dislocation of the hip. Fifty-seven hips in 50 patients were followed for a mean of 11.1 years (10 to 13). The mean age of the patients at operation was 53 years (31 to 70). Functional evaluation using the Merle d'Aubigne and Postel hip score showed a 77% success rate. Radiological loosening occurred in three femoral (5%) and 16 acetabular components (28%). Autologous femoral head grafts were used in 18 hips and became incorporated, giving mechanical support to the socket except for one which occupied a large weight-bearing area and eventually collapsed. The mean polyethylene wear was 1.1 mm (0 to 3.6) and the mean wear rate was 0.10 mm/year (0 to 0.31). A high rate of wear correlated with calcar resorption (p > 0.002) but not with acetabular loosening. There was no breakage of a ceramic head. Study of the ceramic heads and polyethylene sockets retrieved after ten years showed excellent surface roughness, sphericity, and bending strength for the heads but scratches and voids were seen on the sockets.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_3 | Pages 69 - 69
1 Jan 2016
Murphy S Le D Murphy W
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INTRODUCTION

Young patients (< 50 years old) have been reported to have a higher risk of revision following total hip arthroplasty (THA) than older patient cohorts, possibly to due higher activity, a higher incidence of deformity and greater probability of prior surgery. Ceramic-on-ceramic bearing surfaces have been proposed for use in young and active individuals due to their low wear, low risk of adverse biologic reaction, and long-term survivorship. We assessed the clinical results and long-term survivorship of uncemented ceramic-on-ceramic THA in a young patient population.

METHODS

Between August 1999 and December 2007, 220 total hip arthroplasties in 191 patients under 50 years of age at the time of surgery were performed using alumina ceramic-ceramic bearings as part of a prospective, non-randomized study. All patients received uncemented acetabular components with flush-mounted acetabular liners using an 18 degree taper, and uncemented femoral components. The average patient age at the time of surgery was 42.1 ±7.2 years (range: 17.4 years to 49.9 years), and the average time to follow-up was 10.1 ±2.4 years (range: 4.2 years to 15.2 years). We evaluated implant-related complications and performed Kaplan-Meier analyses to determine survivorship of the THA components with revision for any reason as the endpoint.


The Journal of Bone & Joint Surgery British Volume
Vol. 78-B, Issue 2 | Pages 280 - 285
1 Mar 1996
Wroblewski BM Siney PD Dowson D Collins SN

We report the findings from independent prospective clinical and laboratory-based joint-simulator studies of the performance of ceramic femoral heads of 22.225 mm diameter in cross-linked polyethylene (XLP) acetabular cups. We found remarkable qualitative and quantitative agreement between the clinical and simulator results for the wear characteristics with time, and confirmed that ceramic femoral heads penetrate the XLP cups at only about half the rate of otherwise comparable metal heads.

In the clinical study, 19 hips in 17 patients were followed for an average of 77 months. In the hip-joint simulator a similar prosthesis was tested for 7.3 million cycles.

Both clinical and simulator results showed relatively high rates of penetration over the first 18 months or 1.5 million cycles, followed by a very much lower wear thereafter. Once an initial bedding-in of 0.2 mm to 0.4 mm had taken place the subsequent rates of penetration were very small. The initial clinical wear during bedding-in averaged 0.29 mm/year; subsequent progression was an order of magnitude lower at about 0.022 mm/year, lower than the 0.07 mm/year in metal-to-UHMWP Charnley LFAs.

Our results show the excellent tribological features of alumina-ceramic-to-XLP implants, and also confirm the value of well-designed joint simulators for the evaluation of total joint replacements.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 273 - 273
1 Mar 2013
Steppacher S Tannast M Murphy S
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Young patients have been reported to have a higher risk of revision following total hip arthroplasty than older cohorts. This was attributed to the higher activity level which led to increased wear, osteolysis, and component fracture. We prospectively assessed the clinical results, wear and osteolysis, the incidence of squeaking, and the survivorship of ceramic on ceramic THA in patients younger than 50 years (mean age of 42 [18–50] years). The series included 425 THAs in 370 patients with 368 hips followed for a minimum of 2 years (mean 7.1 years, range 2–14 years). All patients received uncemented acetabular components with flush-mounted acetabular liners using an 18 degree taper. No osteolysis was observed in any uncemented construct. There was osteolysis around one loose cemented femoral component. The survivorship for reoperation for implant revision was 96.7%. There were only two acetabular liner fractures (0.47%) and one femoral head fracture (0.24%). Two of the three fractures involved a fall from a significant height. There were no hip dislocations. Five patients (1.17%) noted rare or occasional squeaking. None had reproducible squeaking. In summary, the current study shows that ceramic-on-ceramic THAs in the young patient population are extremely reliable with a very low revision rate and an absence of wear-induced osteolysis. In addition, it shows that both bearing fracture in this young patient population typically occurs with polytrauma and squeaking issues that have been raised relative to ceramic bearings occur very rarely with the flush-mounted ceramic liner design used in this study.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_II | Pages 214 - 214
1 May 2006
Nishida KK Fujiwara KK Hashizume KK Nasu YY Kitamura AA Inoue HH
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Objective: To investigate the long-term follow-up results of total elbow arthroplasty (TEA) with a non-constrained elbow prosthesis with a solid ceramic trochlea (Stemmed Kyocera type I, SKC-I) on patients who have rheumatoid arthritis (RA).

Materials and Methods: Between May 1988 and February 1999, 84 patients of RA underwent TEA with cement fixation (108 elbows). Fourteen patients (14 elbows) were lost due to change of address. One patient (1 elbow) required revision surgery due to aseptic loosening, and 2 elbow implants in 2 individuals were removed due to deep infection, and 18 patients (24 elbows) have died within 5 years after the surgery due to causes unrelated to TEA. Of the remaining 52 patients (70 elbows), 38 patients (53 elbows, 75.7%) were available for the over-5-year detailed clinical and radiographic review at a mean period of 9.2 years (range, 5–17 years). The clinical condition of each elbow before and after operation was assessed according to the Japanese Orthopaedic Association (JOA) elbow scoring system (up to 100 points).

Results: The average postoperative JOA score improved from 45.1 to 83.3 points with marked pain relief in all but 2 cases. The mean range of motion (ROM) of extension / flexion before the surgery was −35.6 / 117.1 and at last follow-up was −17.6 / 136.9 degrees. The mean ROM of pronation / supination improved from 49.6 / 55.8 to 80.0 / 82.1 degrees. Revision surgery was required in 2 patients (2 elbows) due to humeral fracture and ulnar component fracture, respectively. One elbow implant was removed due to deep infection. An ulnar component was removed from one patient with olecranon fracture. During the follow-up, 3 elbow joints had dislocated in 3 patients, and loosening was seen in 5 elbows in 5 patients. Of the 53 elbows, 45 elbows (84.9 %) were judged to have excellent (90–100) or good (75–89) results, and 2 elbows to have poor (< 60) results (0.04%). With loosening and revision or removal of the implant defined as the end point, the likelihood of survival of the prosthesis was 92.2 and 88.3%, respectively, for as long as 10 years by Kaplan-Meier analysis.

Conclusion: The results of the current study showed a high reliability over a long period of the SKC-I when implanted with cement. However, good results in the use of non-constrained devices are limited by the amount of bone and by the need for the ligamentous stability, which can be problematic in RA cases.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 198 - 198
1 Dec 2013
Imbuldeniya A Chana R Walter W Zicat B Walter W
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Introduction. The success of total hip arthroplasty has meant its indications have been extended to the younger more active patient. Due to the higher activity levels and increased demands of these patients, revision rates have been traditionally higher than when compared to older patients [1]. Ceramic on ceramic bearings may offer a viable long term solution as manufacturing methods have evolved resulting in improved mechanical properties, particularly of third and fourth generation ceramics. We report the outcome of primary cementless, alumina-on-alumina hip arthroplasty with a minimum 10 year follow up in 110 patients under the age of 55 years of age at time of surgery. Methods. A series of 120 consecutive total hip arthroplasties in 110 patients were performed between June 1997 and February 1999 by the two senior authors. All patients had an Osteonics ABC acetabular component and SecurFit or SecurFit Plus femoral component (Stryker Orthopaedics, Mahwah, NJ) with an alumina C-taper ceramic head (Biolox Forte, Ceramtec, Plochingen, Germany). Results. Of the 110 patients originally in the study, 4 (3.6%) patients died, 6 (5%) were lost to follow up and 4 hips (3.6%) were revised by the time of the latest follow up. Clinical information was available for 106 hips in 96 surviving patients at a minimum of ten years of follow-up, and radiographic information was available for 90 hips from the same 96 patients. The mean follow up was 11.5 years (range 10 to 13.5 years). Survivorship analysis with revision for any reason as an endpoint was 96.5% at 10 years (CI 94.5% −98.7%) using the Kaplan-Meier method. Modified mean UCLA scores improved from 6.4 (range 4 to 10) pre operatively to 9 (range 4 to 10) at latest follow up. The mean Harris Hip Score improved from 53.4 points (range 15 to 86) preoperatively, to 94.7 points (range 63 to 100) at latest follow up. All femoral stems had stable bone ingrowth, with no migration. Osteolysis was not observed around the femoral or acetabular components and there were no signs of radiological wear. 98 patients (92.4%) managed to continue with their current occupations during the follow up period whilst 5 patients (4.7%) changed occupation to work that required increased activity. Complications included 3 cases of iliopsoas tendonitis, 2 cases of squeaking, a ceramic liner chipping during insertion and sciatic nerve palsy. There were no cases of ceramic fracture in this younger, active cohort of patients. No evidence of bearing failure was demonstrated nor any signs of adverse reaction to wear debris. Conclusions. Alumina ceramic on ceramic bearings in cementless primary total hip arthroplasty show good clinical and radiological outcomes in the higher demand younger age patient. Based on these results we now support heavy occupational work and regular impact sports in these patients once they have recovered from surgery


The Bone & Joint Journal
Vol. 100-B, Issue 8 | Pages 1066 - 1073
1 Aug 2018
Nishida K Hashizume K Nasu Y Ozawa M Fujiwara K Inoue H Ozaki T

Aims

The aim of this study was to report the mid-term clinical outcome of cemented unlinked J-alumina ceramic elbow (JACE) arthroplasties when used in patients with rheumatoid arthritis (RA).

Patients and Methods

We retrospectively reviewed 87 elbows, in 75 patients with RA, which was replaced using a cemented JACE total elbow arthroplasty (TEA) between August 2003 and December 2012, with a follow-up of 96%. There were 72 women and three men, with a mean age of 62 years (35 to 79). The mean follow-up was nine years (2 to 14). The clinical condition of each elbow before and after surgery was assessed using the Mayo Elbow Performance Index (MEPI, 0 to 100 points). Radiographic loosening was defined as a progressive radiolucent line of >1 mm that was completely circumferential around the prosthesis.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 180 - 180
1 Mar 2008
Piconi C Maccauro G Muratori F Gasparini G
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The choice to use alumina in the manufacture of a low-wear THR bearing made by Boutin and its co-workers has proven its effectiveness in almost 35 years of clinical use. A continuous development process aimed to improve mechanical properties led to today’s materials that exhibit extreme high reliability.

The recent introduction in clinical use of alumina matrix composites represents the latest evolution of alumina that thanks to high hardness, toughness, and bending strength allow to manufacture new design of ceramic components. Composites obtained introducing zirconia in the alumina matrix, known as Zirconia Toughened Alumina (ZTA) are candidate for use in THA bearings from a long time. A real breakthrough was represented by alumina ceramics toughened both by zirconia both by platelets nucleated in-situ during sintering (Zirconia-Platelet Toughened Alumina - ZPTA).

The chemical composition and the microstructure of ZPTA were optimised to achieve a ceramic material joining strength of more than 1200MPa, Vickers hardness 1975, fracture toughness of 6,5 MPa m-1/2, andextremely low wear also in the most severe simulator tests performed in microseparation mode The paper reviews the improvements introduced in the technology of ceramic for arthoplasty, and their effects on the microstructural properties and on the performances of the past and actual generation of ceramic for THR bearings, and summarise the results obtained in the development of alumina matrix composites.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 176 - 176
1 Mar 2008
Patricie M
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The choice to use alumina in the manufacture of a low-wear THR bearing made by Boutin and its co-workers has proven its effectiveness in almost 35 years of clinical use. A continuous development process aimed to improve mechanical properties led to today’s materials that exhibit extreme high reliability. The recent introduction in clinical use of an alumina matrix composite developed by CeramTec and available under the trade name Biolox®Delta represents the latest evolution of alumina. This material allow new design in ceramic components thanks to its equilibrium among high hardness, high toughness, and high bending strength.

Composites obtained introducing zirconia in the alumina matrix, known as Zirconia Toughened Alumina (ZTA) are candidate for use in THA bearings from a long time. A real breakthrough was represented by alumina ceramics toughened both by phase transformation both by platelets nucleated in-situ during sintering. Optimised processing and quality control led to optimised material behaviour.

The chemical composition and the microstructure of Biolox®Delta were optimised to achieve a ceramic material joining strength of more than 1200 MPa, Vickers hardness 1975, fracture toughness of 6,5 MPam-1/2, and extremely low wear also in the most severe simulator tests performed in microseparation mode.

The paper reviews the improvements introduced in the technology of ceramic for arthoplasty, and their effects on the microstructural properties and on the performances of the past and actual generation of ceramic for THR bearings, and summarise the results obtained in the development of alumina matrix composite Biolox® Delta.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 11 | Pages 1529 - 1533
1 Nov 2012
Taniguchi A Takakura Y Sugimoto K Hayashi K Ouchi K Kumai T Tanaka Y

The purpose of this study was to evaluate the clinical results of a newly designed prosthesis to replace the body of the talus in patients with aseptic necrosis. Between 1999 and 2006, 22 tali in 22 patients were replaced with a ceramic prosthesis. A total of eight patients were treated with the first-generation prosthesis, incorporating a peg to fix into the retained neck and head of the talus, and the remaining 14 were treated with the second-generation prosthesis, which does not have the peg. The clinical results were assessed by the American Orthopaedic Foot and Ankle Society ankle/hindfoot scale.

The mean follow-up was 98 months (18 to 174). The clinical results of the first-generation prostheses were excellent in three patients, good in one, fair in three and poor in one. There were, however, radiological signs of loosening, prompting a change in design. The clinical results of the second-generation prostheses were excellent in three patients, good in five, fair in four and poor in two, with more favourable radiological appearances. Revision was required using a total talar implant in four patients, two in each group.

Although the second-generation prosthesis produced better results, we cannot recommend the use of a talar body prosthesis. We now recommend the use of a total talar implant in these patients.


The Bone & Joint Journal
Vol. 99-B, Issue 10 | Pages 1286 - 1289
1 Oct 2017
Rajpura A Board TN Siney PD Wynn Jones H Williams S Dabbs L Wroblewski BM

Aims. Our aim in this study was to describe a continuing review of 11 total hip arthroplasties using 22.225 mm Alumina ceramic femoral heads on a Charnley flanged femoral component, articulating against a silane crosslinked polyethylene. Patients and Methods. Nine patients (11 THAs) were reviewed at a mean of 27.5 years (26 to 28) post-operatively. Outcome was assessed using the d’Aubigne and Postel, and Charnley scores and penetration was recorded on radiographs. In addition, the oxidation of a 29-year-old shelf-aged acetabular component was analysed. Results. The mean clinical outcome scores remained excellent at final follow-up. The mean total penetration remained 0.41 mm (0.40 to 0.41). There was no radiographic evidence of acetabular or femoral loosening or osteolysis. There was negligible oxidation in the shelf-aged sample despite gamma irradiation and storage in air. Conclusion. These results highlight the long-term stability and durability of this type of crosslinked, antioxidant containing polyethylene when used in combination with a small diameter alumina ceramic femoral head. Cite this article: Bone Joint J 2017;99-B:1286–9


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 404 - 404
1 Nov 2011
Capello W
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At ten years, alumina ceramic bearings are functioning well with low complication rates and a fewer number of revisions than the control cohort. Alumina ceramic bearings have proven superior wear resistance, lubrication, and scratch resistance, without carrying the risk of metal ion release. In 1996 a U.S. IDE clinical trial was initiated utilizing newly improved alumina ceramic materials and implant design. The purpose of this multi-center, prospective, randomized study is to prove comparable safety and efficacy of alumina-alumina ceramic to a control cobalt chrome-polyethylene bearing. Four hundred fifty two patients (475 hips) are followed in this study. Subjects include ceramic on ceramic, with either porous coated cup or arc deposited cup, or control group with metal on polyethylene with porous coated cup. Average age of subject at time of surgery was 53 years with 82% diagnosis of OA. The average Harris Hip Score was 96 and 94% of hips had little to no pain. Kaplan-Maier survivorship at 10 years, component revision for any reason, was 95.9% for ceramic bearings compared to 91.3% for metal on polyethylene control. There have been nine hips requiring revision of one or both components for any reason. Data was recently collected on the subjects that participated in either the IDE or Continued Access arms of the ABC. ®. and Trident. ®. study. Data collection included revisions, complications, and noise. Out of 930 hips (848 patients) there were nine incidences of squeaking noise reported, no wear/osteolysis issues, and only two insert fractures (0.2%). At ten years ceramic bearings show no wear, inconsequential lysis, minimal breakage, and occasion noise. Clinically, alumina ceramic bearings perform as well as the metal-on-polyethylene, with fewer revisions and less osteolysis, suggesting that they are a safe, viable option for younger, more active patients


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_III | Pages 361 - 361
1 Mar 2004
DñAntonio JA Capello WN Manley MT Bierbaum B
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Aims: Todayñs major challenge for total hip arthroplasty is to minimize wear and osteolysis in our younger and more active patients. Alumina ceramic bearings have known superior wear resistance and lubrication and do not carry a risk of ion release. One objective of this clinical study was to evaluate the use of alumina-on-alumina ceramics with proven implants that have had successful track records with regard to þxation (on a prospective randomized basis)Methods: Utilizing new improved alumina ceramic materials and implant design 514 hips were implanted in a multicenter US IDE prospective and randomized study. The study compared alumina-on-alumina ceramic bearings to a cobalt chrome-on-polyethylene bearing. All patients received the same press-þt hydroxylapatite-coated femoral stem while two-thirds (349 hips) received alumina ceramic bearings and one-third (165 hips) received the cobalt chrome-on-polyethylene bearing. Results: With a mean follow-up of greater than 40 months (36–60 months) there is no signiþcant difference in clinical performance between the two patient cohorts. Radiographically proximal femoral osteolysis has been noted in the control patients but in no patients that received the ceramic bearing. With Continued Access, a total of 947 alumina ceramic bearings have been implanted to date. There have been no ceramic fractures or alumina bearing failures. Conclusions: This new alumina-alumina ceramic bearing provides for a safe option for the younger and more active patient population


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_III | Pages 259 - 259
1 Nov 2002
Streicher R
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Late aseptic loosening of total hip arthroplasty (THA) components due to wear debris especially sub-micron Polyethylene induced osteolysis has been identified to be the major cause for revision. Therefore, the use of wear resistant designs and materials is imperative for the long-term success of articulating implants. One of the most promising articulations for THA regarding extremely low wear is the hard-on-hard Alumina/Alumina combination with a long history in orthopaedics accumulating to now 30 years of experience. Alumina Ceramic: Aluminum-Oxide Ceramic (Alumina, Al2O3, ISO 6474) is an extremely hard material that can only be scratched and also machined and polished by diamond. It has excellent mechanical properties but is brittle as are most ceramic materials and can, therefore, not be used for highly stressed implants like an artificial hip joint stem. Due to its ionic structure it is hydrophilic allowing liquids to bound to and lubricate its surface. Alumina’s hardness allows a polishing to a low roughness, which is entirely inverse and therefore able to create lubricating “pools.”. Density, purity and grain size in combination with an optimised manufacturing process are crucial for the final properties of Alumina and have been sub-optimal at the early pioneering times. Also the design has to be adapted to the critical properties of this ceramic. The biological activity of Alumina is graded as bio-inert and no direct osteointegration is to be expected, also proven by clinical experience. Alpha Alumina is bio-stable and practically insoluble in the body environment. Therefore, ageing or any systemic reaction in the human body with this ceramic is of no concern. First Generation Alumina Ceramic: Boutin has introduced Alumina ceramic components for articulation with itself for THA in 1970, followed by Mittelmeier and other surgeons. First reports of its combination with UHMWPE cups date back to 1972. More than one million Alumina heads have been worldwide implanted since then. Problems regarding fracture of the head were mostly encountered with collared heads of one design and the cup (especially if placed at > 50 deg abduction position). Run-away wear in case of edge contact have been reported with these first generation implants. A comprehensive retrieval study using a systematic analysis of two different designs confirmed that Alumina/ Alumina couples have a low clinical wear rate and identified the main risk factors that can lead to early failure of such devices. The wear rate of those historic Alumina / Alumina articulations is in the range of less than 5 microns per year. This is one to two orders of magnitude less than for any articulation with Polyethylene cups. Reaction to Alumina wear particles, mostly encountered on catastrophic failure of the historic implant designs is sparse and mostly benign. Third Generation Alumina Ceramic: Significant improvements in material properties and quality have been made since its introduction. The third generation of Alumina has been introduced in 1994 and was a further evolution regarding material properties, manufacturing, quality control and design. Refinement of purity, grain size and manufacturing results in improved fracture and also wear resistance, which decreased from low to almost immeasurable values. With the evolution of this new generation ceramic the problems of the past have been successfully addressed. Following improvements are characteristic for a third generation Alumina:. Improved purity and reduced grain size (Figure 1) for better properties. Improved density, HIP for enhanced toughness and bending strength. Less stress raisers due to laser marking instead of mechanical engraving. Optimised head internal geometry. Rounded and polished rim for risk reduction of runaway wear on sub-luxation. Improved safety due to 100% proof test on heads and inserts. These improvements result in a significant increase in mechanical properties. The risk of head fracture has been reduced for this 3rd generation Alumina ceramic heads from 1 per 500 (0.2%) to 1 per 25 000 (0.025%). The wear resistance of the couple Alumina/Alumina has also been enhanced which was measured in simulator tests to be around 1 micron per year. Tribological investigation involved a series of screening, pendulum and anatomical hip simulator tests with actual Alumina/ Alumina components in respect to the effect of clearance and cup angle (45° & 60°) in a series of tests for up to 5 million cycles. Adverse testing conditions for Alumina e.g. dilution of lubricant, dry and water, high load in swing phase, stop-start, etc in ascending aggressiveness (each at 1 million cycles) have also been investigated. No significant difference in wear volume was found comparing clearance or cup angle for all components tested. A new simulator test set up using a microseparation mode during every single cycle was also run for 5 million cycles combining Alumina from one single manufacturer and also mixing Alumina’s from different manufacturers. The wear in all cases was low and lower than for the first generation Alumina’s. A series of implantations with Alumina/Alumina articulation has been performed since November 1996 according to a prospective multicentric FDA IDE protocol comparing the same implant with CoCr metal heads/PE combinations. Short-term results demonstrate no early complications with this third generation Alumina/Alumina articulation if implanted correctly. The benefit of the dramatically reduced wear rate will show only after longer-term follow-up. Conclusion: Alumina/Alumina articulation demonstrates the lowest wear rate of all available material combinations for THA in the laboratory as well as in clinical praxis. The bulk material as well as its particles is bio-inert, therefore, giving no concern for adverse biological reactions. Problems with earlier designs of Alumina/Alumina articulation have been successfully addressed by taking the identified risk parameters into consideration. Components of the third generation Alumina ceramic and design have been extensively tested. All components pass the mechanical tests. Alumina heads and liners of the third generation in the size and under the conditions tested are safe and efficient. Their wear rate even under the influence of adverse condition is minimal. Further clinical trials parallel the application of this superior articulation couple in an innovative and modern design.Alumina/Alumina is, therefore, the material combination of choice for the active patient with high life expectancy


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 4 - 4
1 Jan 2004
D’Antonio J Capello W Manley M Bierbaum B
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Today’s major challenge for total hip arthroplasty is to minimise wear and osteolysis in our younger and more active patients. Alumina ceramic bearings have known superior wear resistance and lubrication and do not carry a risk of ion release. Utilising new improved alumina ceramic materials and implant design 514 hips were implanted in a multicentre US IDE prospective and randomised study. The study compared alumina-on-alumina ceramic bearings to a cobalt chrome-on-polyethylene bearing. All patients received the same press-fit hydroxylapatite coated femoral stem while two-thirds (349 hips) received alumina ceramic bearings and one-third (165 hips) received the cobalt chrome on polyethylene bearing. All patients suffered from non-inflammatory arthritis and were young and active with an average age of 53 years. At a follow-up of 24–60 months (mean 39.8 months) there was no significant difference in clinical performance between the patient cohorts


The Bone & Joint Journal
Vol. 101-B, Issue 4 | Pages 443 - 446
1 Apr 2019
Kurokawa H Taniguchi A Morita S Takakura Y Tanaka Y

Aims. Total ankle arthroplasty (TAA) has become the most reliable surgical solution for patients with end-stage arthritis of the ankle. Aseptic loosening of the talar component is the most common complication. A custom-made artificial talus can be used as the talar component in a combined TAA for patients with poor bone stock of the talus. The purpose of this study was to investigate the functional and clinical outcomes of combined TAA. Patients and Methods. Ten patients (two men, eight women; ten ankles) treated using a combined TAA between 2009 and 2013 were matched for age, gender, and length of follow-up with 12 patients (one man, 11 women; 12 ankles) who underwent a standard TAA. All had end-stage arthritis of the ankle. The combined TAA features a tibial component of the TNK ankle (Kyocera, Kyoto, Japan) and an alumina ceramic artificial talus (Kyocera), designed using individualized CT data. The mean age at the time of surgery in the combined TAA and standard TAA groups was 71 years (. 61. to 82) and 75 years (62 to 82), respectively. The mean follow-up was 58 months (43 to 81) and 64 months (48 to 88), respectively. The outcome was assessed using the Japanese Society for Surgery of the Foot (JSSF) ankle-hindfoot scale, the Ankle Osteoarthritis Scale (AOS), and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q). Results. The mean preoperative JSSF score of the combined TAA and standard TAA groups was 44 (. sd. 11) and 49 (. sd. 10), respectively. The mean postoperative JSSF scores were 89 (. sd. 6.1) and 72 (. sd. 15), respectively. The mean postoperative JSSF score of the combined TAA group was significantly higher (p = 0.0034). The mean preoperative AOS scores for pain and function in the combined TAA and standard TAA groups were 5.8 (. sd. 3.3) and 5.5 (. sd. 3.1), and 8.6 (. sd. 1.3), and 7.1 (. sd. 2.9), respectively. The mean postoperative AOS scores of pain and function were 2.5 (. sd. 2.5) and 2.2 (. sd. 1.9), and 2.5 (. sd. 3.3) and 3.4 (. sd. 2.9), respectively. There were no significant differences between the two groups in terms of postoperative AOS scores. The mean postoperative SAFE-Q scores were: for pain, 76 (. sd. 23) and 70 (. sd. 23); for physical function, 66 (. sd. 25) and 55 (. sd. 27); for social function, 73 (. sd. 35) and 62 (. sd. 34); for shoe-related, 73 (. sd. 19) and 65 (. sd. 26); and for general health, 78 (. sd. 28) and 67 (. sd. 29), respectively. There were no significant differences between the two groups in terms of postoperative SAFE-Q scores. Conclusion. Combined TAA resulted in better clinical results than standard TAA. Cite this article: Bone Joint J 2019;101-B:443–446


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_14 | Pages 18 - 18
1 Nov 2021
Sedel L Bizot P Garcia-Cimbrelo E
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Fracture risks are the most common argument against the use of Ceramic on ceramic (CoC) hip implants. Question: is ceramic material at risk in case of severe local trauma?. Over a long period, we tried to identify patients with a CoC prosthesis (Ceraver Osteal°)who did sustain a trauma. This was conducted in three different institutions. Eleven patients were found: 9 males and 2 females aged 17 to 70 years at time of index surgery. Accident occurred 6 months to 15 years after index: one car accident, five motorcycle accident, five significant trauma after a fall, including one ski board accident. Consequences of these trauma were: six fractures of the acetabulum with socket loosening in 4 that needed revision, two femoral shaft fracture, one orifed and one stem exchanged, one traumatic hip dislocation associated to loosening of the socket revised at 10 years, and one traumatic loosening of the socket. Ten had no consequence on ceramic integrity. One experienced a fracture of the patella from a dashboard trauma, a liner shipping was discovered during socket revision 2 years later. This is the only case of possible relation between trauma and ceramic fracture. In a more recent longitudinal study on 1856 CoC prosthesis performed from 2010 to 2021, 29 severe traumas were identified with no consequence on Ceramic material. From this limited case study, it can be assumed that Pure Alumina Ceramic well designed and manufactured, will not break after a significant trauma


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_10 | Pages 12 - 12
1 Jun 2018
Lachiewicz P
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Key Points:. Historically, 22.25, 26, 28, or 32 mm metal femoral heads were used in primary total hip arthroplasty, but innovations in materials now permit head sizes 36 mm or larger. Stability and wear of primary total hip arthroplasty are related to the diameter and material of the femoral head. Larger diameter femoral heads are associated with increased joint stability through increases in arc range of motion and excursion distance prior to dislocation. Fixation of the acetabular component may be related to the size of the femoral head, with increased frictional torque associated with large diameter heads and certain polyethylene. Linear wear of highly crosslinked polyethylenes seems unrelated to femoral head diameter, but larger heads have been reported to have higher volumetric wear. Mechanically assisted crevice corrosion at the connection between the modular femoral head and neck may be associated with the femoral head size and material. Cobalt chromium alloy, alumina ceramic composite, or oxidised zirconium femoral heads on highly crosslinked polyethylene are the most commonly used bearing surfaces, but each may have unique risks and benefits. Conclusions. At present, there is a wave of enthusiasm for the routine use of “large” (32, 36 mm, or larger) femoral heads with highly crosslinked polyethylene for the vast majority of patients having a primary THA. It may be reasonable to consider the “graduated femoral head-outer acetabular diameter system”, using 28 mm femoral heads with “smaller” acetabular components (<50 mm), 32 mm femoral heads with acetabular components 50 – 56 mm outer diameter, and 36 mm or larger femoral heads with acetabular components 58 mm or larger in diameter, to minimise both the risk of dislocation and the frictional torque. Although the linear wear of highly crosslinked polyethylene appears to be independent of head size, the reported increase in volumetric wear with large femoral heads and highly crosslinked polyethylene requires further study, and should temper the use of femoral heads 36 mm or larger in younger and more active patients. With its long and successful history, it is difficult to recommend the complete abandonment of the cobalt chromium alloy femoral head in all patients having a primary THA. Alumina ceramic or oxidised zirconium heads may be considered for younger, heavier, and more active patients, who seem to have the highest risk of trunnion corrosion. Surgeons and patients should be aware of the unique possible complications of these two newer femoral head materials


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 139 - 139
1 Mar 2010
Sariali* E Stewart* T Jin* Z Fisher* J
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Introduction: The goal of the study was to compare the squeaking frequencies of Ceramic-on-Ceramic THR in-vitro and in-vivo among patients who underwent THR. Method: Four patients, who underwent THR with a Ceramic-on-Ceramic THR (Trident. ®. , Stryker. ®. ) presented a squeaking noise. The noise was recorded and analysed with acoustic software (FMaster. ®. ). In-vitro 2 alumina ceramic (Biolox Forte Ceramtec. ®. ) 32 mm diameter (Ceramconcept. ®. ) components were tested using a PROSIM. ®. hip friction simulator. The cup was positioned with a 70° abduction angle in order to achieve edge loading conditions and the head was articulated ± 10° at 1 Hz with a load of 2.5kN for a duration of 300 cycles. Tests were conducted under lubricated conditions with 25% bovine serum and with the addition of a 3rd body alumina ceramic particle (200 μm thickness and 2 mm length). Results: In-vivo, recordings had a dominant frequency ranging between 2.2 and 2.4 kHz. In-vitro no squeaking occurred under edge loading conditions. However, with the addition of an alumina ceramic 3rd body particle in the contact region squeaking was obtained at the beginning of the tests and stopped after ~20 seconds (dominant frequency 2.6 kHz). Discussion and Conclusion: Squeaking noises of a similar frequency were recorded in-vitro and in-vivo. In-vitro noises followed edge loading and 3rd body particles and despite, the severe conditions, squeaking was intermittent and difficult to reproduce. The lower frequency of squeaking recorded in-vivo, demonstrates a potential damping effect of the soft tissues. No damage was observed on the components, however, the test duration was very short. Squeaking may be related to third body particles that could be generated by wear or impingement between the femoral neck and the metal back. Cup design seems to be of particular importance in noisy hip, leading to a high variability of squeaking rate according to the implants


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_III | Pages 259 - 260
1 Nov 2002
Fisher J
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Traditional hip prostheses, which involve metal on poly-ethylene articulations, have shown good survivorship at ten years, but in the long term, wear debris induced osteolysis has been found to cause loosening and failure. Specifically, micron and submicron size polyethylene wear particles generated at the articulating surfaces enter the periprosthetic tissues, activate the macrophages causing adverse cellular reactions and bone resorption. Recent laboratory, retrieval and clinical studies have shown that oxidation of the traditional polyethylene irradiated in air, causes wear to increase by a factor of three following either storage on the shelf for five years or following implantation in vivo for 15 years. Furthermore, damage or scratching of metallic femoral heads has been shown to increase wear by a factor of two. In vitro cell culture studies with real polyethylene wear particles, have shown that the intensity of the adverse cellular reactions is critically dependent on the size of the polyethylene wear particle with the smallest particles 0.1 to 1 mm being the most active. A novel model has been developed to predict functional biological activity and osteolytic potential, by integrating wear rates, particle analysis and cell culture studies. Stabilised and crosslinked polyethylenes have been investigated and been found to reduce wear rates by a factor of three compared to oxidised and aged materials. A moderate level of crosslinking reduced wear from 50 to 35 mm3 per million cycles compared to non crosslinked materials. However, against scratched femoral heads, the wear rate of both stabilised and cross-linked polyethylene was elevated to levels where the functional biological activity remains a concern in the long term. Alternative bearing surfaces, metal on metal, and alumina ceramic on ceramic provide potential to substantially reduce wear. Metal on metal bearings have shown mean wear rates of 1.5 mm3/year in the hip joint simulator, with very small, 30 nm size particles. Alumina ceramic ceramic have also shown very low wear rates of approximately 1 mm3/year, even in the presence of microseparation and rim contact, with small 10 nm size wear particles and larger particles up to 1 mm in size caused by grain boundary fracture. The functional biological activity and osteolytic potential of the alumina ceramic couple is predicted to be at least ten times lower than crosslinked polyethylene. New ceramic materials (zirconia toughened alumina) have been shown to further reduce ceramic ceramic wear. Furthermore, novel differential hardness ceramic on metal bearings have shown even lower wear rates. The currently available hard on hard bearings and the recent further improvements of these bearing couples, indicate that osteolysis free lifetimes well beyond 20 years are now possible


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXV | Pages 56 - 56
1 Jun 2012
El-Hadi S Stewart T Jin Z Fisher J
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INTRODUCTION. Squeaking after total hip replacement has been reported in up to 10% of patients. Some authors proposed that sound emissions from squeaking hips result from resonance of one or other or both of the metal parts and not the bearing surfaces. There is no reported in vitro study about the squeaking frequencies under lubricated regime. The goal of the study was to reproduce the squeaking in vitro under lubricated conditions, and to compare the in vitro frequencies to in vivo frequencies determined in a group of squeaking patients. The frequencies may help determining the responsible part of the noise. METHODS. Four patients, who underwent THR with a Ceramic-on-Ceramic THR (Trident(r), Stryker(r)) presented a squeaking noise. The noise was recorded and analysed with acoustic software (FMaster(r)). In-vitro 3 alumina ceramic (Biolox Forte Ceramtec(r)) 32 mm diameter (Ceramconcept(r)) components were tested using a PROSIM(r) hip friction simulator. The cup was positioned with a 75° abduction angle in order to achieve edge loading conditions. The backing and the cup liner were cut with a diamond saw, in order to avoid neck-head impingement and dislocation in case of high cup abduction angles (Figure1). The head was articulated ± 10° at 1 Hz with a load of 2.5kN for a duration of 300 cycles. The motion was along the edge. Tests were conducted under lubricated conditions with 25% bovine serum without and with the addition of a 3. rd. body alumina ceramic particle (200 μm thickness and 2 mm length). Before hand, engineering blue was used in order to analyze the contact area and to determine whether edge loading was achieved. RESULTS. Edge loading was obtained. In-vitro, no squeaking occurred under edge loading conditions. However, with the addition of an alumina ceramic 3. rd. body particle in the contact region squeaking was obtained at the beginning of the tests and stopped after ∼20 seconds (dominant frequency 2.6 kHz). In-vivo, recordings had a dominant frequency ranging between 2.2 and 2.4 kHz. DISCUSSION. For the first time, squeaking was reproduced in vitro under lubricated conditions. In-vitro noises followed edge loading and 3. rd. body particles and despite, the severe conditions, squeaking was intermittent and difficult to reproduce. However, squeaking is probably more difficult to reproduce because the cup was cut and the head was fixed in the simulator, preventing vibration to occur. Squeaking noises of a similar frequency were recorded in-vitro and in-vivo. The lower frequency of squeaking recorded in-vivo, demonstrates a potential damping effect of the soft tissues. Therefore, the squeaking in the patients was probably related to the bearing surfaces and modified lubrication conditions that may be due to edge loading. Varnum et al reported recently (3) that all the revised squeaking patients had a neck-cup impingement with metal 3. rd. body particles. These metallic wear particles may generate squeaking as shown in vitro. However, a larger cohort of squeaking patients is needed to confirm these results


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_IV | Pages 529 - 529
1 Oct 2010
Sariali E Fisher J Jin Z Stewart T
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Introduction: Squeaking after total hip replacement has been reported in up to 10% of patients. Some authors proposed that sound emissions from squeaking hips result from resonance of one or other or both of the metal parts and not the bearing surfaces. There is no reported in vitro study about the squeaking frequencies under lubricated regime. The goal of the study was to reproduce the squeaking in vitro under lubricated conditions, and to compare the in vitro frequencies to in vivo frequencies determined in a group of squeaking patients. The frequencies may help determining the responsible part of the noise. Methods: Four patients, who underwent THR with a Ceramic-on-Ceramic THR (Trident. ®. , Stryker. ®. ) presented a squeaking noise. The noise was recorded and analysed with acoustic software (FMaster. ®. ). In-vitro 3 alumina ceramic (Biolox Forte Ceramtec. ®. ) 32 mm diameter (Ceramconcept. ®. ) components were tested using a PROSIM. ®. hip friction simulator. The cup was positioned with a 75° abduction angle in order to achieve edge loading conditions. The backing and the cup liner were cut with a diamond saw, in order to avoid neck-head impingement and dislocation in case of high cup abduction angles. The head was articulated ± 10° at 1 Hz with a load of 2.5kN for a duration of 300 cycles. The motion was along the edge. Tests were conducted under lubricated conditions with 25% bovine serum without and with the addition of a 3rd body alumina ceramic particle (200 μm thickness and 2 mm length). Results: Edge loading was obtained incompletely. In-vitro, no squeaking occurred under edge loading conditions. However, with the addition of an alumina ceramic 3rd body particle in the contact region, squeaking was obtained at the beginning of the tests and stopped after ~20 seconds (dominant frequency 2.6 kHz). In-vivo, recordings had a dominant frequency ranging between 2.2 and 2.4 kHz. Discussion: For the first time, squeaking was reproduced in vitro under lubricated conditions. In-vitro noises followed edge loading and 3rd body particles and despite, the severe conditions, squeaking was intermittent and difficult to reproduce. However, squeaking is probably more difficult to reproduce because the cup was cut and the head was fixed in the simulator, preventing vibration to occur. Squeaking noises of a similar frequency were recorded in-vitro and in-vivo. The lower frequency of squeaking recorded in-vivo, demonstrates a potential damping effect of the soft tissues. Therefore, the squeaking in the patients was probably related to the bearing surfaces and modified lubrication conditions that may be due to edge loading. The determined values of frequencies may help to analyze the squeaking patients in order to determine the mechanism generating the sound


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 12 | Pages 1567 - 1573
1 Dec 2006
Kovac S Trebse R Milosev I Pavlovcic V Pisot V

We present a retrospective series of 170 cemented titanium straight-stem femoral components combined with two types of femoral head: cobalt-chromium (CoCr) alloy (114 heads) and alumina ceramic (50 heads). Of the study group, 55 patients (55 stems) had died and six (six stems) were lost to follow-up. At a mean of 13.1 years (3 to 15.3) 26 stems had been revised for aseptic loosening. The mean follow-up time for stable stems was 15.1 years (12.1 to 16.6). Survival of the stem at 15 years was 75.4% (95% confidence interval (CI) 67.3 to 83.5) with aseptic failure (including radiological failure) as the end-point, irrespective of the nature of the head and the quality of the cement mantle. Survival of the stem at 15 years was 79.1% (95% CI 69.8 to 88.4) and 67.1% (95% CI 51.3 to 82.9) with the CoCr alloy and ceramic heads, respectively. The quality of the cement mantle was graded as a function of stem coverage: stems with complete tip coverage (type 1) had an 84.9% (95% CI 77.6 to 92.2) survival at 15 years, compared with those with a poor tip coverage (type 2) which had a survival of only 22.4% (95% CI 2.4 to 42.4). The poor quality of the cement mantle and the implantation of an alumina head substantially lowered the survival of the stem. In our opinion, further use of the cemented titanium alloy straight-stem femoral components used in our series is undesirable


The Journal of Bone & Joint Surgery British Volume
Vol. 85-B, Issue 5 | Pages 655 - 660
1 Jul 2003
Tanaka K Tamura J Kawanabe K Shimizu M Nakamura T

We examined the behaviour of alumina ceramic heads in 156 cemented total hip arthroplasties, at a minimum follow-up of eight years. They were divided into three groups according to the size of the femoral head; 22, 26, and 28 mm. We measured polyethylene wear radiologically using a computer-aided technique. The linear wear rate of polyethylene sockets for the 28 mm heads was high (0.156 mm/year), whereas those for the 22 and 26 mm heads were relatively low (0.090 and 0.098 mm/year, respectively). Moreover, the surface roughness data of retrieved femoral heads clearly showed maintenance of an excellent surface finish of the current alumina. We conclude that the alumina ceramic femoral heads currently used are associated with a reduced rate of polyethylene wear


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 157 - 157
1 Mar 2008
Bierbaum BE D’Antonio J Capello W Manley M Deshmukh R
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A major challenge for total hip arthroplasty is to minimize wear and osteolysis in young, active patients. Alumina ceramic bearings have shown superior wear resistance and lubrication and do not carry the risk of ion release. In a prospective randomized study (ABC), 514 hips were implanted. All patients (average age, 53 years) received the same press-fit hydroxyapatite coated femoral stem; two thirds (345 hips) received alumina ceramic bearings, and one third (169 hips) received a cobalt-chrome-on-polyethylene bearing. A fourth arm (Trident) was included involving use of a metal-backed acetabular component implanted in 209 patients. At a mean follow-up of 35.2 months (range, 24–48 months), there was no significant difference in clinical performance between the patient cohorts. The cohort of patients included in the ABC, Trident, and extended access portion of the study represents a population of 2313 patients with no device related failures attributable to the ceramic on ceramic articulation used in these patients. This new experience involves the use of improved ceramic materials and new design considerations that eliminate the risks and complications of past experiences with ceramic implants and provides a safe bearing option for young patients


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 25 - 25
1 Sep 2012
Chana R Tilley S Facek M Walter W Zicat B Walter W
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Aim. Alumina ceramic on ceramic bearings in total hip arthroplasty (THA) may reduce the prevalence of osteolysis due to its properties of low wear and chemical inertness. This is critical in the younger patient population as they place increased demands over a longer period. This study reports on the clinical and radiographic outcomes of a series of modern cementless ceramic on ceramic THA at a minimum of 10 years in this younger group. Method. A series of 120 consecutive third generation ceramic cementless THA were performed at a single centre in 110 patients from 1997 to 1999. The average age of the patients at the time of surgery was 45 years (20 to 55 years). All procedures were carried out via the posterior approach using the same implant by the two senior authors. Results. At 10 years, 4 patients had died and 6 were lost to follow-up (5%). The mean Harris Hip Score was 94.7 points. All surviving implants analysed radiographically had evidence of stable bony ingrowth, with no cases of osteolysis. Wear rates were undetectable. There were 3 revisions (2.5%). One stem was revised following periprosthetic fracture, one stem was revised to facilitate a femoral shortening osteotomy. One cup was revised for anterior impingement causing psoas tendonitis. There was one incident of intraoperative ceramic liner chipping, which was changed without complication. There were no postoperative bearing fractures. Two patients reported intermittent squeaking at extreme hip flexion and internal rotation, the hips otherwise functioned well. The survival for both components with revision for any cause was 97.5%. Conclusion. Alumina ceramic on ceramic bearings in cementless primary THA in this series have resulted in good clinical and radiographic outcomes with low wear rates and excellent function in the demanding younger patient group at 10 years


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_3 | Pages 108 - 108
1 Jan 2016
Yamane S Oonishi H Kyomoto M Iwamoto M Kawahara I Hanaoka Y Oonishi H
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One of serious issues in total hip arthroplasty (THA) is the osteolysis which results in aseptic loosening caused by the wear particles from a polyethylene (PE) acetabular cup. In addition, oxidation degradation of PE cup resulting in the fracture or the severe wear caused by the reduction of mechanical properties in vivo is also the issue. The oxidation degradation is considered to be induced by residual free radicals generated by gamma-ray irradiation for cross-linking to reduce wear or for sterilization. In this study, (1) wear property, (2) oxidation degradation of retrieved PE and highly cross-linked PE (CLPE) cups against alumina ceramic femoral heads, and (3) the correlation between those properties were evaluated. The radiographic wear of six conventional PE cups with the mean follow-up of 19.1–23.3 years and 60 CLPE cups with the mean follow-up of 3.1–9.1 years were measured by a non-radiostereometric analysis method (Vectorworks. ®. 10.5 software package). As a retrieval analysis, 26 retrieved acetabular cups were evaluated; 16 cups were ethylene oxide gas-sterilized conventional PE cups with clinical use for 16.0–24.9 years and 10 cups were gamma-ray-sterilized CLPE cups with clinical use for 0.9–6.7 years. The linear and the volumetric wear were measured using a three-dimensional (3D) coordinate measurement machine. The shapes of unworn and worn surfaces with 15- and 30-point intervals, respectively, were measured. Oxidation degradation of the surface, sub-surface and inner for both worn and unworn parts of the retrieved cups was measured using a Fourier-transform infrared (FT-IR) spectroscopy. Oxidation indices were calculated using the peak at 1740 cm. −1. and 1370 cm. −1. according to ASTM F2012. In the radiographic analysis, the linear wear rate of CLPE cups was significantly lower than that of conventional PE cups [Fig. 1]. In the retrieval analysis, the linear wear rate of CLPE cups (mean: 0.07 mm/year) showed a 51% reduction (p = 0.002) compared to conventional PE cups (mean: 0.14 mm/year) [Fig. 2]. The retrieval and the radiographic analysis for both conventional PE and CLPE cups showed similar results (p = 0.7 and 0.1, respectively). Maximum oxidation indices for CLPE cups were similar to those of conventional PE cups regardless of the difference of clinical duration [Fig. 3]. This result is different from in vivo wear, which increases as the clinical duration. For both conventional PE and CLPE cups, the oxidation indices of subsurface were higher than those for surface. The worn parts showed higher oxidation indices than those for unworn parts. From the results, even when the free radicals were so few or absent, the oxidation degradation would be induced in vivo. In conclusion, the wear resistance for CLPE cups was greater than that for conventional PE cups from both radiographic and retrieval analyses. The in vivo oxidation degradation might not be caused by only residual free radicals. It was found that oxidation degradation of PE cups when used with alumina ceramic femoral heads is not correlated to their wear properties


The Journal of Bone & Joint Surgery British Volume
Vol. 91-B, Issue 11 | Pages 1533 - 1535
1 Nov 2009
Salih S Currall VA Ward AJ Chesser TJS

Surgeons remain concerned that ceramic hip prostheses may fail catastrophically if either the head or the liner is fractured. We report two patients, each with a ceramic-on-ceramic total hip replacement who sustained high-energy trauma sufficient to cause a displaced periprosthetic acetabular fracture in whom the ceramic bearings survived intact. Simultaneous fixation of the acetabular fracture, revision of the cementless acetabular prosthesis and exchange of the ceramic bearings were performed successfully in both patients. Improved methods of manufacture of new types of alumina ceramic with a smaller grain size, and lower porosity, have produced much stronger bearings. Whether patients should be advised to restrict high-impact activities in order to protect these modern ceramic bearings from fracture remains controversial


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 431 - 431
1 Apr 2004
Bergman N Young D
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A prospective consecutive series of uncemented, hydroxyapatite coated primary hip replacements utilizing two different types of alumina ceramic inserts and alumina ceramic heads is reported. Clinical and radiological results together with complications and reoperations are detailed. 193 hips followed up to 39 months using the Secur fit cup with ABC liner (Stryker). 40 hips using the Trident AD shell with the Trident titanium wrapped liner are reported up to 18 months. Clinical scores (Harris and Postel Merle D’Aubigne) are similar to metal polyethylene at early review. SF 12 physical scores improved post operation. 100% bony ingrowth was seen radiologically (Engh and ARA scores). Liner rim surface chips on insertion were seen in 1.4% of the ABC liners and none occurred after the 20th hip. No chips were seen in the Trident liners. One ABC liner sustained extensive surface rim chips in a heavy fall at 24 months. This is the first report of such a liner fracture. One Secur fit ABC cup was revised for recurrent subluxation. The importance of early revision of ceramic fractures and the re use of shells is discussed. The addition of a titanium sandwich wrap to the ceramic liner is likely to eliminate the early chips


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 12 | Pages 1656 - 1658
1 Dec 2006
Hatano H Morita T Kobayashi H Otsuka H

Despite extensive experience with prosthetic replacement for the reconstruction of limbs following juxta-articular resection of tumours, there are few reports of prosthetic replacement of the distal radius. We present two cases of massive bone defects of the distal radius in which alumina ceramic prosthetic replacements were used. We evaluated the patients more than ten years after the procedure. Both patients had degenerative changes to the wrist. This, however, was not associated with pain or decreased function, and both had returned to their previous occupation after surgery. When a patient has a massive defect of the distal radius, reconstruction using a ceramic prosthesis is a reasonable alternative to using autograft. This method of treatment results in little pain, a moderate range of movement and satisfactory function


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 95 - 95
1 Dec 2013
Streicher R Scheuber L Sylvia U Kaddick C Hintner M
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Introduction. From a tribological point of view and clinical experience, a ceramic-on-ceramic bearing represents the best treatment option after rare cases of ceramic component fracture in total hip arthroplasty (THA). Fractured ceramic components potentially leave small ceramic fragments in the joint capsule which might become embedded in PE acetabular liners. Purpose. This in vitro study compared for the first time the wear behaviour of femoral ball heads made of ceramic and metal tested with PE liners in the presence of ceramic third-body debris. The contamination of the test environment with third-body ceramic debris, insertion of ceramic fragments into the PE liners and implementation of continuous subluxation simulated a worst-case scenario after revision of a fractured ceramic component. Materials and Methods. Ceramic femoral ball heads (ϕ 32 mm) made of alumina matrix composite (AMC; BIOLOX® delta, CeramTec, Germany) were tested in combination with PE and cross-linked liners and compared to metal femoral ball heads (CoCrMo) of the same diameter. All PE liners were fixed into Ti-6Al-4V metal shells by conical fixation as intended for clinical use. The tests were performed based on ISO 14242-1 utilizing a hip simulator (EndoLab, Germany). Alumina ceramic debris (BIOLOX® forte, CeramTec, Germany) of about 2 mm diameter (maximum 5 mm) were inserted into the PE liners in predefined specific points corresponding to the main load transfer area before the test. The acetabular liners were tested at an inclination of 45° in the medial-lateral plane with the specimens placed in an anatomically correct position. During the test, additional alumina ceramic debris was introduced into the articulation area as a part of the test fluid (calf serum) used in the simulator test chambers. All specimens were tested up to 5 million cycles. Damages to the surfaces of the materials were assessed visually. The wear of the femoral ball heads was measured gravimetrically. Results. High wear rates were found for metal femoral ball heads, being 1,010 times higher when compared to ceramic femoral ball heads tested with XPE liners and 560 times higher when compared to ceramic femoral ball heads tested with conventional PE liners. The conventional and crosslinked PE liners used in combination with metal femoral ball heads clearly exhibited a scratched surface, whereas the surface of the liners tested with ceramic femoral ball heads exhibited significantly less scratching. Discussion and Conclusion. This study demonstrates that apart from the recommended ceramic-on-ceramic option also ceramic-on-PE and ceramic-on-crosslinked PE bearing couples may be a viable treatment option after fracture of a ceramic component. The use of a ceramic femoral ball head after fracture of a ceramic articulation component minimizes wear and wear-related complications caused by third-body wear. Based on the results of this in vitro study and clinical findings, the use of a metal femoral ball head in articulation with any PE liner after a ceramic fracture is contraindicated


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 10 - 11
1 Jan 2004
Oonishi H Kim S Clarke I Asano T Bal B Kyomoto M Masuda S
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According to the knee simulator test results in 1970s, the total decrease in thickness of UHMWPE tibial tray in combination with ceramic femoral component [F-Comp] was less than one tenth as that of the combination with metal [. 1. ]. These advantages led to development of total knee prosthesis [TKP] with alumina ceramics. In this study, we report the wear surface observation, the clinical wear and the oxidation of the retrieved TKP used clinically for 23 years, comparing with a metal TKP. The retrieved TKP was implanted in 1979, and retrieved on January 9th in 2002. This TKP consisted of an alumina ceramic F-Comp and a UHMWPE tray combined with a alumina ceramic tibial component. Observations of the surface of alumina F-Comp and UHMWPE tray were carried out using SEM. Shape of UHMWPE tray was determined three-dimensionally. Comparing the result with original shape based on the product’s plan, liner wear and volumetric wear were calculated. Oxidation index was determined by Fourier transform infrared spectrophotometry. Alumina F-Comp did not have any scratch on the surface by seeing with naked eye. UHMWPE tray had deformation and scratches obviously. The liner wear rate was 37 micrometer/year and volumetric wear rate was 18.8 mm3/year. The oxidation indexes were 0.6 in the unworn area, 1.2 in the worn area and 0.2 in the inner area. SEM observations of the F-Comp demonstrated no scratch or pit. In contrast, many scratches were clearly observed on the UHMWPE tray. However, higher magnification observations did not demonstrate severe wear, which was shown on the wear analysis of a metallic F-Comp. Oxidation degradation is a problem to solve. However, the low wear rate and mild wear pattern demonstrate that ceramic F-Comp reduced UHMWPE wear


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 8 - 8
1 Jan 2004
Williams S Stewart T Ingham E Stone M Fisher J
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Following total hip replacement surgery, fluroscopy studies have shown that a mean separation of 2 mm can occur between CoCr femoral heads and UHMWPE acetabular cups during the swing phase of gait [. 1. ]. In vivo and in vitro studies [. 2. , . 3. ] of alumina ceramic on ceramic hip replacements have demonstrated that swing phase microseparation followed by the impact of the femoral head on the acetabular insert rim can lead to accelerated wear. However, wear remains low. A similar trend was observed when metal on metal hip replacements were tested under microseparation conditions [. 4. ]. The purpose of the current study was to examine the wear of ceramic on polyethylene bearings under standard and microseparation conditions. A physiological hip simulator was used, loads and motions were applied to approximate in vivo conditions. The alumina ceramic heads and polyethylene cups were 28 mm in diameter and were tested for 5 million cycles in 25% new born calf serum at 1 Hertz. Microseparation was achieved by displacing the femoral head inferiorly during swing phase, where the head contacted the inferior cup rim and was laterally displaced. On heel strike the head contacted the superior cup rim prior to relocation. The volumetric wear of the polyethylene inserts was approximately four times less under microseparation conditions (5.6 ± 5.3 mm3 per million cycles), in comparison to standard conditions (25.6 ± 5.3 mm3 per million cycles). Deformation of the cup rim was observed, but some of this was attributed to creep. It is postulated that this reduction in wear was due to the separation of the components in swing phase improving the entrapment of lubricant, hence reducing wear via a squeeze film lubrication mechanism. In conclusion, surgical procedures that produce a small and controlled amount of joint laxity and microseparation may lead to a reduction in wear of the polyethylene acetabular cups


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 4 - 5
1 Jan 2004
Capello W D’Antonio J Bonutti P Manley M
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Utilising a new implant design and improved alumina ceramic materials, 514 hips were implanted in a US IDE prospective, randomised study. All patients received the same press-fit hydroxylapatite (HA) coated femoral stem. Two-thirds (349 hips) received alumina ceramic bearings, and one-third (165 hips) received CoCr heads on polyethylene liners. The alumina group was further divided. Approximately one-half (172 hips – System I) received a porous-coated titanium shell and an alumina insert, and one-half (177 hips – System II ) received a HA-coated, arc-deposited titanium shell and an alumina insert. System III (the control) consisted of a porous-coated titanium shell and a polyethylene insert. External geometry of all shells was identical. An independent orthopaedic surgeon who did not participate in the study reviewed all radiographs. At latest follow-up, (minimum 2 years; range 2-4 years), differences were noted in the developmental pattern of the radiolucent line around the acetabular component. Radiolucent lines were most often noted with System I and System III (porous acetabular shells) in De Lee and Charnley Zone 3 and were absent in System II (arc-deposited titanium with HA) (p=0.001). Other standard radiographic parameters evaluated were found to be comparable, with one exception: In 10 cases in the control group, the development of a small erosive lesion (scalloping) in femoral Gruen Zone 8 was observed on the lateral film. This compares to two cases in System I, and no cases in System II (p=0.001). Dislocation rates were comparable for all three Systems. Seven acetabular components were revised: one in System I, three in System II and System III. The two revisions for aseptic loosening were both in the control group


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 430 - 430
1 Nov 2011
Walter WL
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Ceramic on ceramic articulations had been used since 1970s but with high failure rate. More recent third generation alumina ceramic had improved results due to better material properties to resist wear and fracture and better methods of fixation with metal back acetabular components. A new clinical problem of squeaking has emerged in the last decade and is now a relatively common occurrence in ceramic on ceramic total hip arthroplasty, with a reported incidence from less than 1% to 20% depending on the definition of the noise. We report experience with over 3000 ceramic-on-ceramic hips including the 10 year minimum follow-up of the first 301 cases. Methods: Between June 1997 and Feb 1999, 301 consecutive primary cementless hip arthroplasties were performed on 283 patients under the care of the two senior authors. The mean age of the patients was 58. All patients are asked on follow-up as part of a questionnaire: Has your hip ever made a squeaking noise? To date of the more than 3000 ceramic on ceramic hips that we follow, 74 hips (71 patients) responded yes to this question. Patient demographic and outcome data were analysed in all squeaking hips and compared with all primary ceramic on ceramic hips operated on at our unit. Results: Of the first 301 cases there have been 9 revision surgeries in 8 hips as follows. Two acetabular components revised for psoas tendonitis, one of these subsequently had both components revised for acetabular osteolysis with femoral revision to improve anteversion. There were six other femoral component revisions: four for periprosthetic femoral fractures, one for aseptic loosening and one for transient sciatic nerve palsy. There has been one squeaking hip in this group not requiring revision due to the mild and intermittent nature of the noise. All complications occurred within the first 3 years, no further complication has arisen since. When comparing the 74 squeaking hips to the entire cohort of primary hips we found that taller, heavier and younger patients are significantly more likely to have hips that squeak. Squeaking hips have a significantly higher range of post-operative movement than silent hips. Squeaking hips have a significantly higher Harris hip score. There was no difference in the satisfaction scores between squeaking and silent hips. Conclusion: In summary, we have reported the large series of third generation alumina ceramic on ceramic articulation with 10 year results, and have demonstrated that it can produce excellent survivorship with good clinical and radiographic outcome. We believe that this result had provided very encouraging evidence to support the use of third generation ceramics as articulation for primary hip arthroplasty, especially in young and active patients


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXV | Pages 26 - 26
1 Jun 2012
Su E Chotai P
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Introduction. Alumina Ceramic liners are increasingly used in patients undergoing Total Hip Replacement (THR). The rate of fracture of ceramic liner is decreasing with improved manufacturing techniques from 1. st. to 3. rd. generation alumina-ceramic liners. We report the first case of a fracture of a modern, 4. th. generation alumina bearing ceramic liner, which incorporates a metal sheath to help avoid fracture. Our case is a 60 years old female presenting two years and three months after a bilateral total hip replacement using Stryker Trident cup, securfit stem and alumina on alumina bearing ceramic liner. Ceramic liners are commonly used, especially in young patients because of their excellent biocompatibility, low wear rate and superior tribology. Although fracture of ceramic liner is a less common complication of modern total hip arthroplasty, it is a major concern with the use of ceramic on ceramic THR, the reason being brittleness of ceramic. Cases of 3. rd. generation ceramic liner fracture have been reported which might be associated with impingement due to excessive anteversion of the socket in Asian patients who habitually squat. Habitual squatting, sitting cross legged and kneeling were not characteristic of this case. Methods. The patient presented with complains of mechanical grinding in left hip. She also reported a past history of clicking sound from left hip on extension of left hip and long stride gait. There was no history of trauma or fall. On examination she had a nonantalgic gait and left hip had audible and palpable crepitations. The range of motion on left hip was intact with no subluxation. Right hip was symptom free and examination did not detect any abnormalities. Evaluation & Results. Radiographs of left hip revealed eccentric positioning of the head [Fig. 1] within the socket and excessive anteversion of the socket, which likely caused edge-loading in extension, leading to catastrophic failure in form of fracture of ceramic liner on left hip. She was treated with revision surgery using polyethylene liner with metal head. Intra-operative findings confirmed the ceramic liner fracture [Fig. 2] and revealed impingement of the metal neck against the metal rim of the liner. Discussion & Conclusion. Although ceramic on ceramic hips have excellent wear properties, it is subject to fracture due to its brittle nature. This can lead to catastrophic failure with edge loading. In this case, the alumina-ceramic liner fractured; despite of being surrounded by a metal rim to prevent fracture. It fractured at the anterior edge, which is where it was loaded in extension. We believe that careful attention must be paid not only to inclination, but version of the socket, so as to avoid this complication. Other factors which might lead to such complication are obesity, high activity level, improper manufacturing teachniques for ceramic liners and entrapment and impingement of a micromm sized foreign body between ceramic liner and prosthetic head which initiates wear


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_II | Pages 221 - 221
1 May 2011
Masson B Pandorf T
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The introduction of ceramics in total hip arthroplasty contributed significantly to the wear reduction of poly-ethylene and in consequence reduced osteolysis and loosening. This great benefit has been demonstrated in several clinical observations. In a recent study from Norway, the wear of a 28mm alumina and a CrCo ball head against Ultra High Molecular Weight Polyethylene (UHMWPE) after 10 years is compared using the RSA method of wear measurement. It was concluded that the considerable reduced wear for ceramic ball heads in comparison to CrCo ball heads is a great advantage in hip arthroplasty. A first prospective, randomized study with a 15 years follow up has been presented recently in the EFORT 2009. The comparison of wear of polyethylene between alumina and metal ball head shows a reduction of 44% penetration (linear wear) with the alumina-polyethylene bearing surface. In order to offer improved mechanical resistance and tribological qualities than alumina whilst maintaining structural stability, a new generation of alumina matrix composite (BIOLOX. ®. delta) has been used in orthopedics since 2001. The topic of this study is to demonstrate the excellent wear performance of the alumina ceramic composite against polyethylene, compared to alumina/PE in vivo. Methods: The BIOLOX. ®. delta-PE bearing has been tested on a six station hip simulator (Endolob, Rosenheim) according to ISO/DIS 14242. The newborn calf serum was replaced every 0.5 million cycles and the test was stopped after 5 million cycles. Weight was measured using a high precision balance (Sartorius BP 211D). Results and Discussion: After 5 million cycles, the insert surface appeared polished with fine scratching on the whole contact area. The wear rates calculated by linear interpolation were 13,52 mg per million cycles. (Standard deviation 0,60). The wear rate measured for BIOLOX. ®. delta against UHMWPE was 13,52 mg per million cycles. In general, the wear rate can be regarded as small compared to other hip simulator tests using ceramic against polyethylene couplings. When comparing the results for BIOLOX. ®. forte on polyethylene with the same 28mm diameter and same testing parameter, we observed 26,57 +/− 3,55mg/million and 16,08+/−2,31 mg/million, respectively. The BIOLOX. ®. delta on UHMWPE bearing shows improved wear behavior with a much lower wear rate. Conclusion: This study demonstrates the very low in vitro wear of the Alumina ceramic composite on UHMPE compared to ball heads made of pure alumina. Based on this results and the clinical performance of the alumina-UHMPE bearing from the literature, we can expect a further reduction of wear for the BIOLOX. ®. delta on UHMWPE in vivo that will increase the survival rate of the total hip arthroplasty


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 2 | Pages 196 - 201
1 Feb 2010
Hallan G Dybvik E Furnes O Havelin LI

The Norwegian Arthroplasty Register has shown that several designs of uncemented femoral stems give good or excellent survivorship. The overall findings for uncemented total hip replacement however, have been disappointing because of poor results with the use of metal-backed acetabular components. In this study, we exclusively investigated the medium-to long-term performance of primary uncemented metal-backed acetabular components. A total of 9113 primary uncemented acetabular components were implanted in 7937 patients between 1987 and 2007. These were included in a prospective, population-based observational study. All the implants were modular and metal-backed with ultra-high-molecular-weight polyethylene liners. The femoral heads were made of stainless steel, cobalt-chrome (CoCr) alloy or alumina ceramic. In all, seven different designs of acetabular component were evaluated by the Kaplan-Meier survivorship method and Cox regression analysis. Most acetabular components performed well up to seven years. When the endpoint was revision of the acetabular component because of aseptic loosening, the survival ranged between 87% and 100% at ten years. However, when the endpoint was revision for any reason, the survival estimates were 81% to 92% for the same implants at ten years. Aseptic loosening, wear, osteolysis and dislocation were the main reasons for the relatively poor overall performance of the acetabular components. Prostheses with alumina heads performed slightly better than those with stainless steel or CoCr alloy in subgroups. Whereas most acetabular components performed well at seven years, the survivorship declined with longer follow-up. Fixation was generally good. None of the metal-backed uncemented acetabular components with ultra-high-molecular-weight polyethylene liners in our study had satisfactory long-term results because of high rates of wear, osteolysis, aseptic loosening and dislocation


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_2 | Pages 42 - 42
1 Feb 2020
Ismaily S Parekh J Han S Jones H Noble P
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INTRODUCTION. In theory, Finite Element Analysis (FEA) is an attractive method for elucidating the mechanics of modular implant junctions, including variations in materials, designs, and modes of loading. However, the credence of any computational model can only be established through validation using experimental data. In this study we examine the validity of such a simulation validated by comparing values of interface motion predicted using FEA with values measured during experimental simulation of stair-climbing. MATERIALS and METHODS. Two finite element models (FEM) of a modular implant assembly were created for use in this study, consisting of a 36mm CoCr femoral head attached to a TiAlV rod with a 14/12 trunnion. Two head materials were modelled: CoCr alloy (118,706 10-noded tetrahedral elements), and alumina ceramic (124,710 10-noded tetrahedral elements). The quasi-static coefficients of friction (µ. s. ) of the CoCr-TiAlV and Ceramic-TiAlV interfaces were calculated from uniaxial assembly (2000N) and dis-assembly experiments performed in a mechanical testing machine (Bionix, MTS). Interface displacements during taper assembly and disassembly were measured using digital image correlation (DIC; Dantec Dynamics). The assembly process was also simulated using the computational model with the friction coefficient set to µ. s. and solved using the Siemens Nastran NX 11.0 Solver. The frictional conditions were then varied iteratively to find the value of µ providing the closest estimate to the experimental value of head displacement during assembly. To validate the FEA model, the relative motion between the head and the trunnion was measured during dynamic loading simulating stair-climbing. Each modular junction was assembled in a drop tower apparatus and then cyclically loaded from 230–4300N at 1 Hz for a total of 2,000 cycles. The applied load was oriented at 25° to the trunnion axis in the frontal plane and 10° in the sagittal plane. The displacement of the head relative to the trunnion during cyclic loading was measured by a three-camera digital image correlation (DIC) system. The same loading conditions were simulated using the FEA model using the optimal value of µ derived from the initial head assembly trials. RESULTS. For both head materials, the predicted values of axial displacement of the head on the trunnion closely approximated the measured values derived from DIC measurements, with differences of −0.17% to +6.5%, respectively. Larger differences were calculated for individual components of motion for the stair climbing activity. However, the predicted magnitude of interface motion was still within 10% of the observed values, ranging from −7% to −5%. CONCLUSIONS. Our simulations closely approximated physical testing using complex loading, coming within 7% of the target values. By generating a validated computational model of a modular junctions with varying head materials, we will be able to simulate additional activities of daily living to determine micromotion and areas of peak pressure and contact stresses generated. For any figures or tables, please contact authors directly


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_14 | Pages 40 - 40
1 Nov 2018
Lerf R Delfosse D
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A pin-on-disc tribometer test with a rotating disc and a sector-wise loaded pin was used to determine friction coefficients for different material pairings. The four pin materials porcine cartilage, subchondral bone of the porcine cartilage, UHMWPE, vitamin E enhanced, crosslinked UHMWPE (VEPE) in combination with the three-disc materials zirconia toughened alumina ceramic (ZTA), CoCr, carbon-fibre-reinforced carbon (CrC) were tested. Stepwise loading was employed with the forces 10 N, 5 N, 2 N and 1 N. Test duration was 1 h. Diluted calf serum according ISO 14242-1 was used to determine the friction coefficients. The surface topography of all pins was examined using optical profilometry before and after the rotation tribometer tests. - No wear related modifications of the surface roughness parameters could be found. The coefficients of friction (COF) were lowest for the cartilage pins against all three-disc materials, with steady-state values between 0.01 and 0.02 for the highest applied load (10 N). Friction of subchondral bone yielded COF in the range 0.2 … 0.6, depending on the counterpart material. The two polyethylene materials behaved similar in this friction test with COF of about 0.1. The Ra roughness values of the different pins reflect the COF results: Ra of subchondral bone was one order of magnitude higher than Ra of the cartilage. This is in-line with the COF-values of bone being one order of magnitude higher than those of cartilage. These results will be discussed in view of the use of the disc materials as orthopaedic hemi-prostheses


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXI | Pages 113 - 113
1 May 2012
J. B D. F P. L
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Aim. To study the efficacy of Hydroxyapatite (HAC) Ceramic Coated hip arthroplasty. Is it suitable for the younger patient?. Methods. This series of 2390 primary HAC hip arthroplasties has been studied for up to 21 years. (569 hips over 10 years including 98 hips over 15 years) Patients are assessed by Harris Hip Score and plain X-ray. The prosthesis consists of a fully coated stem and a fully coated acetabulum. A ceramic head articulates with an acetabular liner which is either plastic (UHMW polythene) or ceramic. No cement is used. HA coated implants are physiologically fixed to cancellous bone by a process of osseointegration. Other uncemented implants are pathologically fixed by fibrous scar tissue. These two methods of fixation should be considered separately and not combined as ‘uncemented’. Results. Aseptic loosening in this series is 0.63 %. The revision rate in this series for all reasons is only 3.5%. Harris Hip Score (HHS) demonstrates excellent medium to long term results in 97% of cases (i.e. up to 20 years). Poor HHS results (36 cases: 1.51%) are mostly related to medical or other joint problems. HA fixation will outlast some of the components and wear in polythene acetabular liners can be a problem after 15 years. A sub-group of 629 hips using alumina ceramic/ ceramic bearings is successful but five components fractured (out of 1258 individual components). Wear debris from ceramic materials appears to be benign. Zirconia Toughened Alumina (ZTA) has been introduced to replace alumina and should obviate problems of ceramic implant fracture. An HA coated implant with ZTA bearings is suggested for the younger patient of either sex


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_1 | Pages 55 - 55
1 Jan 2018
Delaunay C
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Since the universal failure of first generation smooth threaded cups in primary total hip arthroplasty (THA), the screw-in concept of cementless acetabular cup fixation has been largely abandoned. We hypothesised that grit-blasted titanium conical cement free threaded cup shows stable long-term fixation. 198 Alloclassic total hip arthroplasties were performed in 179 patients, mean age 66 years old (22–85). 193 hips were analyzed after a mean follow-up of 10 years (1–25 years). Results were excellent or good in 184 hips (95%). Postel-Merle d'Aubigne score increased from 10.3 (range 1 to 15) pre-operatively to 16.7 (12 to 18) points and 151 hips (78%) were pain free at last FU. Radiographic signs indicating successful cup osseointegration were noted in 92% of hips. Polyethylene wear > 0.1mm/year was observed in 6 hips (3%). The main cause of re-operation/revision surgery was recurrent dislocation (9/17cases, 53%). 2 threaded cups were revised for any reason and the revision per cent observed acetabular component years was 0.10 at 10 years average FU. 20 year-survival of the metal back was 98.8% (77.2–99.9%) and 100% (79.6–100%) for revision for any reason and revision for aseptic loosening, respectively. Despite minimum PE thickness of 6.5mm and use of alumina ceramic 28mm heads, conventional polyethylene liner wear was the weak link of the acetabular reconstruction;. This study shows excellent long-lasting bone anchorage through bone on-grown of grit-blasted titanium threaded cup. Despite universal outstanding longevity in the worldwide literature, CSF threaded cups were retrieved from the European market in March 2017 due to insufficient sales, indicating that evidence base medicine may not be the major criteria influencing surgeons' choice


Bone & Joint Open
Vol. 4, Issue 1 | Pages 19 - 26
13 Jan 2023
Nishida K Nasu Y Hashizume K Okita S Nakahara R Saito T Ozaki T Inoue H

Aims

There are concerns regarding complications and longevity of total elbow arthroplasty (TEA) in young patients, and the few previous publications are mainly limited to reports on linked elbow devices. We investigated the clinical outcome of unlinked TEA for patients aged less than 50 years with rheumatoid arthritis (RA).

Methods

We retrospectively reviewed the records of 26 elbows of 21 patients with RA who were aged less than 50 years who underwent primary TEA with an unlinked elbow prosthesis. The mean patient age was 46 years (35 to 49), and the mean follow-up period was 13.6 years (6 to 27). Outcome measures included pain, range of motion, Mayo Elbow Performance Score (MEPS), radiological evaluation for radiolucent line and loosening, complications, and revision surgery with or without implant removal.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 118 - 118
1 Mar 2010
Takakura Y
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The results of total ankle arthroplasty using metal (first generation) and ceramic (second) prostheses were not good for loosening sinking. Then, we have replaced on 159 ankles in 146 cases using beads-formed alumina ceramic prostheses (third) from 1991 to 2006. The follow-up periods were ranged from 2 to 17 years (average 6.5 years). Revision was performed for 13 cases (arthrodesis, 3; re-replacement by artificial talus. 10). Overall satisfactory result of new prostheses for OA was 88%, RA was 74%. Results of OA were better than RA. Furthermore, we have re-replaced using ceramic talar whole body for 10 revision cases. These results until present have been good. It is convinced that total arthroplasty with talar whole body can be indicated for cases with severe deformity and revision


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_3 | Pages 23 - 23
1 Feb 2017
Baek S Nam S Ahn B Kim S
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Background/Purpose. Total hip arthroplasties (THAs) with ceramic bearings are widely performed in young, active patients and thus, long-term outcome in these population is important. Moreover, clinical implication of noise, in which most studies focused on ‘squeaking’, remains controversial and one of concerns unsolved associated with the use of ceramic bearings. However, there is little literature regarding the long-term outcomes after THAs using these contemporary ceramic bearings in young patients. Therefore, we performed a long-term study with a minimum follow-up of . 1. 5 years after THAs using contemporary ceramic bearings in young patients with osteonecrosis of the femoral head (ONFH) less than fifty. Materials and Methods. Among sixty patients (71 hips) with a mean age of 39.1 years, 7 patients (7 hips) died and 4 patients (4 hips) were lost before 15-year follow-up. The remaining 60 hips were included in this study with an average follow-up period of 16.3 years (range, 15 to 18). All patients underwent cementless THA using a prosthesis of identical design and a 28-mm third-generation alumina head by single surgeon. The clinical evaluations included the modified Harris hip score (HHS), history of dislocation and noise around the hip joint: Noise was classified into squeaking, clicking, grinding and popping and evaluated at each follow-up. Snapping was excluded through physical examination or ultrasonography. Radiographic analysis was performed regarding notching on the neck of femoral component, loosening and osteolysis. Ceramic fracture and survivorship free from revision were also evaluated. Results. The mean Harris hip score improved from 55.3 to 95.5 points (range, 83 to 100) at the time of the final follow-up. Seventeen patients (34.7%) reported noise around the hip joint: “squeaking” in one and “clicking” in 16 patients. Notching on the neck of femoral component suggesting impingement between neck and ceramic liner was demonstrated in 9 hips (15%) at average of 6.9 years postoperatively and located at 2 to 3.5 mm distal to edge of ceramic head. Although no chip fracture of ceramic ‘liner’ occurred, notching was associated with “clicking” sound (p<0.01). One patient who reported clicking sound underwent a revision THA because of ceramic ‘head’ fracture. Loosening, osteolysis or dislocation was not observed in any hip and survivorship free from revision at 5 years was 98%. Conclusion. Cementless THAs using 28-mm contemporary alumina ceramic head demonstrated excellent long-term outcome in young, active patients with ONFH. Despite this encouraging result, however, we remain concerned about ‘clicking’ sound, because we did observe it associated with notching on the neck of stem. Acknowledgement. This work was supported by Institute for Information & communications Technology Promotion (IITP) grant funded by the Korea government (MSIP) (#B0101-14-1081)


The Bone & Joint Journal
Vol. 95-B, Issue 8 | Pages 1040 - 1044
1 Aug 2013
Kazi HA Perera JR Gillott E Carroll FA Briggs TWR

We prospectively assessed the efficacy of a ceramic-on-metal (CoM) hip bearing with uncemented acetabular and femoral components in which cobalt­–chrome acetabular liners and alumina ceramic heads were used. The cohort comprised 94 total hip replacements (THRs) in 83 patients (38 women and 45 men) with a mean age of 58 years (42 to 70). Minimum follow-up was two years. All patients had pre- and post-operative assessment using the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), Oxford hip score and Short-Form 12 scores. All showed a statistically significant improvement from three months post-operatively onwards (all p < 0.001). After two years whole blood metal ion levels were measured and chromosomal analysis was performed. The levels of all metal ions were elevated except vanadium. Levels of chromium, cobalt, molybdenum and titanium were significantly higher in patients who underwent bilateral THR compared with those undergoing unilateral THR (p < 0.001). Chromosomal analysis demonstrated both structural and aneuploidy mutations. There were significantly more breaks and losses than in the normal population (p < 0.001). There was no significant difference in chromosomal aberration between those undergoing unilateral and bilateral procedures (all analyses p ≥ 0.62). The use of a CoM THR is effective clinically in the short-term, with no concerns, but the significance of high metal ion levels and chromosomal aberrations in the long-term remains unclear. Cite this article: Bone Joint J 2013;95-B:1040–44


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 110 - 110
1 Jan 2016
Kitamura N Goto K Kondo E Thoyama H Yasuda K
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Introduction. Ceramic total knee arthroplasty (TKA) was introduced as a new-generation of knee prostheses in clinical practice, and are expected to reduce polyethylene wear due to its resistance to abrasion and lubrication. In 1992, we developed a cruciate retaining LFA-I total knee prosthesis (KYOCERA Medical Co., Japan), which comprises an alumina ceramic femoral component and a titanium-alloy tibial component with a polyethylene insert. The purpose of this study was to evaluate clinical results in rheumatoid patients who were treated with the alumina-ceramic LFA-I prosthesis with a minimum 15-year follow-up period. Methods. A total of 70 primary TKAs were performed in 51 patients between 1993 and 1996 using the cemented alumina-ceramic LFA-I prosthesis. Sixteen of these patients (20 knees) had died by the time of this study, of causes unrelated to the index arthroplasty, and 11 patients (16 knees) were lost to the follow-up. The remaining 34 knees were clinically and radiographically evaluated in the present study. The average follow-up time was 16.7 years. The average age of the patients was 58.2 years at the time of the operation. The clinical assessment was conducted with the Hospital for Special Surgery Knee rating score and the Knee Society scoring system. The component alignment and bone-implant interface were evaluated according to the Knee Society Roentgenographic Evaluation System. Results. The cumulative survival rate for revision for any reason at 15 years was 94.1%. The mean postoperative range of motion was 115.3 degrees at the time of the most recent follow-up. The mean postoperative knee score was 90.1 and 84.7 using the Knee Society and the Hospital for Special Surgery rating systems, respectively. Reoperations had been required on two knees due to loosening and on one knee due to infection. Periprosthetic radiolucencies or osteolysis were present in six knees. All lesions occurred around the prosthetic rim; 3 lesions at the anterior femoral flange, 5 lesions at the medial tibia, 2 lesions at the lateral tibia, and 1 lesion at the anterior tibia. These implants did not migrate, subside, or have circumferential radiolucencies that would indicate radiographic loosening. Discussion. In this series of patients with rheumatoid arthritis, the alumina-ceramic LFA-I prosthesis has performed well for the average 16.7 years of follow-up. It is not possible to draw any conclusions regarding the superiority of the ceramic prosthesis with respect to wear and survivability, however, the lack of a ceramic breakage with this anatomical design has encouraged us to continue to use this ceramic prostheses


The Journal of Bone & Joint Surgery British Volume
Vol. 82-B, Issue 7 | Pages 948 - 951
1 Sep 2000
Sychterz CJ Engh CA Young AM Hopper RH Engh CA

At yearly intervals we compared the radiological wear characteristics of 81 alumina ceramic femoral heads with a well-matched group of 43 cobalt-chrome femoral heads. Using a computer-assisted measurement system we assessed two-dimensional penetration of the head into the polyethylene liner. We used linear regression analysis of temporal data of the penetration of the head to calculate the true rates of polyethylene wear for both groups. At a mean of seven years the true rate of wear of the ceramic group was slightly greater (0.09 mm/year, SD 0.07) than that of the cobalt-chrome group (0.07 mm/year, SD 0.04). Despite the numerous theoretical advantages of ceramic over cobalt-chrome femoral heads, the wear performance in vivo of these components was similar


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLI | Pages 143 - 143
1 Sep 2012
Esposito C Roques A Tuke M Walter W Walsh W
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Two types of ceramic materials currently used in total hip replacements are third generation hot isostatic pressed (HIPed) alumina ceramic (commercially known as BIOLOX®forte, CeramTec) and an alumina matrix composite material consisting of 75% alumina, 24% zirconia, and 1% mixed oxides (BIOLOX®delta, CeramTec). The aim of this study is to compare BIOLOX delta femoral heads to BIOLOX forte femoral heads revised within 2 years in vivo. Ceramic bearings revised at one center from 1998 to 2010 were collected (61 bearings). BIOLOX delta heads (n=11) revised between 1–33 months were compared to BIOLOX forte femoral heads with less than 24 months in vivo (n=20). The surface topography of the femoral heads was measured using a chromatically encoded confocal measurement machine (Artificial Hip Profiler, RedLux Ltd.). The median time to revision for BIOLOX delta femoral heads was 12 months, compared to 13 months for BIOLOX forte femoral heads. Sixteen out of 20 BIOLOX forte femoral heads and 6 out of 11 BIOLOX delta femoral heads had edge loading wear. The average volumetric wear rate for BIOLOX forte was 0.96 mm3/yr (median 0.13 mm3/yr), and 0.06 mm3/yr (median 0.01 mm3/yr) for BIOLOX delta (p=0.03). There was no significant difference (p>0.05) in age, gender, time to revision or femoral head diameter between the two groups. Early results suggest less volumetric wear with BIOLOX delta femoral heads in comparison to BIOLOX forte femoral heads


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_3 | Pages 101 - 101
1 Feb 2017
Clarke I Donaldson T Grijalva R Maul C
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Despite 46 years clinical experience with ceramic-on-ceramic (COC) hip bearings, there is no data on what constitutes a successful long-term wear performance. There have been many studies of short-term failures (Dorlot, 1992; Nevelos, 2001, Walters, 2004). One retrieval study using optical-CMM technology (OCM) documented volumetric wear-rates ranging up to 7mm. 3. /year on femoral heads (Esposito 2012). It was noted that 83% of these revisions showed stripe damage within 3–4 years. The supposition would appear to be that these were bearing-related failures. Our selected COC case for this study was particularly interesting, a female patient having her index surgery performed at age 17 and revised at age 49 (following onset of hip pain). This patient led an active lifestyle, went dancing multiple times per week, and was mother to three children. The 38mm Autophor. TM. THA (left hip) was eventually revised due to the cup painful migrating (Fig. 1: 32-years follow-up). Radiographs showed cup inclination at approximately 19. °. Impingement marks were noted on the CoCr neck and collared stem (Fig. 2). Implant geometry and form factors were analyzed by standard contour measurement (CMM) while SEM and EDS imaging provided wear topography and evidence of metal contaminants. Linear and volumetric wear in head and cup were studied by OCM at Redlux (Southampton, UK). The head's main wear-pattern consisted of two overlapping circular areas (Fig. 3). The narrowest margin made by the wear-pattern was used to define the superior aspect of the head. By light microscopy, the superior main-wear zone covered 1490–1680mm. 2. area while the total bi-lobed area covered larger 2170mm. 2. area. OCM analysis delineated the same bi-lobed appearance of head wear with the superior worn area assessed at 1365mm. 2. The cup revealed a more extensive wear pattern that circumnavigated its surface. The black staining identified by EDS imaging in the cup revealed Co and Cr elements. By OCM technique the head volumetric wear was 179 mm³ and the cup was 214mm. 3. (Fig. 4), i.e. 20% greater than head. Volumetric wear-rate averaged 12.3mm. 3. per year for this pioneering alumina ceramic. This first demonstration of long-term, COC volumetric wear provides the foundation for retrieval and simulator studies alike. Our patient represented a “worst-case” scenario for hip-replacement surgery, due to extreme youth and long-term sporting life. While the superior wear pattern was not totally contained within the cup (Fig. 3), her implant positioning was clearly adequate. Nevertheless both cup edge-wear and CoCr contamination indicated this patient experienced habitual impingement, i.e. alumina cup rim wearing against CoCr femoral neck (Fig. 2). The head wear-pattern was distinctly bi-lobed but OCM images showed the majority of wear was in the superior hemisphere as noted in MOM retrievals (Clarke, 2013). The head wear-rate in this pioneering “Mittelmeier” THA averaged 5.6mm³/year over 32-years of follow-up. This appeared directly comparable to ceramic head wear measured with the same OCM-technique in modern ceramic THA (Esposito, 2012: 0.1 to 7mm. 3. /year). This indicated to us that COC wear rates of the order 10–14mm. 3. /year represented an acceptable “normal” level of performance in young and active individuals


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 1 - 1
1 Jan 2016
Giardina F Guerra G Stea S Bordini B Sudanese A Toni A
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After a few years from its introduction, the limits of the THA became evident, mainly due to high rates of mobilization for polyethylene wear and to the release of metal ions from MOM and MOP couplings. Ceramic bearings were thus introduced in surgery to obtain lower levels of friction and wear. These issues have now been well recognized by several studies, which show that ceramic-on-ceramic joint has the lowest wear rate among various articulations and that ceramic particles induce less macrophage reaction and decrease cytokine secretion, allowing to have little periprosthetic osteolysis. After the first results in the late 70′s and early 80′s, the mechanical reliability was improved due to the manufacturers' efforts to reduce the ceramic fragility evolving average grain microstructure and lowering the degree of impurity. Betterment and standardization of production have led to 3. rd. generation alumina, Biolox Forte in 1994, that achieved a lower incidence of fracture. The purpose of our study has been to assess long-term follow-up results of alumina-on-alumina 3. rd. generation ceramic total hip cementless arthroplasty performed at our institution from January 1995 to December 2000. We prospectively followed more than 200 patients operated of THA for primary or secondary hip osteoarthritis analyzing clinical and radiographs features. In this period, the total hip replacement were performed by a single surgeon, who is the senior author (A.T.) in our Institution. All patients were clinically examined to confirm the diagnosis and all of them were checked with a standard plain radiographs in two projections and, when necessary, the radiographic examination was completed by CT scans. The same prosthesis was used in all patients, a 3. rd. generation alumina COC articulation, composed of a hemispherical titanium alloy cup and a 28-mm alumina ceramic femoral head. The modular ceramic head was fixed to a 12/14 taper cone. Proximally plasma-spray hydroxyapatite coated Ti alloy stems completes the implant features. Modular necks were used in retro or anteversion and varus or valgus offset, allowing changes in neck-shaft angle and giving a perfect intraoperative stability. Clinical assessment was performed using the Merle-D'Aubigne and Postel hip score. Each patient was assessed before surgery, after 30 days, afterwards at 4 months and annually after surgery. The mode of femoral component fixation was radiographically classified as bone ingrowth fixation, stable fibrous fixation or unstable fixation, according to the criteria Engh-Bobyn. Osteolysis was evaluated on the femoral side at each Gruen zone. Osteolysis on the acetabular side was evaluated by DeLee and Chanley zone. Our study has concluded that cementless modular hip arthroplasty with 3. rd. generation ceramic-on-ceramic bearing, with a 13 to 18 years follow-up, shows an excellent survivorship, in particular for the very low volume release of microparticles during friction, which consequently reduction of cytokine release, thus diminishing the risk of periprosthetic osteolysis and loosening of implant components


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 94 - 94
1 Jan 2016
Yamane S Kawahara I Oonishi H Iwamoto M Kyomoto M Hanaoka Y Oonishi H
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In total hip arthroplasty (THA), aseptic loosening induced by polyethylene (PE) wear debris is the most important cause that limits the longevity of implants. Abrasive wear generated through the mechanism such that micrometer-roughened regions and small asperities on the metallic femoral heads surface locally plow through the PE cup surface. Abrasive wear results in the PE material being removed from the track traced by the asperity during the motion of the metallic femoral heads surface. For the purpose of reducing wear, alumina ceramics was introduced in Europe and Japan in 1970s. The clinical results of ceramic-on-PE bearings regarding the wear resistance have been superior to that of the metal-on-PE bearings. Compared with Co–Cr–Mo alloys, alumina ceramics is advantageous for precision machining because of its higher hardness, enable to form spherical and smooth surface. The fracture resistance of the alumina ceramics itself is related to grain size; the grain size reduction leads to the improvement of its resistance. In this study, we evaluated the roundness and the roughness of retrieved two distinct alumina ceramics having different grain size, and Co–Cr–Mo alloy heads. Fourteen retrieved alumina ceramic femoral heads; ten heads with a diameter of 28 mm made of small grain size alumina (SG-alumina; mean grain size is 3.4 μm) with clinical use for 16–28 years and four heads with a diameter of 26 mm made of extra-small grain size alumina (XSG-alumina; mean grain size is 1.3 μm) with clinical use for 14–19 years, were examined. Six retrieved Co–Cr–Mo alloy femoral heads with a diameter of from 22 to 32 mm with average clinical use for 12–28 years were examined. SG-alumina and XSG-alumina heads showed significantly lower roundness compared with Co–Cr–Mo alloy heads, due to higher precision machining [Fig. 1]. The surface roughness for the contact area of the heads increased in order of XSG-alumina, SG-alumina and Co–Cr–Mo alloy. The surface roughness of the non-contact area for all kinds of heads was lower than that for the contact area [Fig. 2]. Surface profiles of the SG-alumina and XSG-alumina showed the reentrant surface while Co–Cr–Mo alloy heads showed the protrusion surface. The roundness and roughness of the Co–Cr–Mo alloy or ceramic surface and the presence or absence of hard third-body particles correlate to the amount of abrasive PE wear. When the third-body was entrapped during the clinical use, a reentrant surface might be formed on the ceramic while protrusion surface formed on the Co–Cr–Mo alloy. The differences in clinical results may be due in part to the influence of third-body particles. The ceramic becomes more resistant than Co–Cr–Mo alloy against the scratching by the entrapped abrasive contaminants because of its harder surface. From the good clinical results of more than 20 years using SG-alumina, the greater long term clinical results using XSG-alumina will be expected


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 114 - 114
1 Jan 2016
Thornton-Bott P Tai S Walter W Walter W Zicat B
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Introduction and Aims. The 21. st. Century has seen ceramic bearings become an increasingly popular choice in total hip arthroplasty due to their high wear resistance and inert wear debris without osteolysis promising a long term bearing solution. Early ceramic bearings were hindered by fracture but improved manufacturing processes and materials subsequently produced stronger ceramics. These third generation ceramics showed greatly reduced fracture rates but there is limited evidence in the literature reporting their long term survival and wear characteristics. The purpose of this study was to determine osteolysis and survival rates of Alumina ceramic bearings in cementless total hip arthroplasties with a minimum follow-up of 15 years. Methods. We analyzed a series of 301 third-generation alumina-on-alumina cementless primary total hip replacements in 283 patients. The average age of the patients at the time of the arthroplasty was fifty-eight years, 51% were in women and 54% were right sided. All procedures were performed using the same surgical technique and the same implant at a single centre. Patients were followed up at six weeks, one, two, five, ten and 15 years. At 15 years postoperatively 46 patients (17%) had died of unrelated causes and 31 (10.2%) were lost to follow-up. Patients were assessed clinically and radiographically. Retrieved bearings were analyzed for wear. Results. At the time of the latest follow-up the mean Harris Hip Score was 94 points and 97% of the patients scored an excellent or good result with less than 4% having moderate residual pain. Radiographically, all patients assessed had evidence of stable bony ingrowth. Minor osteolysis was seen adjacent to 4% of cups and in none of the stems. There were eleven revisions in all, four stem revisions due to periprosthetic fracture, one secondary to aseptic loosening and one to facilitate a femoral shortening osteotomy. One cup was revised for aseptic loosening and one cup was revised for soft tissue impingement. One cup underwent revision due to acetabular osteolysis due to metallosis with some ceramic wear caused by neck impingement. There were two revisions for ceramic fracture, one liner and one femoral head. Overall, the survival rate of the implants for any cause revision was 96% at 15 years, with. The rate of survival of both components, with revision because of aseptic loosening or osteolysis as the end point, was 99% at 15 years. Analysis of retrieved femoral heads identified a median wear rate of 0.2mm3/year. Conclusion. Ceramic bearings were designed to overcome the problem of osteolysis due to wear from polyethylene bearings. This study has shown that Alumina bearings in cementless primary total hip arthroplasty have an excellent survival rate at 15 years with good function, low wear rate and no adverse radiographic changes typical of osteolysis. The fracture rate was low in our study. These findings strongly supporting the use of Ceramic as a bearing choice for the 21. st. Century


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_7 | Pages 87 - 87
1 May 2016
Clarke I Burgett-Moreno M Bone M Scholes S Joyce T Donaldson T
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Metal-on-metal retrieval studies indicated that MOM wear-rates could rise as high as 60–70mm3/year in short-term failures (Morlock, 2008). In contrast, some MOM and ceramic-on-ceramic (COC) devices of 1970's era performed admirably over 2–3 decades (Schmalzreid, 1996; Shishido, 2003). While technology has aided analysis of short-term MOM and COC failures (Morlock 2008; Lord 2011), information on successful THA remains scant. Lack of long-term data creates difficulties in setting benchmarks for simulator studies and establishing guidelines for use in standards. In this study we compared clinical and wear histories for a 30-year MOM and a 32-year COC to establish such long-term, wear-rates. The McKeeTM retrieval was cemented and made 100% of CoCr alloy (Fig. 1a). This patient had a right femoral fracture at 47 years of age, treated by internal-fixation, which failed. Her revision with a Judet implant also failed, leaving her right hip as a Girdlestone. At the age of 68, she had a McKee THA implanted in left hip, and used it until almost 98 years of age (Campbell, 2003). The COC case was a press-fit AutophorTM THA, head and cup made of alumina ceramic, with the only metal being the CoCr stem (Fig. 1c). This was implanted in a female patient 17-years of age active in sports (water-skiing). This modular THA was revised 32-years later due to hip pain from cup migration. Wear on these implants was identified by stereomicroscopy and stained red for photography (Fig. 1). Cup-to-neck impingement was denoted by circumferential neck notching, roughness was assessed by interferometry, and wear determined by CMM (Lord, 2011). McKee head wear covered 1092mm2 area (Figs. 1a, 2: hemi-area ratio 58%). There was no stripe wear and head roughness was 36nm (Ra). Cup wear covered an area of 1790mm2 (hemi-area 63%). Circumferential damage was noted on the supero-posterior femoral neck with scuff marks also on posterior collar (Fig. 2c). Head and cup wear amounted to 37.7 and 25.2mm3, respectively. Total MOM wear was 62.9mm3, indicating a wear-rate of 2.1mm3/year. Ceramic head wear consisted of two circular patterns (Fig. 1c), the major one of area 1790mm2 (hemi-area 79%). No wear stripes were identified. Non-worn and extensively worn surfaces had roughness (Ra) 17nm and 123nm, respectively. The cup showed 360o circumferential arc of rim wear with a small, non-wear zone inferiorly (Fig. 1c). Gray metallic transfer was evident, EDS revealing Co and Cr (Fig. 3a). Head and cup wear volumes were 77.2 and 54mm3, respectively. Total COC wear amounted to 131.2mm3 indicating a wear-rate of 4.1mm3/year. These two THA functioned successfully over 3 decades. The McKee retrieval had minor signs of impingement but no adverse “stripe wear”. This MOM performed satisfactorily due to good positioning and patient's advanced age (68 to 98Yrs of age). The COC patient was 17 years of age at index surgery and active. The ceramic cup showed 360o of edge wear, CoCr transfer and a COC wear-rate double that of the MOM retrieval. Thus the high ceramic wear-resistance protected this youthful patient


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 262 - 262
1 Sep 2012
Buchanan J Fletcher R Linsley P
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Aims. Will Hydroxyapatite hip (HA) arthroplasty associated with ceramic bearings produce uncomplicated function in younger, active patients’ The incidence of aseptic loosening, dislocation and broken implants has been particularly investigated. Debris disease from plastic debris contributes to aseptic loosening. Hard-Hard bearings should obviate this problem. Metal-metal will release ions which might be deleterious. Experience with metal-metal resurfacing has high lighted problems including pseudo-tumours. Ceramic bearings may fracture but otherwise appear free of complications. Methods. This is a study extending over 19 years of 626 HA hip arthroplasties with ceramic bearings. Annual review using Harris Hip Score to assess pain and function and X-rays to check osseointegration has been performed. Alumina ceramic was inserted in 467 hips. The newer Zirconia Toughened Alumina (ZTA) has been inserted in 169 hips. There are 118 hips still under review at 10 or more years. Results. Aseptic loosening is unusual (one stem, two acetabulae (3 of 1252 components, 0.24%) Failure from mal-orientation with repeated dislocation occurred in six hips (0.96%). Three alumina heads (0.48%) and two alumina liners (0.32%) broke. There has been no failure of ZTA ceramic. No patients have thigh pain. Osteolysis and debris disease have not arisen. Harris Hip Scores show 91.2% scoring over 90 or 100. Lower scores mostly relate to other joint and medical problems. Conclusions. Assessments confirm that patients remain well. Aseptic loosening of HA hips is rare at 0.24%. Failure from broken alumina components is unusual. Alumina has now been superseded by ZTA for implantation. Ceramic on ceramic is a reliable selection for bearing surfaces in patients of any age and either sex


The Journal of Bone & Joint Surgery British Volume
Vol. 84-B, Issue 6 | Pages 839 - 845
1 Aug 2002
Havelin LI Espehaug B Engesæter LB

We have compared the survival of two hydroxyapatite (HA)-coated cups, 1208 Atoll hemispheric and 2641 Tropic threaded, with cemented Charnley all-polyethylene cups (16 021) using the Cox regression model. The Tropic cup used in combination with an alumina ceramic femoral head, had good results, similar to those of the Charnley cup. When used in combination with a stainless-steel head, however, the risk of revision beyond four years was increased 3.4 times for the Tropic cup compared with the Charnley cup (p < 0.001). Over the same period, the Atoll cup had an increased risk of revision of 3.8 times when used with the alumina heads (p < 0.001) and an increased risk of 6.1 times when used with stainless-steel heads (p < 0.001). Revision because of wear and osteolysis was more common with both types of HA-coated cup than with the Charnley cup. The rate of revision of the Atoll cup because of aseptic loosening was also increased. We found that HA-coated cups did not perform better than the Charnley cup


The Journal of Bone & Joint Surgery British Volume
Vol. 80-B, Issue 5 | Pages 894 - 899
1 Sep 1998
Minakawa H Stone MH Wroblewski BM Lancaster JG Ingham E Fisher J

We examined stainless-steel, cobalt-chrome, titanium and alumina and zirconia ceramic femoral heads retrieved at revision surgery. All the heads had articulated against ultra-high-molecular-weight-polyethylene (UHMWPE) acetabular cups. We studied the simulation of third-body damage and the wear of UHMWPE against the various materials used for the heads. The surfaces of the retrieved heads were analysed using a two-dimensional contacting profilometer. Third-body damage was characterised by the mean height of the scratches above the mean line (R. pm. ). The alumina ceramic and zirconia ceramic retrieved heads were found to have significantly less damage. In laboratory studies the ceramics were also more resistant to simulated third-body damage than the metal alloys. We studied the wear of UHMWPE against the damaged counterfaces in simple configuration tests. The damaged ceramics produced less polyethylene wear than the damaged metal counterfaces. The wear factor of UHMWPE against the damaged materials was dependent on the amount of damage to the counterface (R. p. ). Our study has shown the benefit of using the harder and more damage-resistant ceramic materials for femoral heads


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 170 - 170
1 Mar 2013
Esposito C Roques A Tuke M Walsh WK Walter WL
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Introduction. Two types of ceramic materials currently used in total hip replacements are third generation hot isostatic pressed (HIPed) alumina ceramic (commercially known as BIOLOX®forte, CeramTec) and fourth generation alumina matrix composite ceramic consisting of 75% alumina, 24% zirconia, and 1% mixed oxides (BIOLOX®delta, CeramTec). Delta ceramic hip components are being used worldwide, but very few studies have analyzed retrieved delta bearings. The aim of this study is to compare edge loading ‘stripe’ wear on retrieved femoral heads from delta-on-delta, delta-on-forte and forte-on-forte ceramic bearings revised within 2 years in vivo. Material and Methods. Ceramic bearings revised at one center from 1998 to 2010 were collected (61 bearings). Eleven delta heads revised between 1–33 months were compared to 24 forte femoral heads with less than 24 months in vivo (Figure 1). The surface topography of the femoral heads was measured using a RedLux AHP (Artificial Hip Profiler, RedLux Ltd, Southampton, UK). Three representative samples were examined with a FEI Quanta 200 Scanning Electron Microscope (SEM). Results. The median time to revision for delta femoral heads was 12 months, compared to 13 months for forte femoral heads. Sixteen out of 20 forte femoral heads and 6 out of 11 delta femoral heads had edge loading wear (Figure 2). The average volumetric wear rate for forte was 0.96 mm. 3. /yr (median 0.13 mm. 3. /yr), and 0.06 mm. 3. /yr (median 0.01 mm. 3. /yr) for delta (p=0.03). There was no significant difference (p>0.05) in age, gender, time to revision or femoral head diameter between the two groups. Conclusions. Edge loading wear occurs in BIOLOX®delta ceramic bearings. Edge loading wear volumes and wear rates are less in these bearings compared to BIOLOX®forte bearings. These findings are consistent with hip simulator studies. Early analysis of retrieved implants is important to check the in vivo performance of biomaterials


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 18 - 18
1 Jan 2004
Yasuda K Majima T Aoki Y Minami A Tohyama H
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The aim of the study was to compare clinical results after cruciate-retaining total knee arthroplasty (TKA) between the ceramic and the Co-Cr alloy condylar prostheses. In a prospective semi-randomised study, 218 patients underwent cruciate-retaining TKA with the Co-Cr alloy prosthesis (Kinemax®, Howmedica) or the LFA-I® prosthesis (Kyocera) composed of an alumina ceramic femoral component and a titaniumalloy tibial component with a UHMWPE insert. In each surgery, both components were fixed with PMMA cement. All the patients underwent the same postoperative management. Finally, 110 knees with the ceramic prosthesis and 84 knees with the Co-Cr prosthesis were followed up for 24 to 124 months (the average of 56 months). Two revisions were performed in each group (tibial tray breakage and infection in the ceramic group, and loosening and infection in the Co-Cr group). In the remaining patients, there were no significant differences in the HSS knee score (85 and 86 points, respectively) and the ROM (112 and 113 degrees) between the two groups. In radiological evaluation, a radiolucent line was more frequently observed with the significance (p< 0.05) in the Co-Cr alloy group (9.5 %) than in the ceramic group (2.7 %). In the mid-term follow-up evaluations, the clinical results of the ceramic TKA are equivalent to those of the Co-Cr alloy TKA. In addition, the ceramic prosthesis showed some statistical tendency of superiority to the Co-Cr prosthesis concerning the radiolucent line. These results encouraged us to conduct a long-term follow-up study on the ceramic total knee prosthesis


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 6 - 6
1 Jan 2004
Kim S Oonishi H Fujita H Ito S
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We have used Interface Bioactive Bone Cement (IBBC) in all cases of total joint arthroplasties since 1987. The method is improved cement technique by interposing less than two layers of hydroxyapatite (HA) granules between bone and the polymethylmethacrylate (PMMA) bone cement. We report one patient who underwent revision surgery after total knee arthroplasty (TKA) using IBBC. The patient is a woman aged 70 years at the time of revision surgery. Right TKA was performed with the diagnosis of rheumatoid arthritis. An alumina ceramic total knee prosthesis was inserted using IBBC. Pain and walking ability were once improved after the primary TKA. However, the gait disturbance recurred after the patient fell on the ground. Radiographic findings showed severe genu varum, but neither radiolucent lines around the components nor migration of the components were seen. This was revised with semiconstrained prosthesis for the purpose of improving lateral instability at 31 months after the primary TKA. Avulsion of fibular attachment of collateral ligament was seen at the time of the revision surgery. As PMMA cement was strongly adhered to the bone, it was removed together with cancellous bone. Histologically, HA granules bound to the bone directly after bone ingrowth into the spaces around the HA granules. This is the reason we have described IBBC as a method having the both advantages of cementless HA coating and PMMA bone cement. After the revision surgery, the walking ability was improved. In conclusion, this case showed excellent characteristics of IBBC


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIII | Pages 30 - 30
1 May 2012
Kosugi S Tanka Y Yamaguchi S Taniguchi A Shinohara Y Matsuda T Kumai T Takakura Y
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Introduction and aims. Recently many implants for ankle arthroplasty have been developed around the world, and especially some mobile bearing, three-component implants have good results. Nevertheless, at our institution fixed two-component, semi-constrained alumina ceramic total ankle arthroplasty (TAA) with TNK Ankle had been performed since 1991 and led to improved outcomes. We report clinical results and in vivo kinematic analyses for TNK Ankle. Method. Between 1991 and 2006, total ankle arthroplasties with TNK Ankle were performed with 102 patients (106 ankles) with osteoarthritis at our institution. There were 91 women and 11 men. The mean age was 69 years and mean follow-up was 5.4 years. These cases were evaluated clinically and radiographically. Besides in vivo kinematics, in TNK Ankle was analysed using 3D-2D model registration technique with fluoroscopic images. Between 2007 and 2008, prospectively ten TAA cases examined with fluoroscopy at postoperative one year. Results. In clinical results, excellent were 48 cases, good were 31 cases, fair were 10 cases, poor were nine cases, and death and loss to follow-up were 10 cases. Reoperations are performed on eight cases, one was arthrodesis, seven were talar component revision or talar revision with ceramic whole talus prosthesis. TNK Ankle have the rough surfaces by beadworks, and added surface treatment with hydroxyapatite granules, calcium phosphate paste or tissue engineered mesenchymal cells. Recently, only talar components were fixed with bone cement. Loosening has been more frequent in talar than tibial, whereas no reoperation was on cemented talar component cases. According to 3D-2D model registration, both components rotated a little each other and the contact region between both components variously sifted during weight bearing flexion of ankle. It was supposed that replaced position and angle of components concerned with the contact region. Conclusions. TAA with TNK Ankle have led to better results with improvement for surface treatments. Kinematics of ankle prostheses was derived by 3D-2D model registration, more appropriate position and angle to replace


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 88 - 88
1 Mar 2010
KIM Y YOO JJ YOON KS KOO K LEE Y KWON YS KIM HJ
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Background: Ceramic-on-ceramic couplings are an attractive alternative bearing surfaces to eliminate or reduce problems related to polyethylene wear debris. Past disappointing experiences with alumina ceramic bearings have led to many improvements in the manufacture and the design of ceramic implants. The purpose of this study was to report the results of contemporary alumina-on-alumina total hip arthroplasties (THAs) with regard to wear, osteolysis, and fracture of the ceramic after a 10-year minimum follow-up. Methods: We evaluated the results of a series of 66 primary alumina-on-alumina THAs with a metal-backed socket and a cementless stem in 59 patients. All of the patients were 64 years old or younger (mean, 42 years), and a single surgeon performed all of the procedures. They were evaluated clinically and radiographically at the 120 to 126 months follow-up (average, 123 months). During the follow-up, special regards were addressed to wear, periprosthetic osteolysis and ceramic failure. Results: During the follow-up period, two patients (two hips) had died with the prosthesis in situ as the result of an unrelated medical condition. The mean Harris hip score was 94 points at the latest follow-up evaluation. All of the prostheses had radiographic evidence of a bone ingrowth. No implant was loosened radiographically and no implant was revised. Ceramic wear was not detectable in the 28 hips where differentiation of the femoral head from the cup was possible on radiographs. Periprosthetic osteolysis was observed in no hip. A fracture of the alumina femoral head and a peripheral chip fracture of the alumina insert occurred in one hip following a major motor vehicle accident. A periprosthetic femoral fracture, which required open reduction and internal fixation with metal cables, had occurred in one hip. This fracture healed without problem. Conclusion: The results of contemporary alumina-on-alumina THAs with a metal-backed socket and a cementless stem were encouraging after a minimum follow up of 10 years. We believe that these improved alumina-on-alumina bearing implants offer a promising option for younger active patients


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 7 | Pages 928 - 933
1 Jul 2005
Berli BJ Schäfer D Morscher EW

The Morscher-Spotorno (MS-30) femoral stem is a stainless-steel, straight, three-dimensionally tapered, collarless implant for cemented fixation in total hip replacement. We report the results at ten years of a consecutive series of 124 total hip replacements in 121 patients with the matt-surfaced MS-30 stem and an alumina ceramic head of 28-mm diameter. All the stems were fixed with Palacos bone cement with gentamicin using a modern cementing technique. They were combined with an uncemented, press-fit cup. The mean period of observation was 10.2 years (8.3 to 12.1) and no patient was lost to follow-up. Twenty-seven patients (22%) died with the implant in situ. Nine could only be interviewed by telephone. We included 85 patients with 88 hips in the clinical and radiological follow-up examinations. None of the stems or cups had been revised. The Harris hip score was excellent or good in 97% (85 hips) and moderate in 3% (three hips). Radiologically, six hips (6.8%) had osteolysis adjacent to the stem, mostly in Gruen zone 7. Twenty (22.7%) showed one or more radiolucent lines. Twenty-two stems (25%) had subsided by 2 mm to 5 mm. In these cases two showed osteolysis (9.1%) with subsidence and four without (6.1%). Radiolucent lines were seen in seven with migration (31.8%) and in 13 without (19.7%). No infections and no acetabular osteolysis were observed. The clinical results were excellent with survivorship after ten years of 100% and only a slightly statistically non-significant higher rate of osteolysis and radiolucency in cases of subsidence


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_III | Pages 361 - 361
1 Mar 2004
Capello WN DñAntonio JA Bonutti P Manley MT
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Aims: To compare acetabular surface treatments in alumina on alumina clinical trial. Methods: Utilizing new improved alumina ceramic materials and implant design, 514 hips were implanted in a US IDE prospective randomized study. All patients received the same press-þt hydroxylapatite-coated (HA) femoral stem. Two-thirds (349 hips) received an alumina ceramic bearing surface, while one-third (165 hips) received a cobalt chrome on polyethylene bearing. The alumina group was further divided with approximately one-half receiving a porous-coated titanium shell and alumina insert (172 hips Ð System I), and one-half receiving an arc deposited titanium shell with HA coating and alumina insert (177 hips Ð System II). System III, the control group, had a porous-coated titanium shell and polyethylene insert. All acetabular shells were of identical external geometry. Results: At latest follow-up, minimum 2 years (2–4 year range), differences were noted in the pattern of development of radiolucent lines around the acetabular components. Radiolucent lines were noted most commonly in De Lee Charnley Zone 3 in porous-coated shells (25/164 hips Ð System I, 33/151 hips Ð System III respectively). Radiolucent lines in Zone 3 were absent in the arc deposited with HA shells (System II) (p=0.001). Conclusions: These results appear to demonstrate that PSL style cups with arc dep and HA coating may improve levels of primary þxation versus that of porous-coated acetabular components


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 21
1 Mar 2002
Villermaux F
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Ceramic-ceramic (C-C) bearings have 20 years clinical experience with alumina ceramics. This system is re-emerging because of its demonstrated excellent wear performance compared to metal-PE or ceramic-PE. However, alumina ceramic imposes a design limitation to reduce breakage risk: most of the implanted C-C systems present a head larger than 28 mm. Zirconia ceramic is three-times more mechanically resistant and has proven its efficiency in ceramic-PE couple. As a result, a new C-C bearing with zirconia head has been studied. Excellent wear performance of the zirconia-alumina (Z-A) combination system has already widely been proven through multilaboratory experiments on a hip simulator. The mechanical aspect is investigated here to analyse the benefit of a zirconia head in a C-C system. This aspect has been first studied by Finite Element Analysis (FEA) and then validated by experimental testing. The first series of tests on the 28mm system confirmed the FEA predictions: the breakage loads were correctly estimated for each assembly, showing that FEA is an effective tool to predict breakage load and location. The second series of tests were performed on 22.22mm systems. FEA predicted that the Z-A system should pass the 46 kN contrary to the A-A system. Breakage of the A-A system is expected to be in the head. In conclusion, Z-A combination offers higher mechanical security for the existing C-C designs but above all, larger design choice than A-A system. Considering that wear performances are equivalent, the Z-A system can be thought as the logical evolution of A-A system


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 415 - 415
1 Nov 2011
Park Y Moon Y Lim S Kim J
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As the proximal femoral bone is generally compromised in failed hip arthroplasty, achievement of solid fixation with a new component can be technically demanding. Recent studies have demonstrated good short-term clinical results after revision total hip arthroplasty using modular distal fixation stems, but, to our knowledge, none have included clinical follow-up of greater than 5 years. The purpose of this study was to report the clinical and radiographic outcomes assessed 5 to 10 years following revision total hip arthroplasty with a modular tapered distal fixation stem. We retrospectively evaluated 50 revision total hip arthroplasties performed using a modular tapered distal fixation stem Between December 1998 and November 2003. There were 15 men (16 hips) and 34 women (34 hips) with a mean age of 59 years (range, 36 to 80 years). The index operation was the first femoral revision for 46 hips, the second for 3 hips, and the fifth for 1 hip. According to the Paprosky classification, 5 femoral defects were Type II, 31 were Type IIIA, and 14 were Type IIIB. An extended trochanteric osteotomy was carried out in 24 (48%) of the 50 hips. Patients were followed both clinically and radiographically for a mean of 7.2 years. The mean Harris hip score improved from 54 points preoperatively to 94 points at the time of the latest follow-up. The mean stem subsidence was 1.5mm. Three stems subsided more than 5 mm, but all have stabilized in their new positions. During follow-up, a total of 4 hips required additional surgery. One hip had two-stage re-revision due to deep infection, one had liner and head exchange for alumina ceramic head fracture, and the other two underwent isolated cup re-revision because of aseptic cup loosening and recurrent dislocation, respectively. No repeat revision was performed due to aseptic loosening of the femoral component. Complications included 6% intraoperative fractures, 4% cortical perforations, and 4% dislocations. There were no stem fractures at the modular junction. The medium-term clinical results and mechanical stability obtained with this modular tapered distal fixation stem were excellent in these challenging revision situations with femoral bone defects


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_III | Pages 253 - 253
1 Jul 2011
Lewis P Al-Belooshi A Olsen M Schemitsch EH Waddell JP
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Purpose: The use of UHMW polyethylene acetabular liners is known to cause polyethylene wear related osteolysis, the major limiting factor in its use in the younger active patient. Modern alumina ceramic articulations have been developed in order to reduce wear and avoid polyethylene debris. This prospective randomized long-term study aims to compare the outcome between an alumina ceramic-on-ceramic (CC) articulation with a ceramic on UHMW polyethylene articulation (CP). Method: Fixty-six hips in 55 patients with mean age 42.2 (range 19–56) each received uncemented components (Wright Medical) and a 28mm alumina head with acetabular liner selected via sealed envelope randomization following anesthetic induction. Subsequent regular clinical and radiologic follow up measured patient outcome scores and noted any radiological changes. Results: Twenty-six CP hips and 30 CC hips were evaluated. One failure required revision in each group. Mean St Michael’s outcome score for each group with up to 10 years follow-up (median 8 years, range 1–10) was 22.8 and 22.9 respectively (p=0.057). Radiographs with a minimum 5 years post-operative follow-up were analyzed in 42 hips (23 CC and 19 CP). The mean time of wear measurement for the CC group was 8.3 years (SD 1.3, Range 4.8–10.1 years) and for the CP group was 8.1 years (SD 0.9, Range 6.1–9.2 years)(p=0.471). Wear was identified in all but one CP hip but in only 12 of 23 CC replacements. Mean wear in the CP group was 0.11mm per year and 0.02mm per year in the CC group (p< 0.001). Conclusion: To our knowledge this is the first long term randomized trial comparing in-vivo ceramic-on-ceramic with ceramic-on-polyethylene hip articulations. Other than significantly greater wear in the polyethylene group there was no significant difference in long-term outcome scores between the two groups with up to 10 years of follow-up. The use of a ceramic-on-ceramic bearing is a safe and durable option in the young patient avoiding the concerns of active metal ions and osteolytic polyethylene debris


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 132 - 132
1 Mar 2010
Tsukamoto R Clarke I Williams P Donaldson T Tsukamoto M Tsuji K Matsuda Y Tatsumi I Hirakawa K
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Suggestions for improved wear performance of total knee replacements have included replacement of standard CoCr femoral components with ceramic. Yttria-stabilized zirconia (y-TZP) was introduced as high-strength and high toughness ceramic as an alternative to alumina ceramic. Since the introduction of zirconia in 1985, the clinical outcomes and successes for hip joint have been controversial. Y-TZP ceramics have been studied both experimentally and clinically. Magnesia-stabilized zirconia (Mg-PSZ) also appears promising for total knee replacements (TKR). Mg-ZrO2 and CoCr femoral condyles were compared in the VanguardTM knee configuration (Biomet Inc, IN). Molded tibial inserts (GUR1050) were gamma-irradiation sterilization to 3.2-Mrad under argon. Knee simulation was conducted on a 6 station simulator (Shore Western Manufacturing, Monrovia, CA). Motion included 20 degrees of flexion/extension, 5 degrees of internal/external rotation and 5 mm of AP-translation. All knee components were subjected to 6 million cycles of normal walking (2.9 kN max, freq 1.4 Hz). Lubricant was 50% alfa-calf serum diluted to 20 mg/ml protein and using EDTA additive. Test duration was 6 million cycles (6-Mc), and wear was measured by weight-loss techniques. For wear trending of CoCr/PE and MGZ/PE, linear wear trends were apparent from 1 to 6 Mc test duration. The control implants (CoCr/PE) showed excellent linear trending (regression coeff r> 0.99) with wears rate averaging 6.3 mm3/Mc. These data showed good control of experimental variance (< 10%). The ZrO2/PE combination showed good linear trending (r > 0.86) with wear rate averaging only 0.8 mm3/Mc. This set also showed good control of experimental variance (< 15%. The MGZ/PE wear was 8-fold reduced from that of CoCr/PE. The laboratory knee wear simulation appeared very supportive of femoral condyles of Mg-stabilized zirconia. Such implants may provide excellent performance for active patients who may risk high wear rates over many years of use


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 188 - 188
1 Mar 2008
Variola F Pezzotti G Gaspera OD Falcone G De Santis V agliocchetti G Sakakura S Clarke I
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Alumina ceramic has been used in total hip arthoplasty since the 70’s and, in the last 30 years, a considerable evolution has occurred in designing the microstructural features of this material, taking advantage of improved processing techniques, as the hot isostatic pressing. As a result, a high degree of densification (> 99.5) has been achieved in materials with a high degree of purity and, especially, with a fine grain size ( 2 microns). The surface stress field acting on a femoral head inoperation is not only due to working conditions, but also to unexpected factors, as local impacts on the surface as a result of partial dislocations, formation of debris, etc. These additional factors greatly contribute to activate degradation mechanisms which, unfortunately, may lead to failure of the implant. In this study, five alumina femoral heads were investigated, which were retrieved from patients after different periods of time. Among those investigated femoral heads, two belonged to a first-generation type of alumina material with a relatively coarse grainsize (average value 8 microns) and were retrieved due to surface degradation after long periods of implantation (19 and 17 years, respectively); the remaining three implants analyzed were instead recently manufactured implants with a fine grain size; they were retrieved after relatively short periods because of different causes as, for example, cup or stem loosening. Surface stress analysis using the luminescence of Cr3+impurity in alumina was performed on the retrieved femoral heads and a statistical comparison was attempted among implants with different microstructural characteristics. The investigation led to estimate average residual stress and statistical stress distributions as a function of the location on the femoral head. The analysis was performed both on the very surface and in the sub-surface of the head, using the confocal and the through-focus configurations of the optical spectrometer, respectively. Different statistical distributions of residual stress were observed in alumina femoral heads with different grain sizes and models were created to understand their dependence on processing and surface loading


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 83 - 84
1 Mar 2008
Vendittoli P Duval N Lavoie P
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One hundred and forty eight hybrid total hip arthroplasties in patients less than seventy years old were randomised to metal on polyethylene or alumina on alumina bearing surfaces. At two to seven years of follow-up, no significant difference was found on hip scores or survivorship of the implants. No specific complication associated to alumina components like fracture or malpositionning of the acetabular insert were observed. Alumina on alumina bearing surfaces give early clinical and radiological results similar to metal on polyethylene, suggesting that they have a potential to become good bearing surfaces in hip arthroplasty for young patients. The excellent results obtained with metal-polyethylene (M-P) bearing surfaces in total hip arthroplasty (THA) are still limited by the production of polyethylene wear debris, osteolysis and aseptic loosening. Because of it superior tribologic properties and bioinert composition, alumina-alumina (AL-AL) bearing surfaces are proposed to improve survival of THA but previously reported early complications prevented widespread use of alumina ceramic. This study compares early results and complication with Ceraver M-P and AL-AL THA. One hundred forty-eight Ceraver hybrid THA in patients less than seventy years old were randomised to M-P or AL-AL bearing surfaces. We present the clinical and radiological results for patients two to seven years after their surgery. No significant difference was found on W.O.M.A.C. and Merle D’Aubigné Postel scores. No specific complication associated with alumina components like fracture or malpositionning of the acetabular insert were observed in this study. Documented complications were: infection 4 AL-AL/2 M-P; dislocation 1 AL-AL/4 M-P; and heterotopic ossification 47% AL-AL/24% M-P. No aseptic loosening was observed. Ceraver AL-AL bearing surfaces give early clinical and radiological results similar to M-P. Our results are in accordance with studies suggesting that AL-AL have a potential to become good bearing surfaces in THA in the young patients. Funding: funding was obtained from Ceraver, Paris to perform this study


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_IV | Pages 528 - 528
1 Oct 2010
Pospischill M Knahr K Pokorny A
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Aims: The aim of this study is to present long-term results of the cementless Alloclassic total hip arthroplasty system of up to 21 years. Matarial and Methods: 152 consecutive primary hip arthroplasties using a threaded conical titanium cup (Alloclassic CSF) and a rectangular titanium press-fit stem (Alloclassic SL) were implanted between September 1987 and December 1988. In all cases a 32 mm alumina ceramic head and a UHMW polyethylene inlay were used. Clinical and radiological results were available for 55 patients (36,2%) with a minimum of 15 years (15.0 to 20.9 years). Clinical results were evaluated according to the Harris Hip Score, the SF-36 and WOMAC score. Radiographic results were analysed on anteroposterior x-rays according to the method of DeLee and Charnley for the cup and of Gruen for the stem. Results: The average Harris Hip Score at the last follow-up was 87.3. The mean pain score was 41.5, the mean functional score 47.3. Radiographic results showed osteolytic lesions around the cup in one case. Radiolucent lines around the stem were observed only in the proximal zones in 2/3 of the cases, cortical hyperthrophy occurred in the distal zones in ¾ of the evaluated hips. 23 hips (15.1%) needed revision surgery. The majority (17 hips – 73.9% of all reoperations) were revised due to progressive Polyethylene wear, all after a minimum of ten years. Exchange of the polyethylene inlay and the ceramic head was performed in 14 hips. In two cases the acetabular component and in one case the femoral component were found to be loose intraoperatively because of the wear debris and had to be exchanged. 4 hips had to be revised due to aseptic cup loosening without signs of increased polyethylene wear. There was one revision due to a late deep infection and one because of a periprothetic femoral fracture. Conclusion: Our data suggest that excellent long-term results can be achieved with the cementless Alloclassic system. The main limiting factor for implant survival was found in increased polyethylene wear. We therefore recommend early exchange of the inlay to avoid loosening and the use of modern wear couples such as ceramic-on-ceramic, metal-on-metal or crosslinked polyethylene


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 104 - 104
1 Mar 2010
Walter WL Gillies M Donohoo S Sexton SA Hozack WJ Ranawat AS
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Squeaking in ceramic on ceramic bearing total hip arthroplasty is well documented but its aetiology is poorly understood. In this study we have undertaken an acoustic analysis of the squeaking sound recorded from 31 ceramic on ceramic bearing hips. The frequencies of these sounds were compared with in vitro acoustic analysis of the component parts of the total hip implant. Analysis of the sounds produced by squeaking hip replacements and comparison of the frequencies of these sounds with the natural frequency of the component parts of the hip replacements indicates that the squeaking sound is due to a friction driven forced vibration resulting in resonance of one or both of the metal components of the implant. Finite element analysis of edge loading of the prostheses shows that there is a stiffness incompatibility between the acetabular shell and the liner. The shell tends to deform, uncoupling the shell-liner taper system. As a result the liner tends to tilt out of the acetabular shell and slide against the acetabular shell adjacent to the applied load. The amount of sliding varied from 4–40μm. In vitro acoustic and finite element analysis of the component parts of a total hip replacement compared with in vivo acoustic analysis of squeaking hips indicate that either the acetabular shell or the femoral stem can act as an “oscillator’ in a forced vibration system and thus emit a squeak. Introduction: Squeaking has long been recognized as a complication in hip arthroplasty. It was first reported in the Judet acrylic hemiarthroplasty. 1. It was the squeak of a Judet prosthesis that led John Charnley to investigate friction and lubrication of normal and artificial joints which ultimately led to the concept of low friction arthroplasty. Ceramic on ceramic bearings were pioneered by Boutin in France during the 1970’s, but experienced unacceptably high fracture rates. Charnley demonstrated in vitro squeaking when he tested one of Boutin’s ceramic-on-ceramic bearings in his pendulum friction comparator. 2. Squeaking has also been reported in other hard on hard bearings, and can also occur after polyethylene bearing surface failure resulting in articulation between metal on metal or ceramic on metal surfaces. 3–6. Recently, squeaking has been increasingly reported in modern ceramic-on-ceramic bearings in hip arthroplasty. However, although well-documented, the aetiology of squeaking in ceramic on ceramic bearings is still poorly understood. The incidence ranges from under 1% to 10%. 7–10. It has been reported in mismatched ceramic couples,11and after ceramic liner fracture. 12,13. An increased risk of squeaking has been demonstrated with acetabular component malposition, as well as in younger, heavier and taller patients. 9. However, it may also occur in properly matched ceramic bearings with ideal acetabular component position and in the absence of neck to rim impingement. 7–9. In rare cases, the squeak is not tolerated by the patient and has prompted a revision. Under ideal conditions hard-on-hard bearings are assumed to be operating under conditions of fluid film lubrication with very low friction. 14,15. However, if fluid film lubrication breaks down leading to dry sliding contact there will be a dramatic increase in friction. If this increased friction provides more energy to the system than it can dissipate, instabilities may develop in the form of friction induced vibrations and sound radiation. 16. Friction induced vibrations are a special case of forced vibration, where the frequency of the resulting vibration is determined by the natural frequency of the component parts. Running a moistened finger around the rim of a wine glass is an example of this. [Appendix]. The hypothesis of this study is that the squeaking sound that occurs in ceramic on ceramic hip replacement is the result of a forced vibration. This forced vibration can be broken down into a driving force and a resultant dynamic response. 17. The driving force is a frictional driving force and occurs when there is a loss of fluid film lubrication resulting in a high friction force. 14,15,18. The dynamic response is a vibration of a part of the device (the oscillator) at a frequency that is influenced by the natural frequency of the part. 16. By analyzing the frequencies of the sound produced by squeaking hip replacements and comparing them to the natural frequency of the component parts of a hip replacement this study aims to determine which part produces the sound. Materials and methods: In vitro determination of the natural frequencies of implant components Modal analysis has suggested that resonance of the ceramic components would occur only at frequencies above the human audible range and that resonance of the metal parts would occur at frequencies within the human audible range. Furthermore, that resonance of the combined ceramic insert and titanium shell would not be within the human audible range. To test this hypothesis we performed a simple acoustic analysis. The natural frequency of hip replacement components was determined experimentally using an impulse-excitation method (Grindo-sonic). Components were placed on a soft foam mat in a quiet environment and struck with a wooden mallet. The sound emitted from the component was recorded on a personal computer with an external microphone with a frequency response which ranges from 50Hz to 18,000Hz (Beyerdynamic MCE87, Heilbronn, Ger-many). The computer has an integrated sound card with a frequency response from 20Hz to 24kHz (SoundMAX integrated digital audio chip, Analogue Devices Inc, Norwood, M.A.) and we used a codec with a frequency response from 20Hz to 20kHz (Audio Codec ’97, Intel, Santa Clara, CA). Sound files were captured as 16 bit mono files at a sample rate of 48000Hz using acoustic analysis software (Adobe Audition 1.5, Adobe Systems Incorporated, San Jose, California, USA). We performed fast Fourier transform (FFT) of the sound using FFT size 1024 with a Blackmann-Harris window to detect the frequency components of the emitted sound. (Fast Fourier transform is an accepted and efficient algorithm which enables construction of a frequency spectrum of digitized sound). We tested the following components: modular ceramic/titanium acetabular components, which included testing the titanium shell and the respective ceramic inserts both assembled according to the manufacturer’s instructions and unassembled; titanium femoral stems and ceramic femoral heads both assembled and unassembled. A range of sizes of each component was tested according to availability from our retrieval collection. In vivo acoustic analysis: Sound recordings were collected from 31 patients. Nineteen recordings were made at our institution: 16 of these were video and audio recordings and 3 were audio only recordings. Video recording was with a digital video camera recorder (Sony DCR-DVD101E Sony Electronics, San Diego, CA, USA) with the same external microphone used in the in vitro analysis. For 3 patients who could not reproduce the sound in the office we lent them a digital sound recorder for them to take home and record the sound when it occurred (Sony ICD-MX20, Sony Electronics, San Diego, CA, USA). This device has a In vivo acoustic frequency range from 60Hz to 13,500Hz. The remainder of the recordings were video and audio recordings made by surgeons at three other institutions on digital video camera recorders. Sound files were captured and analyzed by the same method used in the in vitro analysis. Each recording was previewed in the spectral view mode which allows easy visual identification of the squeak in the sound recording. In addition all sound recordings were played, listening for the squeak. Once a squeak was identified a fast Fourier transform (FFT) was performed. We used FFT size 1024 with a Blackmann-Harris window which allowed us to easily pick out the major frequency components. All prominent frequency components were recorded at the beginning of the squeak and at several time points during the squeak if there was any change. A range was recorded for the fundamental frequency component. We were able to determine the frequency range of the recording device used by observing the frequency range of the background noise on the recording. We found that if a squeak was audible on the recording we had no difficulty determining its frequency regardless of the quality of the device used to make the recording or the amount of background noise. The mean age of the patients was 54 years (23 to 79 years), mean height was 171cm (152 to 186cm) and mean weight was 79kg (52 to 111kg). There were 17 female and 14 male patients. There were nineteen ABGII stem and ABGII cup combinations, 10 accolade stem and trident cup, 1 Exeter stem and trident cup and 1 Osteonics Securfit stem with an Osteonics cup. Ethics committee approval was obtained for this project from our institution and from the referring institutions and informed consent was gained from the patients. Finite element analysis of edge loading: Edge-loading wear which may provide a mechanism for failure of fluid film lubrication and may therefore play a role in squeaking. To evaluate edge loading further we conducted finite-element analysis (FEA). 9. Computed tomography (CT) scans of an intact pelvis were obtained from visual human data set (VHD, NLM, Bethesda, Maryland). Slices were taken at 1mm thick with no inter-slice distance through the entire pelvis. The CT files were then read into a contour extraction program and saved into an IGES file format which was imported into PATRAN (MSC Software, Los Angeles, CA) to develop the pelvic geometry. The pelvis was meshed with 10 noded modified tetrahedral elements. The model was reconstructed with a 54mm titanium alloy generic acetabular shell and a 28mm alumina ceramic liner. The acetabular shell and ceramic liner were meshed using 8 noded hexahedral elements. The shell-liner modular taper junction incorporated an 18° angle. The implant contact conditions (Lagrangian multiplier) allowed the liner and shell to slide with a friction coefficient of 0.9. Tied contact conditions were applied between the generic acetabular shell and the bone representing bone ongrowth. Bone material properties were extracted from the CT files by taking the Hounsfield value and the coordinates and mapping to the element in the model allowing us to calculate the Young’s modulus for each element . 19. Material properties for the shell and liner were based on published values. 20. for titanium alloy and alumina ceramic


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 50 - 51
1 Mar 2009
Pospischill M Knahr K
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Aims: The aim of this study is to present clinical and radiographic long-term results including a survival analysis of the cementless Alloclassic total hip arthroplasty system. Matarial and Methods: 103 consecutive primary hip arthroplasties using a threaded conical titanium cup (Alloclassic CSF) and a rectangular titanium pressfit stem (Alloclassic SL) were evaluated clinically and radiographically with an average follow-up period of 14.4 years (range 10.2 to 17.1 years). In all cases a 32 mm alumina ceramic head and a UHMW polyethylene inlay were used. Clinical results were evaluated according to the Harris Hip Score, the SF-36 and WOMAC score. Radiographic results were analysed on antero-posterior x-rays. A statistical survivorship analysis was calculated using Kaplan-Meier curves. Results: The average Harris Hip Score at the last follow-up was 89.2. The mean pain score was 41.6, the mean functional score 47.6. Radiographic results showed a continuous radiolucency around the cup in three cases. Radiolucent lines around the stem were observed only in the proximal zone 1 in 52 and in zone 7 in 26 cases. Cortical hyperthrophy occurred in the distal zone 3 in 33 cases and in zone 5 in 72 cases. Fifteen hips were revised, eleven of them because of increased polyethylene wear after a minimum follow-up of 10 years. One patient needed revision due to a late deep infection after 7.4 years. There were three cases of aseptic loosening without signs of progressive polyethylene wear that led to a cup exchange. The cumulative survivorship with revision due to aseptic component loosening as endpoint was 95.6 % for the cup and 100 % for the stem after 15 years. Conclusion: Our data suggest that excellent long-term results can be achieved with the cementless Alloclassic system. The main limiting factor for implant survival was found in increased polyethylene wear. We therefore recommend early exchange of the inlay to avoid component loosening and the use of modern wear couples such as ceramic-on-ceramic, metal-on-metal or crosslinked polyethylene


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 229 - 229
1 Sep 2012
Masson B Pandorf T
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Introduction. In total hip arthroplasty ceramic on ceramic bearing couples are used more and more frequently and on a wordwide basis. The main reason of this choice is reduction of wear debris and osteolysis. The tribological properties and the mechanical behaviour of the implanted ceramic must remain the same throughout the patient's life. The aim of this study was to evaluate the resistance of Alumina Matrix Composite to environmental degradation. Material and method. The alumina matrix composite or BIOLOX ® delta is manufactured in Germany by CeramTec. It is made up of 80 vol.% Al2O3, 17 vol.% Yttria Stabilized ZrO2 and 3vol.% strontium aluminate platelets. The zirconia grains account for 1.3 mol.% of the Yttria content. Accelerated aging tests in water steam at 142°C, 134°C, 121°C, and 105°C were performed to evaluate the aging kinetics of the composite. X-ray diffraction was used to determine the monoclinic phase content on the material surface. Phase transformation is associated with weakness and increase in roughness of zirconia ceramic implants. Results. The data below shows average monoclinic contents before and after aging in water vapour according to the ISO standard test (134°C, 2 bars water steam, 10 h) on the surface and inside the 28 mm taper(12/14 taper) femoral ball heads manufactured in alumina ceramic composite. There are precisions concerning the roughness and the load to failure before and after aging concerning 28mm diameter heads. Before Aging 13%+/-3% of Monoclinic content. After 10 H at 134°C23%+/-3% of Monoclinic content the roughness of the polished surface remain the same (5nm+/− 2). The load to failure of 28 mm heads before aging is 76 kN +/− 5kN, and 72 kN +/− 5kN after aging. The results show that although a rise in monoclinic content is predictable after long aging duration in vivo, the impact of the transformation is quite different to monolithic zirconia. A zirconia femoral head exhibits an important increase of roughness from 2 nm to more than 50 nm when submitted to the same duration of ageing. Other tests with hip simulators under severe micro separation have been done to analyse the impact of aging on wear performance. The main wear zone on femoral heads underwent a phase transformation from tetragonal to monoclinic (23% monoclinic) at 5 milion cycles duration without any change in roughness after 5Mc duration. Conclusion. This experimental testing program has enabled a prediction for the long-term in vivo environmental resistance of prostheses made out of Alumina Matrix Composite. The substantial improvement in mechanical properties and the excellent wear behaviour, even under severe microseparation conditions has been clinically confirmed. Today more than 960,000 ceramic ball heads and more than 450 000 ceramic inserts made of the alumina matrix composite have been implanted. Additionally, due to enhanced mechanical behaviour, new applications in orthopaedics are possible


Bone & Joint Open
Vol. 5, Issue 4 | Pages 286 - 293
9 Apr 2024
Upadhyay PK Kumar V Mirza SB Shah N

Aims

This study reports the results of 38 total hip arthroplasties (THAs) in 33 patients aged less than 50 years, using the JRI Furlong hydroxyapatite ceramic (HAC)-coated femoral component.

Methods

We describe the survival, radiological, and functional outcomes of 33 patients (38 THAs) at a mean follow-up of 27 years (25 to 32) between 1988 and 2018.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_I | Pages 7 - 7
1 Mar 2006
Fisher J
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Wear and wear debris induced osteolysis is recognised as a major cause of long term failure in hip prostheses. Historically ultra high molecular weight polyethylene acetabular cups produced micron and submicron wear particles which accumulated in peri prosthetic tissues, and stimulated macrophages to generate wear debris induced osteolysis. Acceleration of wear and osteolysis was caused in historical materials by oxidative degradation of the polyethylene following gamma irradiation in air, and by third body damage and scratching of metallic femoral heads. Current conventional ultra high molecular weight polyethylene cups are irradiated in an inert atmosphere to reduce oxidative degradation and are articulated against ceramic femoral heads to reduce third body wear. More recently modified highly cross linked polyethylene has been developed, and while these materials produce a four to five fold reduction in wear volume the wear particles have been found to be more reactive, resulting in only a two fold reduction in functional osteolytic potential. The question remains as to whether this performance is adequate for high demand patients, particularly if larger diameter femoral heads are to be used. Recent interest in improved function, stability and reducing dislocations has generated interest in using larger diameter heads and hard on hard bearings. Alumina ceramic on ceramic bearings have shown a one hundred fold decrease in wear compared to highly cross linked polyethylene materials, and cell culture studies have shown the wear particles to be more bio-compatible and less osteolytic potential. Metal on metal bearings also produced very low wear rates compared to polyethylene. The wear particles are very small, 10 to 50 nanometers in size, some concern remains about the systematic release of metallic ions. These are lubrication sensitive bearings, and they unlike polyethylene wear decreases as the head size increases due to improved lubrication. Size 36 mm metal bearings are now commonplace for total joint replacements with even larger head sizes being used for surface replacement solutions. The demand for increased function and improved stability is leading to increased use of hard on hard bearings with larger diameter heads


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_II | Pages 313 - 313
1 May 2010
Williams S Brockett C Hardaker C Isaac G Fisher J
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Ceramic-on-metal (ceramic head and metal liner, COM) hip replacements have shown reduced wear in comparison to metal-on-metal (MOM) bearings (Firkins et al., 1999). This has been attributed to a reduction in corrosive wear, differential hardness and a reduction in adhesive wear. In a clinical report on the use of a metal-on-ceramic hip replacement (Valenti et al., 2007) which consisted of a stainless steel head and alumina ceramic insert at revision 6-months post-op massive metallosis and macroscopic wear was observed. The aim of this study was to assess the performance of ceramic and metal bearings in different configurations under adverse conditions, ceramic heads on metal liners (COM) were compared to metal heads on ceramic inserts (MOC), with head on cup rim loading under micro-separation hip joint simulation. Components used were made of zirconia-platelet toughened alumina (Biolox Delta) and high carbon (0.2wt%) CoCrMo alloy (DePuy International Ltd, UK). Hip simulator testing applied a twin-peak loading cycle and walking motions with the prosthesis in the anatomical position. The lubricant (25% calf-serum) was changed every 0.33Mc, wear was measured gravimetrically. Testing was conducted for 2-million cycles, a standard simulator cycle was adapted so the head subluxed in the swing phase forcing the head onto the cup rim at heel strike (Williams et al., 2006). The total overall mean wear rate for the MOC bearings (0.71±0.30mm3/Mc) was significantly higher than the wear rate for the COM bearings (0.09±0.025mm3/Mc). The contact of the head against the rim of the cup at heel strike caused deep stripe wear on the metallic heads of the MOC bearings. This region on the head is exposed to high stress conditions and susceptible to damage in edge contact, the effect of this is increased when the cup is a harder material than the head. The wear of a metal-on-metal (MOM) couple under similar conditions was almost two-fold greater than the MOC couple (1.58mm3/Mc, Williams et al., 2006) providing further evidence of the reduced wear with COM in comparison to MOM. The explant described Valenti et al. included a stainless steel head, this is a softer material compared to CoCr, and wears at a higher level. It can be postulated that the wear under adverse conditions would be further increased. The COM concept can provide increased design flexibility; thin metal shells can be used with larger ceramic heads. Additionally the design protects against ceramic liner chipping. COM bearings are currently undergoing clinical trials, early data suggests reduced metal ion release in patients with COM bearings compared to metal-on-metal (Williams et al., 2007)