Introduction. Highly cross-linked polyethylene has been introduced to decrease osteolysis secondary to polyethylene wear debris generation, but there are few long-term data on revision total hip arthroplasty using highly cross-linked polyethylene liners. The purpose of this study was to report the long-term radiographic and clinical outcomes of a highly cross-linked polyethylene liner in revision total hip arthroplasty. Materials & Methods. We analyzed 63 revision total hip arthoplasties that were performed in 63 patients using a highly cross-linked polyethylene liner between April 2000 and February 2005. Of these, nine died and four were lost to follow-up before the end of the 10-year evaluation. Thus, the final study cohort consisted of 50 patients (50 hips). There were 26 males and 24 females with a mean age at time of revision total hip arthoplasty of 53 years (range, 27–75 years). Mean duration of follow-up was 11 years (range, 10–14 years). Results. Mean Harris hip score improved from 44 points preoperatively to 85 points at final follow-up. No radiographic evidence of osteolysis was found in any hip. One hip required re-revision surgery for acetabular cup loosening at 6.5 years postoperatively. One required re-revision with a constrained liner because of recurrent dislocation. Three sustained deep infections requiring additional surgical procedures. Kaplan-Meier survivorship with an end point of re-revision for any reason was 91.0% and for aseptic cup loosening was 97.9% at 11 years (Figs. 1 and 2). Conclusions. At a minimum of 10 years, the highly cross-linked polyethylene liners showed excellent clinical performance and implant survivorship, and were not associated with osteolysis in our group of patients with revision total hip arthoplasties

Introduction. Technological advances in the processing of polyethylene have led to improved survivorship of total hip arthroplasty. The purpose of this study was to determine if a second generation highly cross-linked polyethylene could improve upon wear rates compared to conventional and first generation cross-linked polyethylene in patients undergoing primary total hip arthroplasty. Methods. Linear and volumetric wear rates of a second generation highly cross-linked polyethylene were evaluated following primary total hip arthroplasty. There were 44 patients with an average age of 68.6 years and mean follow-up of 5.3 years. Patients were evaluated at six weeks, one, two and five years. Wear rates were determined from digitized AP Pelvis radiograph by an independent observer using Martell's software. Acetabular inclination and femoral head size were also evaluated to determine variability in wear rates. Results. The mean linear wear rate for the entire group was 0.015mm/year (±0.055). There was a 64% decrease in linear wear rate when compared to a first generation highly cross-linked polyethylene from the same institution. There was a 90% decrease in wear rate compared to conventional polyethylene. There were no differences in the linear wear rate between the 32mm vs. larger head sizes (36mm and 40mm). However, there was a 30% increase in volumetric wear rate with larger head sizes. The mean wear rate in patients with cup inclination less than 45 degrees was 0.006mm/year compared with 0.024mm/year for those with an inclination greater than 45 degrees. The amount of linear wear was increased by 4 times in patients with a cup inclination of greater than 45 degrees. There was no evidence of any osteolysis in this group of patients. Conclusion. Our data with a mean follow-up of 5.3 years, using a second generation highly cross-linked polyethylene, demonstrates a dramatic decrease in incidents of linear wear compared to conventional polyethylene and first generation highly cross-linked polyethylene (Figure 1). Of concern is the higher volumetric wear rate noted with larger head sizes and increased linear wear rates with cup inclination angles of greater than 45 degrees. Despite improvements in wear rates using a second generation highly cross-linked polyethylene, cup orientation and choice of head size play significant roles in implant survivorship

Background. Cross-linked polyethylene has much less wear than conventional polyethylene and can used in a more bone conserving thickness of 4 mm. We have used it for hip resurfacing since 2001. Questions/Purposes. This study evaluated the effectiveness of a highly cross-linked polyethylene acetabular component for hip resurfacing in patients under age 50. I posed 5 questions: (1) What are the functional results, (2) What are the complications, (3) What is the 10-year implant survivorship, (4) What is the femoral head penetration into the polyethylene, and (5) What is the bone conservation?. Participants and Methods. There were 160 resurfacing procedures (144 participants) using a 2 piece acetabular shell and a cobalt chromium femoral component (fig. 1). Participants averaged 43 years of age at the time of surgery (range, 23 – 49.5 years) and 70% were women. Inclusion criteria were patients with adequate acetabular bone and a high enough head-neck ratio so that the reconstruction would not violate the femoral neck cortices or medial acetabular wall. The largest cross-linked polyethylene available was 49 mm so only patients with smaller femoral geometries were included. The Harris, WOMAC, and UCLA hip scores were used to assess pain, activity, and function and participants were asked about their satisfaction with the procedure. Digital radiography and computed tomographic scans were used to evaluate femoral head penetration and osteolysis. Removed polyethylene liners were analyzed. Results. The median follow-up was 11.5 years (range, 10 – 14 years). One participant was lost to follow-up and 1 died. The mean Harris Hip Score was 95 and 95% of the participants rated the results of their procedure as excellent. The average UCLA activity score was 8. One patient underwent successful revision surgery for acetabular loosening. Four participants underwent successful revision to a total hip replacement because of femoral neck fracture (2), femoral loosening, or infection. The Kaplan-Meier survivorship was 96%. There were no revisions for polyethylene wear and there were no instances of osteolysis. The medial acetabular wall thickness averaged 7.3 mm (range, 1.5 mm – 14.9 mm). The mean inclination angle was 39°. The mean femoral head penetration was 0.05 mm/year (range, .028 – .09 mm/year). Conclusions. Hip resurfacing with a highly cross-linked polyethylene acetabular component is a reliable procedure at mid-term follow-up. The rate of polyethylene wear is below the osteolytic threshold of .1 mm/yr. The preservation of both acetabular and femoral bone is reasonable even in comparison to thin metal shells available for metal-on-metal resurfacing and total hip replacement. The functional results are comparable to those of metal-on-metal resurfacing without the concerns of a metal bearing couple. The procedures are demanding and patient selection is critical to the success of the procedure. Although long-term follow-up is needed to determine if implant survivorship with highly cross-linked polyethylene acetabular components will equal that of metal-on-metal prostheses, the low rate of femoral head penetration suggests that many years of use in young highly active participants are possible

Background. The advent of highly cross-linked polyethylene has resulted in improved wear rates and reduced osteolysis with at least intermediate follow-up when compared to conventional polyethylene. However, the role of alternative femoral head bearing materials in decreasing wear is less clear. The purpose of this study was to determine in-vivo polyethylene wear rates across ceramic, Oxinium, and cobalt chrome femoral head articulations. Methods. A review of our institutional database was performed to identify patients who underwent a total hip arthroplasty using either ceramic or oxidized zirconium (Oxinium) femoral head components on highly cross-linked polyethylene between 2008 and 2011. These patients were then matched on implant type, age, sex and BMI with patients who had a cobalt chrome bearing implant during the same time period. RSA analysis was performed using the center index method to measure femoral head penetration (polyethylene wear). Secondary quality of life outcomes were collected using WOMAC and HHS Scores. Paired analyses were performed to detect differences in wear rate (mm/year) between the cobalt chrome cohorts and their matched ceramic and Oxinium cohorts. Additional independent group comparisons were performed by analysis of variance with the control groups collapsed to determine wear rate differences between all three cohorts. Results. A total of 75 patients underwent RSA analysis. 20 patients with a ceramic femoral head component and 16 patients with an Oxinium femoral head component along with the same number of matched patients with cobalt chrome femoral head component were included in the analysis. The time in vivo for the Oxinium (5.17 +/− 0.96 years), Oxinium matched cohort (5.13 +/− 0.72 years), ceramic (5.15 +/− 0.76 years) and ceramic matched cohort (5.36 +/− 0.63 years) were comparable. The demographics of all bearing surface cohorts were similar. The paired comparison between the Oxinium and cobalt chrome cohorts (0.32 vs. 0.28 mm/year, p=0.427) and ceramic vs cobalt chrome cohorts (0.28 vs. 0.22 mm/year, p=0.202) did not demonstrate a significant difference in wear rate. The independent groups analysis revealed a significantly higher wear rate of Oxinium (0.33 mm/year) compared to cobalt chrome (0.24 mm/year) (p = 0. 038). There were no differences in HHS and WOMAC scores between the Oxinium and cobalt chrome cohorts (HHS: p = 0.71, WOMAC: p=0.08) or the ceramic and cobalt chrome cohorts (HHS: p=0.15, WOMAC: p =023). Conclusion. This study presents evidence of a greater wear rate (mm/year) of the Oxinium femoral head component compared to a cobalt chrome femoral head component. This difference was not demonstrated in the ceramic femoral head component. Despite this difference, there were no clinical differences as measured by the HHS and WOMAC. Future research should focus on factors that may contribute to the higher wear rate seen in the Oxinium cohort. Level of Evidence – Level II. Disclosures - Institutional support provided by Depuy, Stryker, and Smith and Nephew

The advent of highly cross-linked polyethylene has resulted in improved wear rates and reduced osteolysis with at least intermediate follow-up when compared to conventional polyethylene. However, the role of alternative femoral head bearing materials in decreasing wear is less clear. The purpose of this study was to determine in-vivo polyethylene wear rates across ceramic, Oxinium, and cobalt chrome femoral head articulations. A review of our institutional database was performed to identify patients who underwent a total hip arthroplasty using either ceramic or oxidised zirconium (Oxinium) femoral head components on highly cross-linked polyethylene between 2008 and 2011. These patients were then matched on implant type, age, sex and BMI with patients who had a cobalt chrome bearing implant during the same time period. RSA analysis was performed using the centre index method to measure femoral head penetration (polyethylene wear). Secondary quality of life outcomes were collected using WOMAC and HHS Scores. Paired analyses were performed to detect differences in wear rate (mm/year) between the cobalt chrome cohorts and their matched ceramic and Oxinium cohorts. Additional independent group comparisons were performed by analysis of variance with the control groups collapsed to determine wear rate differences between all three cohorts. A total of 68 patients underwent RSA analysis. Fifteen patients with a ceramic femoral head component and 14 patients with an Oxinium femoral head component along with the same number of matched patients with cobalt chrome femoral head component were included in the analysis. The time in vivo for the Oxinium (5.17 +/− 0.96 years), Oxinium matched cohort (5.13 +/− 0.72 years), ceramic (5.15 +/− 0.76 years) and ceramic matched cohort (5.36 +/− 0.63 years) were comparable. The demographics of all bearing surface cohorts were similar. The paired comparison between the Oxinium and cobalt chrome cohorts (0.33 vs. 0.29 mm/year, p=0.284) and ceramic vs cobalt chrome cohorts (0.26 vs. 0.20 mm/year, p=0.137) did not demonstrate a significant difference in wear rate. The independent groups analysis revealed a significantly higher wear rate of Oxinium (0.33 mm/year) compared to cobalt chrome (0.24 mm/year) (p = 0. 038). There were no differences in HHS and WOMAC scores between the Oxinium and cobalt chrome cohorts (HHS: p = 0.71, WOMAC: p=0.08) or the ceramic and cobalt chrome cohorts (HHS: p=0.15, WOMAC: p=023). This study presents evidence of a greater wear rate (mm/year) of the Oxinium femoral head component compared to a cobalt chrome femoral head component. This difference was not demonstrated in the ceramic femoral head component. Despite this difference, there were no clinical differences as measured by the HHS and WOMAC. Future research should focus on factors that may contribute to the higher wear rate seen in the Oxinium cohort

Introduction. Vitamin-E (VE, dl-α-tocopherol) is a powerful antioxidant for highly cross-linked polyethylene (XLPE). It was previously reported that VE-stabilized XLPE succeeded in retaining no measurable oxidation even after accelerated aging tests combined with cyclic loading or lipid absorption. Thus, VE-stabilized XLPE is nowadays recognized worldwide as one of the new standard materials in total hip arthroplasty (THA). However, the effects of such VE addition on physical behavior of polyethylene remain to be fully elucidated by contrast to the clear statement of its chemical role (i.e., the enhanced oxidation resistance) in the published literature. In this presentation, we shall attempt to provide those missing notations and to explore the microstructural and biomechanical role of VE in XLPE acetabular liner on the molecular scale. Methods. The two different types of XLPE acetabular liners, VE-blended and VE-free (no VE-blended) component (n=3 for each sample), were investigated by means of laser-scanning confocal polarized micro-Raman spectroscopy. In both components, the cross-linking was achieved by electron-beam irradiation with a total dose of 300kGy in vacuum. Raman spectroscopy offers non-destructive, contactless, and high-resolution analyses of polymer morphologies. In this study, we performed an in-depth profiling of crystalline and non-crystalline phase (i.e., amorphous and intermediate phase between crystalline and amorphous regions) percentages and degree of molecular orientation in the above two liners before and after introducing the 10% plastic deformation via uniaxial compression loading at room temperature. These results were also compared to the morphological analyses under the same compression conditions performed on the virgin conventional polyethylene (Virgin liner) without radiation crosslinking as well as VE blending. Results. In the deformed state, Virgin and VE-blended liner showed a pronounced development of the surface crystalline texture. On the other hand, deformation-induced texturing occurred at much less extent in VE-free liner. According to the results of phase percentages, there was no crystallinity change in VE-blended liner by contrast to the marked increase of crystallinity in Virgin and VE-free liner after compression deformation. Alternatively, amorphous-to-intermediate phase transition was confirmed in VE-blended liner. Discussion/Conclusion. We found molecular rearrangement and phase transitions in crystalline and non-crystalline phase as a reconstruction process after plastic deformation in the investigated samples, which can be deeply related to their wear and mechanical properties. The morphological comparisons between Virgin and VE-free liner suggested that the intermolecular cross-linked networks in polyethylene highly restricted the molecular chain mobility as evidenced by few texture evolutions in VE-free liner. On the other hand, the comparisons between VE-free/-blended liner indicated that the presence of VE might promote molecular chain mobility even in the cross-linked structure, resulting in the significant surface texturing. These physical and structural aspects of VE blending would imply the possibility of the increased micromechanical wear through the strain-softening and weakening phenomena due to the molecular reorientation during in-vivo service. However, in other words, wear resistance of VE-blended liner might be further maximized by the more rigid control of molecular movements

Current implant designs and materials provide a high grade of quality and safety, but aseptic implant loosening is still the main reason for total hip revision. Highly cross-linked polyethylene (HX-PE) is used successfully in total hip replacements (THR) since several years. The good wear properties lead to a reduction of wear debris and may contribute to a longer survival time of the THRs. Furthermore, thin HX-PE liner allows the use of larger femoral heads associated with a decreased risk of dislocation and an improved range of motion. However, the cross-linking process is associated with a loss of mechanical properties of the polyethylene material which compromise the use of thin HX-PE liner in terms of high stress situations. The aim of the present study was the experimental wear analysis of HX-PE liner under steep acetabular cup position. Furthermore, a finite element analysis (FEA) was performed in order to calculate the stress within the HX-PE material in case of steep cup position under physiological loading. Experimental wear testing was performed for 5 Mio load cycles, using highly cross-linked polyethylene (HX-PE) acetabular liner combined with 44 mm ceramic femoral heads at a standard position of the acetabular cup (30° inclination) according to ISO 14242 as well as at 60° cup inclination. The wall thickness of the HX-PE liner was 3.8 mm. A hip wear simulator, according to ISO 14242 (EndoLab GmbH, Rosenheim, Germany), was used and wear was determined gravimetrically. Moreover, finite element models of the THR system at standard and steep cup position was created by Abaqus/CAE (Dessault Systemes Providence, USA). Using the finite element software Abaqus (Dessault Systemes Providence, USA) the total hip implants were physiologically loaded with maximum force of the gait cycle (3.0 kN). Thereby, the stresses within the HX-PE material were analysed. The average gravimetrical wear rates of the HX-PE liners at standard implant position (30°) and 60° cup inclination showed small wear amounts of 3.15 ± 0.32 mg and 1.92 ± 1.00 mg per million cycles, respectively. The FEA revealed a clear increase of stresses at the HX-PE liner with respect to steep cup position (von Mises stress of 8.78 MPa) compared to ISO standard implant position (von Mises stress of 5.70 MPa). The wear simulator tests could not demonstrate significant differences of gravimetrical wear amount of HX-PE liners under steep hip cup position compared to standard implant position. The small contact surface between the femoral head and the SX-PE liner during the wear testing may lead to the low wear rate of the misaligned acetabluar cup. Moreover, the FEA showed that the effect of a misaligned acetabular cup on the stresses within the polyethylene liner can be critical. Although an increase of wear could not be detected a steeper acetabular cup position using thin HX-PE liners should be avoided due to higher stresses preventing implant failure in clinical application

Background. Wear and osteolysis are major contributors, which limit the durability of total hip Arthroplasty (THA) and ultimately cause it to fail. Efforts were made to decrease wear by highly cross-linked polyethylene (HXLPE) and using ceramic bearings. Questions/Purposes. The purpose of this study is to analyze and compare the five year performance of large sized (32mm and 36mm) ceramic and metal heads on X3 HXLPE (Stryker, Mahwah, NJ, USA). Materials and Methods. One hundred and twenty near-consecutive patients that underwent primary THA between January 2006 and December 2009 for osteoarthritis with five-year radiographic and clinical follow-up were identified from our institutional review board-approved prospective database. All patients received a non-cemented THA with larger femoral head (32 or larger) on X3 HXLPE, either a ceramic (n=60) or metal (n=60). Linear and volumetric wear was measured using the computer-assisted Roman software. Results. At final follow up, the mean wear rates were not significantly different (p=0.63): 0.018 ± 0.06 mm/yr and 0.021 ± 0.06 mm/yr for ceramic-on-X3 and metal-on-X3, respectively. When negative values were considered zero as worst-case scenario, wear rates for ceramic-on-X3 and metal-on-X3 HXLPE groups were 0.032 ± 0.04 mm/yr and 0.041 ± 0.05 mm/yr, respectively (P=0.55). Mean volumetric wear rates were also statistically similar: 68.56 mm3/y and 79.96 mm3/y for the ceramic-on-X3 and metal-on-X3 HXLPE groups respectively (p=0.78); when negatives were considered zeroes, they were 121.42 mm3/y and 164.63 mm3/y, respectively (p=0.20). Patients with ceramic heads were significantly younger (p <0.01), more active (p<0.01) and had better clinical scores than those with metal heads. Conclusions. Large ceramic and metal heads on HXLPE have excellent durability at minimum 5 years followup without any statistical significant difference in linear or volumetric wear rates

Introduction. Wear and osteolysis are major contributors which limit the durability of total hip arthroplasty (THA) and ultimately cause it to fail. Efforts were made to decrease the wear by highly cross-linked polyethylene (HXLPE) and using ceramic bearings. The purpose of this study is to analyze the five year performance of large sized (32mm and 36mm) ceramic and metal heads on X3 HXLPE (Stryker, Mahwah, NJ). Materials and Method. From Jan 2006 to June 2008, 81 consecutive patients with minimum 5 year radiographic and clinical followup were identified from out institutional prospective database. 51 non-cemented THA (45 patients) had ceramic on HXLPE (CoX3) group and 30 hips (29 patients) had metal on HXLPE (MoX3) group. Mean age was 36 ± 8 years (36–76) and 50 ± 9 years (51–86) in ceramic and metal group, respectively. Wear rates were measured on an anteroposterior weight-bearing pelvis radiographs using the computer-assisted Roman software. Results. The mean WOMAC, PAQ, HSS and UCLA scores for CoX3 and MoX3 groups at final follow-up were 13.2 ± 17.3, 10.1 ± 14.4, 36.4 ± 5.3 and 5.9 ± 1.8 and 16.5 ± 17.8, 17.1 ± 17.2, 31.6 ± 10.5 and 5.3 ± 1.6, respectively. At the final follow up, the mean wear rates were 0.022 ± 0.06 mm/yr and 0.022 ± 0.05 mm/yr for CoX3 and MoX3 groups, respectively. This was not statistically significant (p=0.8). When negative values were considered zero, wear rates for CoX3 and MoX3 groups were 0.037 ± 0.04 mm/yr and 0.033 ± 0.04 mm/yr, respectively (p=0.6). Radiographic analysis does not reveal any incidence of osteolysis or loosening in both groups. Discussion and Conclusion. The five year wear rate of large diameter metal and ceramic femoral heads on HXLPE bearing demonstrated excellent similar wear rates. Longer follow-ups are required to assess superiority of one bearing over another

Background. Highly cross-linked polyethylene (HCLPE) was introduced to reduce wear and osteolysis in total hip arthroplasty (THA). There is no reported data regarding wear rates and clinical performance of Crossfire HCLPE (Stryker, Mahwah, New Jersey) in young and active patients. The purpose of this prospective study is to assess minimum 10-year wear rates and survivorship of Crossfire in young and active patients. Material and Methods. Between January 2001 to December 2003, 52 consecutive THAs (43 patients; 26 males and 17 females), 55 years and younger, with an average University of California Los Angeles activity (UCLA) score of 7.3 ± 1.5 (5 – 10) at the time of surgery were prospectively followed. The mean age of patients was 47.4 ± 7.8 years old (range 24 to 55 years). Indication for surgery included osteoarthritis in all cases. All operations were performed by the senior surgeon via a posterolateral approach. All components were non-cemented SecurFit femoral stem, 28 mm Cobalt-Chromium (Co-Cr) femoral head, and Trident PSL cup with Crossfire HCLPE acetabular liner (Stryker, Mahwah, New Jersey). At minimum 10-years follow-up (mean 11.5 ± 0.94 years), wear rates were assessed using the Roman software. Hospital for Special Surgery (HSS) scores and survivorship data were analyzed. Results. Good to excellent clinical results were seen with HSS score of 38.1 ± 4.7. The mean linear wear was 0.019 ± 0.018 mm/year (range 0 to 0.082). There were no revisions for osteolysis or loosening, periprosthetic infection or dislocation in this cohort. Kaplan-Meier survivorship was 100% for all failures. Conclusion. This is the first study to demonstrate that metal on Crossfire performs very well with excellent survivorship and wear rates at a minimum 10-year follow-up in young and active patients. Oxidation concern with Crossfire has not caused any clinical problems up to 10 years

Introduction:. The management strategy regarding optimally addressing polyethylene wear with a well-fixed acetabular shell remains controversial. The purpose of the present study was to document outcomes of cementation of a highly cross-linked polyethylene (PE) liner into a well-fixed acetabular metal shell in 36 hips. Materials & Methods:. We identified 37 patients (39 hips) who had undergone revision THA by cementation of a highly cross-linked PE liner into a well-fixed metal shell between June 2004 and April 2009. Of these patients, one (1 hip) died before the end of the 3-year evaluation and another was lost to follow-up. Thus, the study cohort consisted of 35 patients (36 hips). There were 23 males (24 hips) and 12 female (12 hips) patients with a mean age at time of revision surgery of 57.6 years (range, 38–79 years). All operations were performed by a single surgeon using only one type of liner. Clinical and radiographic evaluation was performed at a mean of 6.1 years (range, 3–8 years) postoperatively. Results:. Mean Harris hip score improved from 58.1 (range, 39–81 points) preoperatively to 91.3 (range, 45–100 points) postoperatively (p < 0.001). Of the 36 hips, 29 (80.1%) had an excellent result, 6 (16.7%) a good result, and 1 (2.8%) a poor result. The patient with a poor clinical result had aseptic cup loosening with a greater trochanteric fracture at 2 years postoperatively and was treated by acetabular cup revision and internal fixation of the fracture. However, no case of PE liner dislodgement from the cement or of dissociation of the PE-cement construct from the metal shell was encountered. At last follow-up, no new osteolytic lesion was identified and previous osteolytic lesions filled with bone graft were completely or partially incorporated. Other complications included 1 incomplete peroneal nerve palsy and 1 dislocation. Conclusions:. The results of this study and previous reports demonstrated that cementation of highly cross-linked PE liner into well-fixed metal shell could provide good midterm durability

Background. Highly cross-linked polyethylene (HCLPE) was introduced to reduce wear and osteolysis in total hip arthroplasty (THA). There is no reported data regarding wear rates and clinical performance of Crossfire HCLPE (Stryker, Mahwah, New Jersey) in young and active patients. The purpose of this prospective study is to assess minimum 10-year wear rates and survivorship of Crossfire in young and active patients. Material and Methods. Between January 2001 to December 2003, 52 consecutive THAs (43 patients; 26 males and 17 females), 55 years and younger, with an average University of California Los Angeles activity (UCLA) score of 7.3 ± 1.5 (5 – 10) at the time of surgery were prospectively followed. The mean age of patients was 47.4 ± 7.8 years old (range 24 to 55 years). Indication for surgery included osteoarthritis in all cases. All operations were performed by the senior surgeon via a posterolateral approach. All components were non-cemented SecurFit femoral stem, 28 mm Cobalt-Chromium (Co-Cr) femoral head, and Trident PSL cup with Crossfire HCLPE acetabular liner (Stryker, Mahwah, New Jersey). At minimum 10-years follow-up (mean 11.5 ± 0.94 years), wear rates were assessed using the Roman software. Hospital for Special Surgery (HSS) scores and survivorship data were analyzed. Results. Good to excellent clinical results were seen with HSS score of 38.1 ± 4.7. The mean linear wear was 0.019 ± 0.018 mm/year (range 0 to 0.082). There were no revisions for osteolysis or loosening, periprosthetic infection or dislocation in this cohort. Kaplan-Meier survivorship was 100% for all failures. Conclusion. This is the first study to demonstrate that metal on Crossfire performs very well with excellent survivorship and wear rates at a minimum 10-year follow-up in young and active patients. Oxidation concern with Crossfire has not caused any clinical problems up to 10 years

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

Introduction. In order to reduce polyethylene wear and incidence of osteolysis, and improve the long-term durability of total hip arthroplasty (THA), highly cross-linked polyethylene was introduced for clinical use in substitution for conventional polyethylene. We performed 35 cementless THAs between December 2000 and February 2002, and cross-linked polyethylene was used in these surgeries. The purpose of this study is to research linear wear rate of these hips, and to find the risk factor for high wear rate. Patients and Methods. 32 hips (26 patients) among the 35 could be evaluated at more than 10 years postoperatively. One hip required reoperations due to infection at 8 years postoperatively, and two were lost to followup in less than 10 years. There were 2 males and 24 females, and the observation period was 11.4 years in average (range 10?13 years). The age at the time of operation was 49.4 years in average (range 24?67 years), and body mass index was 22.4 in average (15?34). We used AHFIX total hip prostheses (KYOCERA Medical Corporation) for both acetabular and femoral replacement, and 22 mm Zirconia head was used in all cases. The median cup diameter was 46 mm (range 42?50). Osteolysis and loosening of the implant was evaluated on the anteroposterior radiograph of the hip. Using software for wear measurement (Hip Analysis Suite), linear wear rate and cup inclination angle were measured. Correlation between linear wear rate and age, BMI, cup inclination angle, and cup diameter was investigated using correlation coefficient. Results. Osteolysis and loosening were not found in any cases on the final radiograph. Cup inclination angle was 44.7±4.6 degree, and linear wear rate was 0.034±0.019 mm/y in average. No statistical correlation was found between linear wear rate and age, BMI, cup inclination angle, and cup diameter. Discussion. Long-term clinical performance of cross-linked polyethylene is rarely reported, although it is considered to have excellent wear resistance, and reduces the risk of osteolysis and loosening. Linear wear rate in this series was relatively low, and osteolysis and loosening were not observed. It was demonstrated that cross-linked polyethylene had excellent wear resistance when used in combination with 22 mm zirconia head, and observed for more than 10 years

Purpose:

Although short term outcomes of reverse total shoulder arthroplasty (rTSA) have been promising, long-term success may be limited due to complications, including scapular notching. Scapular notching has been explained primarily as a mechanical erosion, however, generation of wear debris may lead to further biologic changes contributing to the severity of scapular notching. Highly cross-linked ultra-high molecular weight polyethylene (UHMWPE) has been used routinely in constrained joint applications such as total hip arthroplasty for reduction of wear debris particles. Although rTSA shares similarity in design conformity, conventional UHMWPE remains the gold standard.

Introduction:

Hard-on-hard bearings and surface replacement (SR) have been used in young and active patients due to the reduced wear and lower rates of osteolysis. However, neither of these options resulted in survivorship higher than 90%–95% in this group of patients. The purpose of this prospective study was to compare minimum 10-year survivorship of non-cemented total hip arthroplasty (THA) using 28 mm metal head against highly-cross linked polyethylene (HXLPE) in our cohort as compared to published reports of other bearings, including surface replacements, in young-active patients.

Introduction

The first highly crosslinked and melted polyethylene acetabular component for use in total hip arthroplasty was implanted in 1998 and femoral heads larger than 32mm in diameter introduced 2004.

The purpose of this study was to re-assemble a previous multi-center patient cohort in order to evaluate the radiographic and wear analysis of patients receiving this form of highly crosslinked polyethylene articulating against large diameter femoral heads at a minimum of 10 years follow-up.

Introduction

The first highly crosslinked and melted polyethylene acetabular component for use in total hip arthroplasty was implanted in 1998. Numerous publications have reported reduced wear rates and a reduction in particle induced peri-prosthetic osteolysis at short to mid-term follow-up.

The purpose of this study was to re-assemble a previous multi-center patient cohort in order to evaluate the radiographic and wear analysis of patients receiving this form of highly crosslinked polyethylene articulating against 32mm femoral heads or less at a minimum of 13 years follow-up.

Background

A first generation once annealed highly crosslinked polyethylene (HXLPE) was introduced in 1998. At 8 years it was reported to have a 78% reduction in wear compared with conventional polyethylene and no osteolysis. However, concerns regarding the long-term performance and oxidative resistance of this annealed material exist because of the presence of free radicals.

Introduction

In vitro studies showed that the anti-oxidative properties of vitamin E stabilize free radicals while retaining the mechanical strength of UHMWPE. The purpose was to evaluate vitamin E diffused polyethylene (VEPE) wear and stability of femoral components using RSA. Patient reported outcome measures (PROMs) were evaluated to determine the clinical outcome at 5 years.