Background

A few patients undergoing a total hip replacement need a subsequent revision of the cup. In some of these cases, the treating surgeon may be confronted with Unexpected Positive Intraoperative Cultures (UPIC). The exact incidence of this finding is unclear. Moreover, it is unknown what the clinical outcome of these patients is when the stem is left in situ. The aim of our study was to describe the incidence of UPIC in patients undergoing cup revision and to determine the need for total revision in this patient group during follow-up.

The aim was to identify the acetabular center, fix the acetabular implant, and reconstruct the hip rotation center using the residual Harris fossa and acetabular notch as anatomical markers during revision hip arthroplasty. Osteolysis is commonly found in the acetabulum during hip arthroplasty revision. It causes extensive defects and malformation of the anatomical structure, making correct fixation of a hip prosthesis difficult. We studied the relations of the anatomical positions between the Harris fossa and acetabular notch and the acetabular center (Fig. 1). Vertical distance from the hip rotation center to the teardrop connection and horizontal distance from the hip rotation center to the teardrop were measured on preoperative and postoperative radiographs. Vertical distance increased from 14.22±3.39 mm preoperatively to 32.64±4.51 mm postoperatively (t=3.65, P<0.05) and the horizontal distance from 25.13±3.46 mm to 32.87±4.73 mm (t=2.72, P<0.05). Altogether, 28 patients underwent revision hip arthroplasty based on the Paprosky classification for bone loss. The anatomical hip center was identified using the residual Harris fossa and acetabular notch as anatomical markers during revision hip arthroplasty. Based on these relations, we were able to place the hip prosthesis correctly. After surgery, restoration of the anatomical hip center was accomplished based on data obtained from radiographs(Fig.2 and Fig.3).

Purpose

To assess acetabular component fixation by bone ongrowth onto a titanium plasma sprayed surface as used in revision total hip arthroplasty. Acetabular bone defects, a common finding in revision surgery, and their relation to outcome were also investigated.

Hip simulator studies with ceramic-on-metal (COM) predicted less wear than metal-on-metal (MOM: Isaac. 2009). While clinical evidence is scant, two COM case reports described pseudotumors with adverse cup positioning (Deshmukh 2012, Koper 2014). It would appear that our Korean case report is the first to describe pseudotumor formation in well-positioned COM arthroplasty and including detailed failure analysis. A 50-year old female (active salesperson) had bilateral avascular necrosis of her femoral heads. A left metal-on-polyethylene (MPE) hip was performed at outside institution in 2003. At our 3-yrs evaluation, radiographs showed well-functioning MPE hip. Five years later she complained of gradual left-hip pain (2011). Radiographs and CT scan demonstrated wear, osteolysis and loosening of both components. The revision in 2011 was by COM (Fig. 1), using S-ROM stem/sleeve, 36mm ceramic head (Biolox-delta), a CoCr liner and 54mm shell (Pinnacle: Depuy Inc). Cup inclination and anteversion were considered appropriate at 45° and 20° respectively; femoral anteversion of 15° was also appropriate.

At 1-yr follow-up patient complained of mild discomfort in left COM hip (2012). Range of motion was painless and normal. Examination revealed a soft, non-tender swelling (2×3cm) in left inguinal region with no inflammation and radiographs were normal (Fig. 1a). One month later the patient complained of left hip pain, the previously noted swelling had increased in size, and she started to limp. Radiographs showed cup migration with increased inclination. CT scans showed a circumscribed lesion extending into iliopsoas region (Fig 2). Serum cobalt and chromium levels were high at 2.4 and 22.5µg/ L, respectively.

At revision the pseudotumor and surrounding inflamed synovium was excised. The cystic soft-tissue swelling (stained black) extended into the joint (Fig. 2a). The ceramic head showed a large “black stripe” across the dome (Fig 2b). The cup was loose while the femoral stem was well fixed. Operative cultures of soft tissues and joint fluid were negative for infection while histopathology was consistent for metallosis (Fig. 3). Aggressive debridement was carried out, acetabular defects were filled with bone graft. Revision incorporated 32mm ceramic head (Biolox-delta), highly cross-linked liner and 52mm trabecular-metal shell (Depuy). Functionally the patient has continued to improve. By 6 months, serum ion concentrations decreased to Co:1.3 and Cr:2.54µg/ L with most recent ion levels lower still (Co:0.66 and Cr:0.42µg/ L).

Ceramic head surfaces showed normal wear appearance. The large gray stripe identified on the highly polished dome contained Co and Cr metal-transfer from the CoCr liner (Fig. 2b). Thin gray stripes on equatorial head regions (x4 rougher than dome) represented contamination by Ti, Al and V, typical of adverse impingement against Ti6Al4V neck (Clarke 2013). There was a 100–150um defect on rim of CoCr liner as a result of impingement. Cup out-of-roundness was 476um compared to only 7um for ceramic head, thus cup wear dominated at 25–30mm³ volume. This case report was illustrative of the unpredictable and seldom diagnosed risk of habitual cup-to-neck impingement and the risk of relying on pristine simulator studies to predict outcomes in novel THA bearings.

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Aim

Very limited information is available regarding health-related quality of life (HRQOL) and patient reported hip function following treatment for chronic periprosthetic hip joint infection (PJI). Several reviews have not found any clear differences in clinical outcome parameters comparing the most commonly applied treatment strategies for chronic hip PJI. Studies describing patients HRQOL of one-stage and two-stage revision could provide important information regarding patient counselling. The purpose of this study was to investigate HRQOL and patient reported hip function after one-stage revision and two-stage revision in chronic hip PJI.

Total hip arthroplasty (THA) is an effective treatment for symptomatic hip osteoarthritis (OA). Computer-navigation technologies in total knee arthroplasty show evidence-supported survivorship advantages and are used widely. The aim of this study was to determine the revision outcome of hip commercially available navigation technologies.

Data from the Australian Orthopaedic Association National Joint Replacement Registry from January 2016 to December 2020 included all primary THA procedures performed for osteoarthritis (OA). Procedures using the Intellijoint HIP® navigation were identified and compared to procedures inserted using ‘other’ computer navigation systems and to all non-navigated procedures. The cumulative percent revision (CPR) was compared between the three groups using Kaplan-Meier estimates of survivorship and hazard ratios (HR) from Cox proportional hazards models, adjusted for age and gender. A prosthesis specific analysis was also performed.

There were 1911 procedures that used the Intellijoint® system, 4081 used ‘other’ computer navigation, and 160,661 were non-navigated. The all-cause 2-year CPR rate for the Intellijoint HIP® system was 1.8% (95% CI 1.2, 2.6), compared to 2.2% (95% CI 1.8, 2.8) for other navigated and 2.2% (95% CI 2.1, 2.3) for non-navigated cases. A prosthesis specific analysis identified the Paragon/Acetabular Shell THAs combined with the Intellijoint HIP® system as having a higher (3.4%) rate of revision than non-navigated THAs (HR = 2.00 (1.01, 4.00), p=0.048).

When this outlier combination was excluded, the Intellijoint® system group demonstrated a two-year CPR of 1.3%. There was no statistical difference in the CPR between the three groups before or after excluding Paragon/Acetabular Shell system.

The preliminary data presented demonstrate no statistical difference in all cause revision rates when comparing the Intellijoint HIP® THA navigation system with ‘other’ navigation systems and ‘non-navigated’ approaches for primary THAs performed for OA. The current sample size remains too small to permit meaningful subgroup statistical comparisons.

Introduction

Periprosthetic joint infection (PJI) is a serious problem and requires great effort and cost for its treatment. Treatment options may vary from resection arthroplasty, retention of prosthesis with debridement, one stage revision and two stage revision with handmade antibiotic impregnated cement spacer or with prefabricated antibiotic loaded cement spacer. Two stage revision remains the gold standard for the treatment of periprosthetic joint infection after Total Hip Arthroplasty (THA). This study was aimed to find the efficacy and cost effectiveness of handmade antibiotic impregnated articulating cement spacer over commercially available prefabricated antibiotic loaded cement spacer for the treatment of deep PJI of hip prosthesis and to evaluate its functional outcome.

Removal of well-fixed cement at the time of revision THA for sepsis is time consuming and risks bone stock loss, femoral perforation or fracture. We report our experience of two-stage revision for infection in a series of cases in which we have retained well-fixed femoral cement.

All patients underwent two-stage revision for infection. At the first stage the prostheses and acetabular cement were removed but when the femoral cement mantle demonstrated good osseo-integration it was left in-situ. Following Girdlestone excision arthroplasty (GEA), patients received local antibiotics delivered by cement spacers, as well as systemic antibiotics. At the second stage the existing cement mantle was reamed, washed and dried and then a femoral component was cemented into the old mantle.

Sixteen patients (M:F 5:11) had at least three years follow-up (mean 80 months – range 43 to 91). One patient died of an unrelated cause at 53 months. Recurrence of infection was not suspected in this case. The mean time to first stage revision was 57 months (3 to 155). The mean time between first and second stages was nine months (1 to 35). Organisms were identified in 14 (87.5%) cases (5 Staphylococcus Aureas, 4 Group B Streptococcus, 2 Coagulase negative Staphylococcus, 2 Enterococcus Faecalis, 1 Escheria Coli). At second stage, five (31.2%) acetabulae were uncemented and 11 (68.8%) were cemented. There were two complications; one patient dislocated 41 days post-operatively and a second patient required an acetabular revision at 44 days for failure of fixation. No evidence of infection was found at re-revision. One patient (1/16, 7%) has been re-revised for recurrent infection. Currently no other patients are suspected of having a recurrence of infection (93%).

Retention of a well-fixed femoral cement mantle during two-stage revision for infection and subsequent cement-in-cement reconstruction appears safe with a success rate of 93%. Advantages include a shorter operating time, reduced loss of bone stock, improved component fixation and a technically easier second stage procedure.

The aim of our review was to assess (health related) quality of life ((HR)QoL) after one-stage or two-stage revision for prosthetic joint infection (PJI). Although it is generally accepted that staged revisions are very strenuous for patients, little is known about the (HR)QoL after these procedures. We compared (HR)QoL scores with normative population scores to assess the magnitude of this problem.

Two authors performed a computerized systematic search in Embase, Cochrane and Pubmed. We included articles that reported: validated (HR)QoL questionnaires, one-stage or two-stage revision for PJI after total hip arthroplasty (THA), a minimum follow-up of 24 months and a minimum of ten patients. Methodological quality of all papers was assessed using the MINORS score. The systematic review was conducted according to the PRISMA statement.

The search produced 11195 hits. After selection, based on title and abstract, 18 full text papers were reviewed. Six articles were excluded. Twelve papers were selected for final assessment. All papers described two-stage revisions. The mean MINORS score for these studies was 9.8, indicating moderate study quality.

Seven articles reported WOMAC scores, with a total of 185 patients (74% response rate) having a mean general score of 73, with a mean follow-up of 65 months. The normative total WOMAC score for the general population (age 60–64) is 82.9, with a score of 100 being the best possible outcome.

Four articles described Short Form 36 (SF-36) results on a total of 159 patients (71.9% response rate). In these studies the physical component score (PCS) of the SF-36 was on average 39.6 and the mental component score (MCS) was on average 50.9, with a mean follow-up of 41 months. Normative data for the US population (age 55–64) are a PCS of 47.2 and an MCS of 51.8.

Four articles reported Short Form 12 (SF-12) scores on a total of 138 patients, with a mean PCS of 33.6 and a mean MCS of 51.7, with a mean follow up of 72.5 months. Normative data for the Dutch population (age 55–65) are a PCS of 48.3 and an MCS of 52.8. A score of 100 represents best possible health for both SF questionnaires.

Patients that underwent two-stage revision for hip PJI have substantially lower (physical component) (HR)QoL scores, when compared to the general population.

Soft tissue reactions following metal-on-metal arthroplasty of the hip have been under discussion in recent times. The phenomenon has been observed since the advent of arthroplasty, but the particular nature of metal-on-metal (MoM) resurfacing or total hip arthroplasty (THA), and the associated shedding of metal particles in high wear states, appears to excite a more aggressive response. Recent reports suggest involvement of muscle groups on a wide scale, and some cases of neurovascular involvement. It is not known which reactions require widespread muscle excision, and which cases may be adequately addressed by bearing exchange alone. We report three cases of soft tissue reaction (pseudotumour) following MoM hip resurfacing all managed with revision to ceramic-on-ceramic (CoC) THA with minimal soft tissue excision. All patients were female with ages at original operation of 49, 52 and 58 years. Time to revision surgery was 85, 28 and 66 months respectively.

Prosthesis revision resulted in progressive and satisfactory resolution of the pseudotumour. We propose that in the early stages, pseudotumour following MoM hip resurfacing can be adequately managed with revision to ceramic-bearing THA with minimal soft tissue excision, rather than revision with extensive soft tissue debridement that has been recently described.

Revision is a key negative outcome of joint replacements. The purpose of this abstract is to present revision risk curves for hip and knee replacements based on the most recently available national data sources. Having a better understanding of determinants of revision risk can help inform clinical and health care system improvements. We explored revision risk of primary joint replacement stratified by key clinical, prosthesis, and surgeon-level factors using data from three databases managed by CIHI: the Canadian Joint Replacement Registry (CJRR), the Discharge Abstract Database, and the National Ambulatory Care Reporting System. To investigate early revisions, we used Kaplan-Meier analysis stratified by demographic factors to determine the risk of revision within up to five years of primary surgery. This analysis identified the primary cohort from the CJRR from April 1, 2012 to March 31, 2017 and was limited to mandatory reporting provinces (British Columbia, Manitoba and Ontario) to ensure maximal coverage of prosthesis information. Bearing surface was obtained from the International Prosthesis Library maintained by the International Consortium of Orthopaedic Registries (ICOR) and the International Society of Arthroplasty Registers (ISAR). The total revision risk cohort contained 283,620 primary surgeries, of which 5,765 (2%) had at least one revision. For total hip arthroplasties, revision risk at the end of the follow-up period did not differ by age, by sex or across bearing surface (metal on cross-linked polyethylene [XLPE], ceramic on XLPE, ceramic on ceramic, metal on non-cross-linked polyethylene). For hemiarthroplasties in hip fracture patients, cement fixation was significantly associated with decreased revision risk. Surgeon volume had a positive effect on survivorship with cementless fixation (2.7% at one year [95% CI 2.3%, 3.1%] for high-volume vs 3.2% [2.7%, 3.7%] for low-volume). However, surgeon volume did not have an effect on survivorship with cemented fixation (2% at one year [95% CI 1.3%, 2.6%] for high-volume vs. 2% [1.4%, 2.6%] for low-volume). For total knee replacements, revision risk increased with decreasing age and male sex. For patients aged 75 and older, four-year revision risks were 1.5% (95% CI 1.3%, 1.7%) for women and 2.0% (1.7%, 2.3%) for men, but for patients under 55 years old, they were 4.3% (3.7%, 5%) for women and 5.9% (4.9%, 6.9%) for men. Additional results from the upcoming 2019 CJRR annual report, including data up to March 31, 2018, will be presented. Revisions represent a key failure of the primary replacement, they are costly to the health care system and negatively affect patients' quality of life. CJRR's coverage is currently 72%, increased coverage and follow-up time will allow increasingly comprehensive reporting on hip and knee prostheses in Canada. Future work in this area involves exploring additional prosthesis attributes for stratification of revision risk curves and calculation of hazards ratios adjusted by age and sex

Aim. Aseptic loosening is the leading cause of revision of total hip arthroplasty (THA). It is well recognized that an occult infection is the underlying cause of some aseptic revisions. Intraoperative cultures are central to the diagnosis of prosthetic joint infection (PJI). However, the diagnostic and prognostic value of unexpected positive intraoperative cultures remains unclear. The aim was to study whether first-time aseptic revision of a total hip arthroplasty with unexpected bacterial growth in cultures of intraoperatively taken biopsies have an increased risk of secondary revision due to all causes and increased risk of PJI revision, specifically. Method. Cases reported as first-time aseptic loosening revisions to the Danish Hip Arthroplasty Register (DHR) performed during January 1. st. , 2010, to May 15. th. , 2016, were included. DHR data were merged with the Danish Microbiology Database, which contains data from all intraoperatively obtained cultures in Denmark. Included first-time revisions were grouped based on the number of positive cultures growing the same bacteria genus: ≥2, 1 and 0 cultures. Revisions were followed until secondary revision, death, or end of follow-up period after one year. Relative risk for secondary revision due to all causes and PJI was estimated. Results. We included 2,305 first-time aseptic revisions. Unexpected growth was found in 282 (12%) of which 170 (60%) cases showed growth of the same bacteria in only one culture. Coagulase-negative staphylococcus accounted for 121 (71%). Secondary revision was performed in 163 (7%) cases, with PJI being the indication for revision in 43 (26%) cases. The relative risk of secondary revision was significantly higher for cases of one positive culture growing the same bacteria compared to culture negative cases, both for revision due to all causes; 1.73 (95%CI 1.07; 2.80) and PJI exclusively; 2.63 (1.16; 5.96). Cases of 2 or more biopsies culturing the same bacteria had a relative risk of all cause revision of 1.52 (0.82; 2.80). Conclusions. First-time aseptic loosening THA revisions with unexpected growth in only one biopsy culture had an increased risk of secondary revision, both due to all causes and PJI. Our findings indicate that some cases of unexpected growth of bacteria should likely be regarded as clinically significant and not sample contamination, underlining the need for more awareness and better strategies when treating patients with unexpected positive intraoperative cultures. The improved diagnosis of occult PJI in clinically aseptic THA is of great importance for future care of this large and growing patient group

Introduction. Acetabular component loosening has been one of the factors of revision of total hip arthroplasty (THA). Inadequate mechanical fixation or load transfer may contribute to this loosening process. Several reports showed the load transfer in the acetabulum by metal components. However, there is no report about the influence of the joint surface on the load transfer. We developed a novel acetabular cross-linked polyethylene (CLPE) liner with graft biocompatible phospholipid polymer(MPC) on the surface. The MPC polymer surface had high lubricity and low friction. We hypothesized the acetabular component with MPC polymer surface (MPC-CLPE) may reduce load transfer in the acetabulum compared to that of the by CLPE acetabular component without MPC. Methods. We fixed the three cement cup with MPC-CLPE (Group M; sample No.1–3) and three cement cup with CLPE (Group C; sample No.4–6) placed in the synthetic bone block with bone cement with a 0.10mm thick arc-shaped piezoresistive force sensor, which can measure the dynamic load transfer(Tekscan K-scan 4400; Boston). (Fig 1) A hip simulator (MTS Systems Corp., Eden Prairie, MN) was used for the load transfer test performed according to the ISO Standard 14242-1. Both groups had same inner and outer diameter s of 28 and 50mm, respectively. A Co–Cr alloy femoral head with a diameter of 28 mm (K-MAXs HH-02; KYOCERA Medical Corp.) was used as the femoral component. A biaxial rocking motion was applied to the head/cup interface via an offset bearing assembly with an inclined angle of +20. Both the loading and motion were synchronized at 1 Hz. According to the double-peaked Paul-type physiologic hip load, the applied peak loads were 1793 and 2744 N described in a previous study. The simulator was run 3 cycles. We recorded both the peak of the contact force and the accumulation of the six times load in total. Secondly, we calculated the mean change of the load transfer. We used the Student t-test. P value < 0.05 was used to determine statistical significance. We used EZR for statistical analysis. Results. The mean of total accumulation of the load transfer in the group M is significantly lower than that of in the group C. (7037±508 N vs 11019±1290 N, P<0.0001). The peak of load in the group M was also significantly lower than that in the group C. (1024±166 N vs 1557±395 N) (Fig 2)The mean of the change of the load transfer in the group M is significantly lower than that of in the group C. (2913±112 N vs 4182±306 N) (Fig 3). Conclusion. The acetabular component with MPC surface could reduce and prevent the radical load transfer change toward to the acetabulum compared to CLPE acetabular component without MPC. For any figures or tables, please contact the authors directly

Orthopaedic implants, such as femoral heads, sockets and stems, are manufactured with a high degree of smoothness and very low form error in order to function as low wear bearings. The surfaces are subject to both wear and damage during in vivo use. Articulating surfaces naturally wear during normal use. Aseptic loosening associated with osteolysis and release of wear particles is the main reason for revision of total hip arthroplasty (THA). Damage of femoral heads is well known to increase the wear rate at the articulating surface and is vulnerable to scratching during the maneuver of positioning the femoral component into the acetabulum component either in primary as in revision total hip arthroplasties. The findings emphasize the importance of achieving and maintaining good surface finish of the femoral head component. The author presents a very simple and “zero cost” method of preventing scratching of the femoral head of any kind of total hip prosthesis (ceramic on ceramic, ceramic on poly, metal on metal, metal on poly and even metal on ceramic) when the reduction of the femoral head prosthesis is done inside the new acetabular component with metal, ceramic liner or poly liner with metal back (where the scratching can also occur) as one of the final stages of the surgical procedure which can be crucial to the long survival of the hip prosthesis. A short one minute video on an e-poster will show how this can be done being an easy, reproducible, safe and reliable technique to prevent femoral head scratching

Instability is the most common reason for revision after total hip arthroplasty (THA). Since THA requires arthrotomy of the hip and replacement with a femoral head that is smaller than the normal hip, instability following THA is always a potential concern. Many factors contribute to the development of instability after THA including: restoration of normal anatomy, implant design, component position, surgical approach and technique, and numerous patient related factors. Recently, the role of spinal mobility and deformity has been shown to have a significant effect on risk of dislocation after THA. The long held guidelines for component positioning or so called “safe zone” described by Lewinnek have also been questioned since most dislocations have been shown to occur in patients whose components are positioned within this “safe” range. In the early post-operative period, dislocation can occur prior to capsular and soft tissue healing if the patient exceeds their peri-operative range of motion limits. Closed reduction and abduction bracing for 6 weeks may allow for soft tissue healing and stabilization of the hip. It is important to try and identify the mechanism of dislocation since this can affect the technique of closed reduction, how the patient is braced following reduction and what may need to be addressed at the time of revision if dislocation recurs. Closed reduction and bracing may be effective in patients who have a previously well-functioning, stable THA who suffer a traumatic dislocation after the peri-operative period. Despite successful closed reduction, recurrent dislocation occurs in many patients and can be secondary to inadequate soft tissue healing, patient noncompliance or problems related to component positioning. Patients who incur more than 2 dislocations should be considered for revision surgery. Prior to revision surgery, an appropriate radiographic evaluation of the hip should be performed to identify any potential mechanical/kinematic issues that need to be addressed at the time of revision. Typically this involves plain radiographs, including a cross table lateral of the involved hip to assess acetabular version, but may also involve cross-sectional imaging to assess femoral version. Patients with soft tissue pseudotumors frequently have significant soft tissue deficiencies that are not amenable to component repositioning alone and require use of constrained or dual mobility components. In general, “limited revisions” consisting of modular head and liner exchange with insertion of a lipped liner and larger, longer femoral head rarely correct the problem of recurrent instability, since component malposition that frequently contributes to the instability is not addressed. Similarly, insertion of a constrained liner in a malpositioned cup is associated with a high rate of implant failure and recurrent dislocation since impingement contributing to the instability is not addressed. In patients who fail closed management and have a history of recurrent instability, we have found the treatment paradigm described by Wera, et al. to be very helpful in the management of the unstable THA. Several studies have shown that tripolar type constrained liners appear to perform considerably better than locking ring type constrained liners. As a result, dual mobility implants are becoming more widely utilised in patients with abductor and other soft tissue deficiencies, hip instability of uncertain etiology and patients with increased risk factors for instability undergoing primary THA. Early results with dual mobility components have been shown to have a low rate of failure in high instability risk revision THAs. These devices do have several unique potential complications and their use should be limited to patients with significantly increased risk of dislocation and instability

Revision of total hip arthroplasty (THA) is being performed with increasing frequency. However, outcomes of repeated revisions have been rarely reported in the literature, especially for severe defects. Cup revision can be a highly complex operation depending on the bone defect. In acetabular defects like Paprosky types 1 and 2 porous cementless cups maybe fixed with screws give good results. Modern trabecular metal designs improve these good results. Allografts are useful for filling cavitary defects. In acetabular defects Paprosky types 3A and 3B, impacted morselised allografts with a cemented cup technique produce good results. Difficult cases with pelvic discontinuity require reconstruction of the acetabulum with acetabular plates or large cup-cages to solve these difficult problems. However, there is still no consensus regarding the best option for reconstructing hips with bone loss. Although the introduction of ultraporous metals has significantly increased the surgeon's ability to reconstruct severely compromised hips, there remain some that cannot be managed readily using cups, augments, or cages. In such situations custom acetabular components may be required. Individual implants represent yet another tool for the reconstructive surgeon. These devices can be helpful in situations of catastrophic bone loss. Ensuring long-term outcome mechanical stability has a greater impact than restoring an ideal center of rotation. We have done so far 15 3D Printed Individual Implants. All of them where Paprosky Type 3B defects, 10 with a additional pelvis discontinuity. The mean follow-up is 18 months. All implanted devices are still in place, no infection, no loosening. However, despite our consecutive case series, there are no mid- to long-term results available so far. Re-revision for failed revision THA acetabular components is a technically very challenging condition. The 3D Printed Individual Implants have a lot of advantages, like excellent surgical planning and a very simple technique (operative time, blood loss, instruments). They are a very stable construct for extensive acetabular defects and pelvic discontinuity

Revision of total hip arthroplasty (THA) is being performed with increasing frequency. However, outcomes of repeated revisions have been rarely reported in the literature, especially for severe defects. Cup revision can be a highly complex operation depending on the bone defect. In acetabular defects like Paprosky types 1 and 2 porous cementless cups fixed with screws give good results. Modern trabecular metal designs improve these good results. Allografts are useful for filling cavitary defects. In acetabular defects Paprosky types 3A and 3B, especially the use of trabecular metal cups, wedges, buttresses and cup-cage systems can produce good results. Difficult cases in combination with pelvic discontinuity require reconstruction of the acetabulum with acetabular plates or large cup-cages to solve these difficult problems. However, there is still no consensus regarding the best option for reconstructing hips with bone loss. Although the introduction of ultraporous metals has significantly increased the surgeon's ability to reconstruct severely compromised hips, there remain some that cannot be managed readily using cups, augments, or cages. In such situations custom acetabular components may be required. Individual implants represent yet another tool for the reconstructive surgeon. These devices can be helpful in situations of catastrophic bone loss. Ensuring long-term outcome, mechanical stability has a greater impact than restoring an ideal center of rotation. However, despite our consecutive case series there are no mid- to long-term results available so far. Re-revision for failed revision THA acetabular components is a technically very challenging condition

Infection remains a serious complication of total hip replacement (THR). Management options have been developed to improve clearance of infection while maintaining joint function during treatment and improve outcome at reimplantation. The gold standard in management is generally considered to be implant removal and thorough debridement with antibiotic therapy delivered systemically and locally with impregnated spacers. However, some surgeons still prefer to use Girdlestone resection arthroplasty, thus not leaving any foreign body in situ. The aim of this study was to compare infection clearance rates, radiographic and functional outcomes after two-stage revision of total hip arthroplasty with (1) gentamicin-loaded bone cement spacer or (2) Girdlestone resection arthroplasty as the first stage of treatment. We retrospectively reviewed data of 48 patients (20 females, 28 males) with implanted spacers and 53 patients (21 females, 32 males) treated with resection arthroplasty at tertiary care university hospital in the years 2008–2012. Minimum follow-up was three years (range, 3–7 years). Treatment choice was at the operating surgeons's discretion. In the spacer group, mean age at the time of first stage was 62 years (range 24–79 years), time from primary replacement 14 months, and the time from the first to the second stage of the revision 7 months. At latest, minimum 3-year follow-up, two were still ambulating with a spacer in situ, and five were re-revised with another spacer before the reimplantation of the THR. In the resection arthroplasty group, mean age at the time of first stage was 64 years (range, 37–87 years), time from primary replacement 13 months, and the time from the first to the second stage of revision − 10 months. At the latest follow-up, four patients were ambulating with resection arthroplasty, one did not clear his infection and one died of unrelated causes. The cure ratio appeared to be the same within both groups (Fisher exact test, p=0.08). Patients with spacers achieved better functional results, used less supports for ambulation and had less leg length discrepancy after the second stage of revision. In the light of those results, we cannot recommend for the use of resection arthroplasty in the treatment of the infected THR

INTRODUCTION. Patients less than 60 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. For the six year period from May 1999 to March 2005, 278 hip replacements in 244 patients less than 60 yeas of age at the time of surgery were performed using alumina ceramic-ceramic bearings. All hips had uncemented titanium femoral and acetabular components. The ceramic liner was fixed to the shell with an 18-degree flush-mounted taper design. Patients were followed clinically and radiographically. Attempts were made to contact all patients who had not been seen in the prior 3 years. Of the 278 hips, 17 hips (16 patients) remain lost to follow-up, leaving 261 hips (228 patients; 155 hips in men, 106 hips in women) for assessment. Mean age of the patients was 46.2 years at the time of surgery (range 17.8 to 59.9 years). 17% of hips had at least one previous hip surgery. Mean time following surgery was 9.75 years (range 2 to 16.8 years). RESULTS. At mean 9.75 year follow-up, none of these 261 hips experienced early or late deep infection or dislocation. Four patients died of causes unrelated to their arthroplasty at a mean of 6.1 years, all with well functioning constructs. Nine hips (3%) were revised: 2 stems and 2 cups failed to osseointegrate; 1 modular neck component sustained a modular neck fracture; and ceramic fracture occurred in 1 femoral head and 3 liners. Three of the 4 patients with fracture sustained severe trauma from life-threatening injuries. CONCLUSION. Total hip arthroplasty in young patients demonstrates excellent survivorship when uncemented titanium implants are coupled with ceramic-ceramic bearings

Highly crosslinked polyethylene (XLPE) was introduced to decrease peri-prosthetic osteolysis related to polyethylene wear, a major reason for revision of total hip arthroplasty. There are few reports of wear and osteolysis at 10 years post-operatively. We asked the following questions: (1) What are the linear and volumetric wear rates of one remelted XLPE at 10–14 years using the Martell method? (2) What is the relationship between volumetric wear, femoral head size, and osteolysis? (3) What is the incidence of osteolysis using conventional radiographs with Judet views and the Martell method?. Methods We evaluated a previously reported cohort of 84 hips (72 patients) with one design of an uncemented acetabular component and one electron-beam irradiated, remelted XLPE at a mean follow-up of 11 years (range 10 to 14 years). Measurements of linear and volumetric wear were performed in one experienced laboratory by the Martell method and standard radiographs, with additional Judet views, were used to detect peri-prosthetic osteolysis. Statistical analysis of wear and osteolysis compared to head size was performed. Results The mean linear wear rate by the first-to-last method was 0.024 mm/year (median, 0.010 mm/year) and the mean volumetric wear rate by this method was 12.2 mm. 3. /year (median, 3.6 mm. 3. /year). We found no association between femoral head size and linear wear rate. However, there was a significant relationship between femoral head size and volumetric wear rates, with 36/40 mm femoral heads having significantly higher volumetric wear (p=0.02). Small osteolytic lesions were noted in 12 hips (14%), but there was no association with head size, acetabular component position, or linear or volumetric wear rates. Conclusion This uncemented acetabular component and this particular remelted XLPE had low rates of linear and volumetric wear. Small osteolytic lesions were noted at 10 to 14 years, but were not related to femoral head size, linear or volumetric wear rates