There is widespread concern regarding the incidence of adverse soft-tissue reactions after metal-on-metal (MoM) hip replacement. Recent National Joint Registry data have shown clear differences in the rates of failure of different designs of hip resurfacing. Our aim was to update the failure rates related to metal debris for the Articular Surface Replacement (ASR). A total of 505 of these were implanted. Kaplan-Meier analysis showed a failure rate of 25% at six years for the ASR resurfacing and of 48.8% for the ASR total hip replacement (THR). Of 257 patients with a minimum follow-up of two years, 67 (26.1%) had a serum cobalt concentration which was greater than 7 μg/l. Co-ordinate measuring machine analysis of revised components showed that all patients suffering adverse tissue reactions in the resurfacing group had abnormal wear of the bearing surfaces. Six THR patients had relatively low rates of articular wear, but were found to have considerable damage at the trunion-taper interface. Our results suggest that wear at the modular junction is an important factor in the development of adverse tissue reactions after implantation of a large-diameter MoM THR

We present the results for 4762 revision total hip arthroplasties with no previous infection in the hip, which were reported to the Norwegian Arthroplasty Register between 1987 and 2003. The ten-year failure rate for revised prostheses was 26% (95% CI 25 to 26). Cox regression analyses were undertaken separately for acetabular and femoral revision components. Cemented revision components without allograft was the reference category. For acetabular components, we found a significantly reduced risk of failure for uncemented revisions both with (relative risk (RR) = 0.66; 95% CI 0.43 to 0.99) and without (RR = 0.37; 95% CI 0.22 to 0.61) allograft. For femoral components, we found a significantly reduced risk of failure for uncemented revisions, both with (RR = 0.27; 95% CI 0.16 to 0.46) and without (RR = 0.22; 95% CI 0.11 to 0.46) unimpacted allograft. This reduced risk of failure also applied to cemented revision components with allograft (RR = 0.53; 95% CI 0.33 to 0.84) and with impaction bone grafting (RR = 0.34; 95% CI 0.19 to 0.62). Revision prostheses have generally inferior results when compared with primary prostheses. Recementation without allograft, and uncemented revision with bone impaction, were associated with worse results than the other revision techniques which we studied

This study reports the mid-term results of a large-bearing hybrid metal-on-metal total hip replacement in 199 hips (185 patients) with a mean follow-up of 62 months (32 to 83). Two patients died of unrelated causes and 13 were lost to follow-up. In all, 17 hips (8.5%) have undergone revision, and a further 14 are awaiting surgery. All revisions were symptomatic. Of the revision cases, 14 hips showed evidence of adverse reactions to metal debris. The patients revised or awaiting revision had significantly higher whole blood cobalt ion levels (p = 0.001), but no significant difference in acetabular component size or position compared with the unrevised patients. Wear analysis (n = 5) showed increased wear at the trunnion-head interface, normal levels of wear at the articulating surfaces and evidence of corrosion on the surface of the stem. The cumulative survival rate, with revision for any reason, was 92.4% (95% confidence interval 87.4 to 95.4) at five years. Including those awaiting surgery, the revision rate would be 15.1% with a cumulative survival at five years of 89.6% (95% confidence interval 83.9 to 93.4). This hybrid metal-on-metal total hip replacement series has shown an unacceptably high rate of failure, with evidence of high wear at the trunnion-head interface and passive corrosion of the stem surface. This raises concerns about the use of large heads on conventional 12/14 tapers

Aims. The risk of mechanical failure of modular revision hip stems is frequently mentioned in the literature, but little is currently known about the actual clinical failure rates of this type of prosthesis. The current retrospective long-term analysis examines the distal and modular failure patterns of the Prevision hip stem from 18 years of clinical use. A design improvement of the modular taper was introduced in 2008, and the data could also be used to compare the original and the current design of the modular connection. Methods. We performed an analysis of the Prevision modular hip stem using the manufacturer’s vigilance database and investigated different mechanical failure patterns of the hip stem from January 2004 to December 2022. Results. Two mechanical failure patterns were identified: fractures in the area of the distal fluted profile (distal stem fracture) and failure of the modular taper (modular fracture). A failure rate of 0.07% was observed for distal stem fracture, and modular fracture rates of 1.74% for the original and 0.013% for the current taper design. Conclusion. A low risk of mechanical failure for both fracture types was observed compared to other known complications in revision hip arthroplasty. In addition, the data show that a design change did significantly reduce the risk of a modular fracture. Cite this article: Bone Joint J 2024;106-B(2):151–157

Aims. Total hip arthroplasty (THA) is considered the preferred treatment for displaced proximal femoral neck fractures. However, in many countries this option is economically unviable. To improve outcomes in financially disadvantaged populations, we studied the technique of concomitant valgus hip osteotomy and operative fixation (VOOF). This prospective serial study compares two treatment groups: VOOF versus operative fixation alone with cannulated compression screws (CCSs). Methods. In the first series, 98 hip fixation procedures were performed using CCS. After fluoroscopic reduction of the fracture, three CCSs were placed. In the second series, 105 VOOF procedures were performed using a closing wedge intertrochanteric osteotomy with a compression lag screw and lateral femoral plate. The alignment goal was to create a modified Pauwel’s fracture angle of 30°. After fluoroscopic reduction of fracture, lag screw was placed to achieve the calculated correction angle, followed by inter-trochanteric osteotomy and placement of barrel plate. Patients were followed for a minimum of two years. Results. Mean follow-up was 4.6 years (4.1 to 5.0) in the CCS group and 5.5 years (5.25 to 5.75) in the VOOF group. The mean Harris Hip Score at two-year follow-up was 83.85 in the CCS group versus 88.00 in the VOOF group (p < 0.001). At the latest follow-up, all-cause failure rate was 29.1% in the CCS group and 11.7% in the VOOF group (p = 0.003). The total cost of the VOOF technique was 7.2% of a THA, and total cost of the CCS technique was 6.3% of a THA. Conclusion. The VOOF technique decreased all-cause failure rate compared to CCS. The total cost of VOOF was 13.5% greater than CCS, but 92.8% less than a THA. Increased cost of VOOF was considered acceptable to all patients in this series. VOOF technique provides a reasonable alternative to THA in patients who cannot afford a THA procedure. Cite this article: Bone Jt Open 2023;4(5):329–337

Aims. Two-stage exchange revision total hip arthroplasty (THA) performed in case of periprosthetic joint infection (PJI) has been considered for many years as being the gold standard for the treatment of chronic infection. However, over the past decade, there have been concerns about its safety and its effectiveness. The purposes of our study were to investigate our practice, collecting the overall spacer complications, and then to analyze their risk factors. Methods. We retrospectively included 125 patients with chronic hip PJI who underwent a staged THA revision performed between January 2013 and December 2019. All spacer complications were systematically collected, and risk factors were analyzed. Statistical evaluations were performed using the Student's t-test, Mann-Whitney U test, and Fisher's exact test. Results. Our staged exchange practice shows poor results, which means a 42% mechanical spacer failure rate, and a 20% recurrent infection rate over the two years average follow-up period. Moreover, we found a high rate of spacer dislocation (23%) and a low rate of spacer fracture (8%) compared to the previous literature. Our findings stress that the majority of spacer complications and failures is reflecting a population with high comorbid burden, highlighted by the American Society of Anesthesiology grade, Charlson Comorbidity Index, and Lee score associations, as well as the cardiac, pulmonary, kidney, or hepatic chronic conditions. Conclusion. Our experience of a two-stage hip exchange revision noted important complication rates associated with high failure rates of polymethylmethacrylate spacers. These findings must be interpreted in the light of the patient’s comorbidity profiles, as the elective population for staged exchange has an increasing comorbid burden leading to poor results. In order to provide better results for this specific population, our conclusion suggests that comparative strategy studies are required to improve our therapeutic indication. Cite this article: Bone Jt Open 2022;3(6):485–494

Aims. Hip resurfacing remains a potentially valuable surgical procedure for appropriately-selected patients with optimised implant choices. However, concern regarding high early failure rates continues to undermine confidence in use. A large contributor to failure is adverse local tissue reactions around metal-on-metal (MoM) bearing surfaces. Such phenomena have been well-explored around MoM total hip arthroplasties, but comparable data in equivalent hip resurfacing procedures is lacking. In order to define genetic predisposition, we performed a case-control study investigating the role of human leucocyte antigen (HLA) genotype in the development of pseudotumours around MoM hip resurfacings. Methods. A matched case-control study was performed using the prospectively-collected database at the host institution. In all, 16 MoM hip resurfacing 'cases' were identified as having symptomatic periprosthetic pseudotumours on preoperative metal artefact reduction sequence (MARS) MRI, and were subsequently histologically confirmed as high-grade aseptic lymphocyte-dominated vasculitis-associated lesions (ALVALs) at revision surgery. ‘Controls’ were matched by implant type in the absence of evidence of pseudotumour. Blood samples from all cases and controls were collected prospectively for high resolution genetic a nalysis targeting 11 separate HLA loci. Statistical significance was set at 0.10 a priori to determine the association between HLA genotype and pseudotumour formation, given the small sample size. Results. Using a previously-reported ALVAL classification, the majority of pseudotumour-positive caseswere found to have intermediate-grade group 2 (n = 10; 63%) or group 3 (n = 4; 25%) histological findings. Two further patients (13%) had high-grade group 4 lesions. HLA-DQB1*05:03:01 (p = 0.0676) and HLA-DRB1*14:54:01 (p = 0.0676) alleles were significantly associated with a higher risk of pseudotumour formation, while HLA-DQA1*03:01:01 (p = 0.0240), HLA-DRB1*04:04:01 (p = 0.0453), HLA-C*01:02:01 (p = 0.0453), and HLA-B*27:05:02 (p = 0.0855) were noted to confer risk reduction. Conclusion. These findings confirm the association between specific HLA genotypes and the risk of pseudotumour development around MoM hip resurfacings. Specifically, the two ‘at risk’ alleles (DQB1*05:03:01 and DRB1*14:54:01) may hold clinical value in preoperative screening and prospective surgical decision-making. Cite this article: Bone Jt Open 2023;4(3):182–187

Periprosthetic joint infection is a serious complication of primary total hip replacement (THR) with significant associated morbidity. In acute infection, Debridement, Antibiotics and Implant Retention (DAIR) may be considered. Current national guidelines recommend a DAIR should be performed by “an experienced arthroplasty surgeon┕ but do not specify the need for this to be a revision arthroplasty surgeon. We investigated outcomes in our NHS Trust of DAIR procedures performed by revision and non-revision arthroplasty surgeons. Infection registry data and patient records were analysed for all DAIR procedures of infected primary THRs between 2017 and 2021. Data collected included details of the primary surgery, the presentation with infection, the DAIR procedure and any subsequent complications including return to theatre at any time point. Routinely collected pre- and post-operative patient reported outcome measures (PROMs) were reviewed. 54 periprosthetic joint infections of primary THRs received a DAIR procedure. 41 DAIRs were performed by a revision surgeon and 13 by non-revision surgeons. There was no significant difference in time from primary THR to presentation with infection, time from presentation to DAIR or pre-operative C-reactive protein between the two groups. In 21 (38.9%) patients the DAIR procedure was classed as a treatment failure; 17 patients (31.5%) returned to theatre for further revision surgery, one (2.4%) died related to infection and three (5.6%) had persistent infection but did not receive further surgery. Treatment failure was significantly higher in the non-revision surgeon group (9/13 (69.2%)) than in the revision surgeon group (12/41 (29.3%)) (p = 0.02). Overall, improvement in PROMs after DAIR was seen at both six and 12 months. The overall success rate of DAIR was 61.1% and there was a sustained improvement in PROMs after surgery. However, there was a significant difference in failure rates between revision surgeons and non-revision surgeons

Aims. The aim of this study was to explore the relationship between reason for revision total hip arthroplasty (rTHA) and outcomes in terms of patient-reported outcome measures (PROMs). Methods. We reviewed a prospective cohort of 647 patients undergoing full or partial rTHA at a single high-volume centre with a minimum of two years’ follow-up. The reasons for revision were classified as: infection; aseptic loosening; dislocation; structural failure; and painful THA for other reasons. PROMs (modified Oxford Hip Score (mOHS), EuroQol five-dimension three-level health questionnaire (EQ-5D-3L) score, and visual analogue scales for pain during rest and activity), complication rates, and failure rates were compared among the groups. Results. The indication for revision influenced PROMs improvement over time. This finding mainly reflected preoperative differences between the groups, but diminished between the first and second postoperative years. Preoperatively, patients revised due to infection and aseptic loosening had a lower mOHS than patients with other indications for revision. Pain scores at baseline were highest in patients being revised for dislocation. Infection and aseptic loosening groups showed marked changes over time in both mOHS and EQ-5D-3L. Overall complications and re-revision rates were 35.4% and 9.7% respectively, with no differences between the groups (p = 0.351 and p = 0.470, respectively). Conclusion. Good outcomes were generally obtained regardless of the reason for revision, with patients having the poorest preoperative scores exhibiting the greatest improvement in PROMs. Furthermore, overall complication and reoperation rates were in line with previous reports and did not differ between different indications for rTHA. Cite this article: Bone Joint J 2022;104-B(7):859–866

Aims. In UK there are around 76,000 hip fractures occur each year 10% to 15% of which are undisplaced intracapsular. There is considerable debate whether internal fixation is the most appropriate treatment for undisplaced fractures in older patients. This study describes cannulated hip screws survivorship analysis for patients aged ≥ 60 years with undisplaced intra-capsular fractures. Methods. This was a retrospective cohort study of consecutive patients aged ≥ 60 years who had cannulated screws fixation for Garden I and II fractures in a teaching hospital between March 2013 and March 2016. The primary outcome was further same-side hip surgery. Descriptive statistics were used and Kaplan-Meier estimates calculated for implant survival. Results. A total of 114 operations were performed on 112 patients with a mean age of 80.2 years (SD 8.9). The 30-day and one-year mortality were 1% (n = 1) and 13% (n = 15), respectively. Median follow-up was 6.6 years (interquartile range 6.0 to 7.3). Kaplan-Meier estimates showed a survivorship of 95% at one year and 90% at five years (95% confidence interval 84% to 95%) for cannulated screws. Nine patients underwent further hip surgery: four revision to total hip arthroplasty, one revision to hemiarthroplasty, three removals of screws, and one haematoma washout. Posterior tilt was assessable in 106 patients; subsequent surgery was required in two of the six patients identified with a posterior angle > 20° (p = 0.035 vs angle < 20°). Of the 100 patients with angle < 20°, five-year survivorship was 91%, with seven patients requiring further surgery. Conclusion. This study of cannulated hip screw fixation for undisplaced fractures in patients aged ≥ 60 years reveals a construct survivorship without further operation of 90% at five years. Cannulated screws can be considered a safe reliable treatment option for Garden I and II fractures. Caution should be taken if posterior tilt angle on lateral view exceeds 20°, due to a higher failure rate and reoperation, and considered for similar management to Garden III and IV injuries. Cite this article: Bone Jt Open 2022;3(3):182–188

Aims. Large-diameter metal-on-metal (MoM) total hip arthroplasty (THA) has demonstrated unexpected high failure rates and pseudotumour formation. The purpose of this prospective cohort study is to report ten-year results in order to establish revision rate, prevalence of pseudotumour formation, and relation with whole blood cobalt levels. Methods. All patients were recalled according to the guidelines of the Dutch Orthopaedic Association. They underwent clinical and radiographical assessments (radiograph and CT scan) of the hip prosthesis and whole blood cobalt ion measurements. Overall, 94 patients (95 hips) fulfilled our requirements for a minimum ten-year follow-up. Results. Mean follow-up was 10.9 years (10 to 12), with a cumulative survival rate of 82.4%. Reason for revision was predominantly pseudotumour formation (68%), apart from loosening, pain, infection, and osteolysis. The prevalence of pseudotumour formation around the prostheses was 41%, while our previous report of this cohort (with a mean follow-up of 3.6 years) revealed a 39% prevalence. The ten-year revision-free survival with pseudotumour was 66.7% and without pseudotumour 92.4% (p < 0.05). There was poor discriminatory ability for cobalt for pseudotumour formation. Conclusion. This prospective study reports a minimum ten-year follow-up of large-head MoM THA. Revision rates are high, with the main reason being the sequelae of pseudotumour formation, which were rarely observed after five years of implantation. Blood ion measurements show limited discriminatory capacity in diagnosing pseudotumour formation. Our results evidence that an early comprehensive follow-up strategy is essential for MoM THA to promptly identify and manage early complications and revise on time. After ten years follow-up, we do not recommend continuing routine CT scanning or whole cobalt blood measurements, but instead enrolling these patients in routine follow-up protocols for THA. Cite this article: Bone Jt Open 2022;3(1):61–67

Constrained acetabular inserts provide a solution for both complex primary and revision hip arthroplasty, but there have been ongoing concerns for high risk of failure and their longevity. The Stryker® Trident acetabular insert is pre-assembled with its constrained ring. We believe this to be the largest series of constrained acetabular inserts with a minimum of 5 year follow-up. We retrospectively reviewed all Stryker® Trident ‘All-Poly’ constrained acetabular inserts cemented into bone in our unit between 2008 and 2016. We collated demographic details and reviewed all patients’ radiographs and clinical notes. Indications for surgery, latest Oxford Hip Scores (OHS) and clinical and radiographic complications were identified. 117 consecutive Stryker® Trident ‘All-Poly’ constrained inserts were cemented into bone in 115 patients during the study period with a mean age of 80 (47–97). Most common indications for surgery were recurrent dislocation (47), complex primary arthroplasty (23), revision arthroplasty (19) and failed hemiarthroplasty (12). 41 patients required revision of the acetabular component only. Follow-up was a minimum of 5 years (mean 8.6, range 5–13). There were three 30-day mortalities and six 1-year mortalities. The mean latest OHS was 37 (24–45). Four cups failed in three patients, one at the cement-bone interface, two at the cement-prosthesis interface and one at the bipolar interface. These were treated conservatively in three patient and with excision arthroplasty in one patient. There were four peri-prosthetic fractures, one Vancouver C distal femur fracture treated conservatively and three Vancouver B1 fractures, two treated conservatively and one treated with open reduction internal fixation. There was breakage of one constrained ring with no adverse effects and one superficial wound infection requiring oral antibiotics only. This series demonstrated that despite the elderly and complex nature of these patients’ clinical situations, constrained acetabular inserts offer a useful and pragmatic solution, with relatively low complications, including in our series a cup failure rate of 3% and peri-prosthetic fracture rate of 3%

Total hip arthroplasty (THA) has proved to be an effective treatment modality for sickle-cell hip arthropathy (mosaic-like dense bone due to infarcts). However, mode of failure, survival rates and challenges associated with revision hip arthroplasty in sickle-cell disease patients are mostly unknown. We retrospectively evaluated prospectively collected data from all patients with sickle-cell disease who underwent revision hip arthroplasty from 2016. Patient, surgery, medical and surgical complications related data were collected. The pinnacle and reclaim revision system with gription augments (JJ) was used in all patients. Pre-op and post-op clinical outcome data (both objective and subjective, HOOS Jr and OHS) were recorded. Cumulative success rates were recorded with re-revision surgery as an end point. We performed fifteen revision THAs on 13 patients (mean follow up of 6.6 years). The mean age of the patients was 48 years (range, 30–59). At final follow-up, a statistically significant improvement of mean OHS and HOOS JR scores eas found in all patients. reported (OHS: 34.0 and HOOS JR: 77.7). Cumulative success rate was 100% for re-revision for all reasons at 6 years. Five intensive care unit (ITU) admissions, two vaso-occlusive sickle cell crises, one transfusion-related complication and one acute chest syndrome (ACS) were recorded. On admission, the mean percentage of HbS was 75.25% (64.6–86.4%). Revision arthroplasty in sickle-cell disease patients poses increased risks, with medical and surgical challenges. However, with careful preparation, planning and a multi-disciplinary team approach, revision arthroplasty can result in excellent clinical outcomes and excellent functional scores in the majority of patients in the short and mid-term

We designed a study to evaluate whether (1) there were differences in PROMs between different reasons for revision THA at baseline, (2) there was a different interaction effect for revision THA for all PROMs, and (3) complication and re-revision rates differ between reason for revision THA. Prospective cohort of 647 patients undergoing rTHA, with a minimum of 2 years FU. The reason for revision were classified as infection, aseptic loosening, dislocation, structural failure and painful THA with uncommon causes. PROMs (EQ-5D score, Oxford hip score (OHS), VAS pain, complication and failure rates were compared between different groups. Patients with different reason for revision had improvement of PROMs’ over time. Preoperatively, patients revised due to infection and aseptic loosening had poorer OHS and EQ-5D than patients with other reason for revision. Pain scores at baseline were highest in patients revised due to dislocation. Infection and aseptic loosening groups also showed a significant interaction effect over time in both OHS and EQ-5D. No PROMs significant differences between groups were observed 2 years postoperatively. Overall complications, and re-revision rates were 35.4 and 9.7% respectively. The reason for revision THA did not associate with clinical outcomes. Good outcomes were reached regardless of the reason for revision, as patients with the poorest pre-operative scores had the best improvement in PROMs over time. Complication and re-operation rates were relatively high, in line with previous reports, but did not differ between different reasons for revision THA

Hip instability is one of the most common complications after total hip arthroplasty (THA). Among the possible techniques to treat and prevent hip dislocation, the use of constrained liners is a well-established option. However, there is concern regarding the longevity of these devices due to higher mechanical stress caused by limited hip motion. The primary aim of this paper is to analyze the failure rate of a specific constrained liner in a series of consecutive cases. This study is a retrospective consecutive case series of THA and revision hip arthroplasty (RHA), in which a constrained polyethylene insert was used to treat or prevent hip instability. Patients were divided in 3 different groups (THA for hip fracture, THA for osteoarthrosis, and RHA). Survival analysis was performed for failure, defined as at least one episode of hip dislocation or radiographical signs of acetabular loosening. Logistical regression was used to investigate risk factors for failure. A total of 103 patients were included in the study. Fourteen patients (13,6%) were THA for osteoarthrosis, 60 (58,3%) were THA for hip fracture, and 29(28,2%) were RHA. The median follow-up was 28 months (ranging 12 − 173 months). Failure occurred in 4 cases (3,9%) comprehending 2 dislocations (1,9%) and 2 early acetabular loosening (1,9%). Amongst the groups, there were no cases of failures in the THA due to osteoarthrosis, in the THA for hip fracture there were 3 cases (5%) and in the RHA one case (3,4%). Failure-free survival was not statistically different between groups. There were no risk factors statistically related to failure. The use of constrained acetabular insert to prevent or treat instability achieved an adequate survival time with a low rate of complications. Further studies are necessary to corroborate our findings

Aims. There is a paucity of long-term studies analyzing risk factors for failure after single-stage revision for periprosthetic joint infection (PJI) following total hip arthroplasty (THA). We report the mid- to long-term septic and non-septic failure rate of single-stage revision for PJI after THA. Methods. We retrospectively reviewed 88 cases which met the Musculoskeletal Infection Society (MSIS) criteria for PJI. Mean follow-up was seven years (1 to 14). Septic failure was diagnosed with a Delphi-based consensus definition. Any reoperation for mechanical causes in the absence of evidence of infection was considered as non-septic failure. A competing risk regression model was used to evaluate factors associated with septic and non-septic failures. A Kaplan-Meier estimate was used to analyze mortality. Results. The cumulative incidence of septic failure was 8% (95% confidence interval (CI) 3.5 to 15) at one year, 13.8% (95% CI 7.6 to 22) at two years, and 19.7% (95% CI 12 to 28.6) at five and ten years of follow-up. A femoral bone defect worse than Paprosky IIIA (hazard ratio (HR) 13.58 (95% CI 4.86 to 37.93); p < 0.001) and obesity (BMI ≥ 30 kg/m. 2. ; HR 3.88 (95% CI 1.49 to 10.09); p = 0.005) were significantly associated with septic failure. Instability and periprosthetic fracture were the most common reasons for mechanical failure (5.7% and 4.5%, respectively). The cumulative incidence of aseptic failure was 2% (95% CI 0.4 to 7) at two years, 9% (95% CI 4 to 17) at five years, and 12% (95% CI 5 to 22) at ten years. A previous revision to treat PJI was significantly associated with non-septic failure (HR 9.93 (95% CI 1.77 to 55.46); p = 0.009). At the five-year timepoint, 93% of the patients were alive (95% CI 84% to 96%), which fell to 86% (95% CI 75% to 92%) at ten-year follow-up. Conclusion. Massive femoral bone loss was associated with greater chances of developing a further septic failure. All septic failures occurred within the first five years following the one-stage exchange. Surgeons should be aware of instability and periprosthetic fracture being potential causes of further aseptic revision surgery. Cite this article: Bone Joint J 2021;103-B(7):1247–1253

Residual Legg-Calve-Perthes (LCP) deformities represent one of the most challenging disorders in hip reconstructive surgery. We assessed mid-term PRO. M. s, radiographic correction, complications and survivorship of combined surgical dislocation (SD) and periacetabular osteotomy (PAO) for the treatment of complex LCP deformities. A longitudinal cohort study was performed on 31 hips with complex LCP deformities undergoing combined SD/PAO. Treatment included femoral head reshaping, trochanteric advancement and relative neck lengthening, management of intra-articular lesions and PAO. Twenty-seven (87.1%) had minimum 5-year follow up. Average age was 19.8 years with 56% female and 44% having previous surgery. At a mean 8.4 years, 85% (23/27) of the hips remain preserved (no conversion to THA). The survivorship estimates at 5 and 10 years were 93% and 85%, respectively. The median and interquartile range for mHHS increased from 64 [55–67] to 92 [70–97] (p<0.001), the WOMAC-pain improved from 60 [45–75] to 86 [75–100] (p= 0.001). An additional 19% (n=5) reported symptoms (mHHS <70) at final follow-up. UCLA activity score increased from a median of 8 [6–10] to 9 [7–10] (p=0.207). Structural correction included average improvements of acetabular inclination 15.3. o. ± 7.6, LCEA 20.7° ± 10.8, ACEA 23.4° ± 16.3, and trochanteric height 18 mm ± 10 mm (all, p<0.001). Complications occurred in two (7%) patients including one deep and one superficial wound infection. At intermediate follow-up of combined SD/PAO for complex LCP deformities, 85% of hips are preserved. This procedure provides reliable deformity correction, major pain relief, improved function and acceptable complication/failure rates

Aims. To determine ten-year failure rates following 36 mm metal-on-metal (MoM) Pinnacle total hip arthroplasty (THA), and identify predictors of failure. Patients and Methods. We retrospectively assessed a single-centre cohort of 569 primary 36 mm MoM Pinnacle THAs (all Corail stems) followed up since 2012 according to Medicines and Healthcare Products Regulation Agency recommendations. All-cause failure rates (all-cause revision, and non-revised cross-sectional imaging failures) were calculated, with predictors for failure identified using multivariable Cox regression. Results. Failure occurred in 97 hips (17.0%). The ten-year cumulative failure rate was 27.1% (95% confidence interval (CI) 21.6 to 33.7). Primary implantation from 2006 onwards (hazard ratio (HR) 4.30; 95% CI 1.82 to 10.1; p = 0.001) and bilateral MoM hip arthroplasty (HR 1.59; 95% CI 1.03 to 2.46; p = 0.037) predicted failure. The effect of implantation year on failure varied over time. From four years onwards following surgery, hips implanted since 2006 had significantly higher failure rates (eight years 28.3%; 95% CI 23.1 to 34.5) compared with hips implanted before 2006 (eight years 6.3%; 95% CI 2.4 to 15.8) (HR 15.2; 95% CI 2.11 to 110.4; p = 0.007). Conclusion. We observed that 36 mm MoM Pinnacle THAs have an unacceptably high ten-year failure rate, especially if implanted from 2006 onwards or in bilateral MoM hip patients. Our findings regarding implantation year and failure support recent concerns about the device manufacturing process. We recommend all patients undergoing implantation since 2006 and those with bilateral MoM hips undergo regular investigation, regardless of symptoms. Cite this article: Bone Joint J 2017;99-B:592–600

Proximal femoral replacements are commonly used in oncologic limb salvage procedures. Recently, these megaprostheses have been utilized in complex revision arthroplasties where proximal femoral bone is compromised. The purpose of this study is to evaluate the clinical and radiographic survivorship of proximal femoral replacements as a salvage treatment for bone loss after hip arthroplasty. We retrospectively reviewed the clinical and radiographic outcomes of 31 proximal femoral replacements of a single design between 2004 and 2013 at a single institution. The mean age at time of index surgery was 62 years, 58% were female, and mean BMI was 28.1 Kg/m. 2. The indications and complications associated with megaprosthesis implantation were collected. Average follow-up was 60 months (range 24–120 months). Kaplan-Meier survivorship assessed clinical and radiographic survivorship. Indication for revision, use of a constrained liner and construct length were assessed as risk factors for construct failure. The indications for proximal femoral replacement were periprosthetic infection (n=12, 38.7%), aseptic loosening (n=10, 32.3%), periprosthetic fracture (n=6, 19.3%), and non-union (n=3, 9.7%). A constrained liner was used in 22 hips (71%). The average length of bone resection was 148 cm (range 81–240 cm). There were nine revisions (29.2%): 3 for infection (9.7%) 2 for dislocation (6.5%), 2 for aseptic loosening (6.5%), and 2 for periprosthetic fracture (6.5%). Two of the 3 infections were in patients treated for infection. Overall survivorship was at 70.8%. There was no relation between the length of the bone resection, indication for revision and failure rate. Proximal femoral replacement in non-oncologic revision hip arthroplasty demonstrated a high failure rate at 2–10 year follow-up. Despite the high failure rate, the benefits of this salvage construct are that they allow full weight-bearing and allow rapid mobilization with minimal morbidity

Patients with longstanding hip fusion are predisposed to symptomatic degenerative changes of the lumbar spine, ipsilateral knee and contralateral hip. 1. In such patients, conversion of hip arthrodesis to hip replacement can provide relief of such symptoms. 2 – 4. However, this is a technically demanding procedure associated with higher complication and failure rates than routine total hip replacement. The aim of this study was to determine the functional results and complications in patients undergoing hip fusion conversion to total hip replacement, performed or supervised by a single surgeon. Twenty-eight hip fusions were converted between 1996 and 2016. Mean follow up was 7 years (3 to 18 years). The reasons for arthrodesis were trauma 11, septic arthritis 10, and dysplasia 7. The mean age at conversion was 52.4 years (26 to 77). A trochanteric osteotomy was performed in all hips. Uncemented components were used. A constrained liner was used in 7 hips. Heterotopic ossification prophylaxis was not used in this series. HHS improved a mean of 27 points (37.4 pre-op to 64.3 post-op). A cane was used in 30% of patients before conversion and 80% after. Heterotopic ossification occurred in 12 (42.9%) hips. There was 2 peroneal nerve injuries, 1 dislocation, 1 GT non-union and 1 infection. There have been 5 revisions; 2 for aseptic loosening, 1 for infection, 1 for recurrent dislocation and 1 for leg length discrepancy. Conversion of hip fusion to hip replacement carries an increased risk of heterotopic ossification and neurological injury. We advise prophylaxis against heterotropic ossification. When there is concern about hip stability we suggest that the use of a constrained acetabular liner is considered. Despite the potential for complications, this procedure had a high success rate and was effective in restoring hip function