Different techniques have been described to address massive bone loss of the acetabulum in revision hip surgery. aMace has gained popularity as it provides customization aiming to restore hip centre and provide good initial stability in cases of large non-contained defects. It takes into account quality of host bone. Its porous defect filling scaffold provides an excellent surface for osteointegration.

Our aim was to assess the short and mid-term outcomes of patients who underwent revision surgery using aMace system.

Ethical approval was obtained. A retrospective study included all patients who had aMace between June 2013 and October 2022 allowing for a minimum of 12-months follow-up. Patients’ demographics, indication, bone-loss severity, reconstruction details, re-operation, complications, mortality, pain and function were assessed.

52 cases were performed by 13 surgeons with median 51 months follow-up. Median age was 72.7 years. 86.5% were female. Average BMI was 25.3. Average ASA grade was 3.

65% were classified as Paprosky IIIB and 32% were IIIA.

73% were found to have poor bone quality on CT. Main indication for aMace was massive bone loss/discontinuity secondary to aseptic loosening in 88.5%.

77% underwent single-stage revision. 53.8% had 2 or more previous revisions. 71% underwent stem revision in the same setting. 77% received a dual mobility bearing.

Re-operation rate was 5.7% for instability and femoral PPF. LLD was reported in 9.6%.

Permanent Sciatic nerve palsy occurred in 3.8% of the cases.

30-days mortality was 1.9%.

Statistically significant post-op improvements in pain and mobility were reported (p<0.001). None of the acetabular components have been revised.

Our study shows satisfactory surgical outcomes with a relatively low complication rate and significant pain and mobility improvements in the early to mid-term stages.

We recommend these costly cases to be done in highly specialist centres adopting MDT approach.

Between April 1992 and November 1998 we used 34 massive proximal femoral allografts for femoral reconstruction at revision hip arthroplasty. Seven patients have died and two have been lost to follow-up. There were thus 25 grafts in 24 patients for review. The mean follow-up was 53 months (16 to 101). By the time of the review two patients had undergone a further revision for failure of the allograft. Another had required secondary plating and grafting at the graft-host junction for symptomatic nonunion. One had recurrence of deep sepsis and was being managed conservatively.

Trochanteric union was considered to have occurred radiologically in 16 of the 25 grafts and union at the host-graft junction in 20. Resorption of the allograft was significant in only two hips. We recommend this technique in cases in which femoral bone loss has been catastrophic.

Aims. The burden of revision total hip arthroplasty (rTHA) continues to grow. The surgery is complex and associated with significant costs. Regional rTHA networks have been proposed to improve outcomes and to reduce re-revisions, and therefore costs. The aim of this study was to accurately quantify the cost and reimbursement for a rTHA service, and to assess the financial impact of case complexity at a tertiary referral centre within the NHS. Methods. A retrospective analysis of all revision hip procedures was performed at this centre over two consecutive financial years (2018 to 2020). Cases were classified according to the Revision Hip Complexity Classification (RHCC) and whether they were infected or non-infected. Patients with an American Society of Anesthesiologists (ASA) grade ≥ III or BMI ≥ 40 kg/m. 2. are considered “high risk” by the RHCC. Costs were calculated using the Patient Level Information and Costing System (PLICS), and remuneration based on Healthcare Resource Groups (HRG) data. The primary outcome was the financial difference between tariff and cost per patient episode. Results. In all, 199 revision episodes were identified in 168 patients: 25 (13%) least complex revisions (H1); 110 (55%) complex revisions (H2); and 64 (32%) most complex revisions (H3). Of the 199, 76 cases (38%) were due to infection, and 78 patients (39%) were “high risk”. Median length of stay increased significantly with case complexity from four days to six to eight days (p = 0.006) and for revisions performed for infection (9 days vs 5 days; p < 0.001). Cost per episode increased significantly between complexity groups (p < 0.001) and for infected revisions (p < 0.001). All groups demonstrated a mean deficit but this significantly increased with revision complexity (£97, £1,050, and £2,887 per case; p = 0.006) and for infected failure (£2,629 vs £635; p = 0.032). The total deficit to the NHS Trust over two years was £512,202. Conclusion. Current NHS reimbursement for rTHA is inadequate and should be more closely aligned to complexity. An increase in the most complex rTHAs at major revision centres will likely place a greater financial burden on these units. Cite this article: Bone Jt Open 2023;4(8):559–566

Revision total hip arthroplasty (rTHA) can be complex and associated with significant cost, with an increasing burden within the UK and globally. Regional rTHA networks have been proposed aiming to improve outcomes, reduce re-revisions and therefore costs. The aim of this study was to accurately quantify the cost and reimbursement for the rTHA service and to assess the financial impact of case complexity at a tertiary referral centre within the NHS. A retrospective analysis of all revision hip procedures was performed over two consecutive financial years (2018–2020). Cases were classified according to the Revision Hip Complexity Classification (RHCC) and by mode of failure; infected or non-infected. Patients of ASA grade of 3 or greater or BMI over 40 are considered “high-risk” by the RHCC. Costs were calculated using PLICS and remuneration based on the HRG data. The primary outcome was the financial difference between tariff and cost per episode per patient. Comparisons between groups were analysed using analysis of variance and two-tailed unpaired t-test. 199 revision episodes were identified in 168 patients: 25 (13%) least complex revisions (H1), 110 (55%) complex revisions (H2) and 64 (32%) most complex revisions (H3). 76 (38%) cases were due to infection. 78 (39%) of patients were in the “high-risk” group. Median length of stay increased with case complexity from 4, to 6 to 8 days (p=0.17) and significantly for revisions performed for infection (9 vs 5 days; p=0.01). Cost per episode increased significantly between complexity groups (p=0.0002) and for infected revisions (p=0.003). All groups demonstrated a mean deficit, but this significantly increased with revision complexity (£301, £1,820 and £4,757 per case; p=0.02) and for infected failure (£4,023 vs £1,679; p=0.02). The total deficit to the trust for the two-years was £512,202. Current NHS reimbursement for rTHA is inadequate and should be more closely aligned to complexity. An increase in the most complex rTHA at major revision centres (MRC) will likely place a greater financial burden on these units

Aims. Dislocation remains a leading cause of failure following revision total hip arthroplasty (THA). While dual-mobility (DM) bearings have been shown to mitigate this risk, options are limited when retaining or implanting an uncemented shell without modular DM options. In these circumstances, a monoblock DM cup, designed for cementing, can be cemented into an uncemented acetabular shell. The goal of this study was to describe the implant survival, complications, and radiological outcomes of this construct. Methods. We identified 64 patients (65 hips) who had a single-design cemented DM cup cemented into an uncemented acetabular shell during revision THA between 2018 and 2020 at our institution. Cups were cemented into either uncemented cups designed for liner cementing (n = 48; 74%) or retained (n = 17; 26%) acetabular components. Median outer head diameter was 42 mm. Mean age was 69 years (SD 11), mean BMI was 32 kg/m. 2. (SD 8), and 52% (n = 34) were female. Survival was assessed using Kaplan-Meier methods. Mean follow-up was two years (SD 0.97). Results. There were nine cemented DM cup revisions: three for periprosthetic joint infection, three for acetabular aseptic loosening from bone, two for dislocation, and one for a broken cup-cage construct. The two-year survivals free of aseptic DM revision and dislocation were both 92%. There were five postoperative dislocations, all in patients with prior dislocation or abductor deficiency. On radiological review, the DM cup remained well-fixed at the cemented interface in all but one case. Conclusion. While dislocation was not eliminated in this series of complex revision THAs, this technique allowed for maximization of femoral head diameter and optimization of effective acetabular component position during cementing. Of note, there was only one failure at the cemented interface. Cite this article: Bone Joint J 2024;106-B(4):352–358

The Revision Hip Complexity Classification (RHCC) was developed by modified Delphi system in 2022 to provide a comprehensive, reproducible framework for the multidisciplinary discussion of complex revision hip surgery. The aim of this study was to assess the validity, intra-relater and inter-relater reliability of the RHCC. Radiographs and clinical vignettes of 20 consecutive patients who had undergone revision of Total Hip Arthroplasty (THA) at our unit during the previous 12-month period were provided to observers. Five observers, comprising 3 revision hip consultants, 1 hip fellow and 1 ST3-8 registrar were familiarised with the RHCC. Each revision THA case was classified on two separate occasions by each observer, with a mean time between assessments of 42.6 days (24–57). Inter-observer reliability was assessed using the Fleiss™ Kappa statistic and percentage agreement. Intra-observer reliability was assessed using the Cohen Kappa statistic. Validity was assessed using percentage agreement and Cohen Kappa comparing observers to the RHCC web-based application result. All observers were blinded to patient notes, operation notes and post-operative radiographs throughout the process. Inter-observer reliability showed fair agreement in both rounds 1 and 2 of the survey (0.296 and 0.353 respectively), with a percentage agreement of 69% and 75%. Inter-observer reliability was highest in H3-type revisions with kappa values of 0.577 and 0.441. Mean intra-observer reliability showed moderate agreement with a kappa value of 0.446 (0.369 to 0.773). Validity percentage agreement was 44% and 39% respectively, with mean kappa values of 0.125 and 0.046 representing only slight agreement. This study demonstrates that classification using the RHCC without utilisation of the web-based application is unsatisfactory, showing low validity and reliability. Reliability was higher for more complex H3-type cases. The use of the RHCC web app is recommended to ensure the accurate and reliable classification of revision THA cases

Periprosthetic femoral fractures are increasingly seen in recent years, adding considerable burden to the National Health Service. These require complex revision or fixation and prolonged post-operative care, with significant morbidity with associated costs. The purpose of this study was to assess whether the size of femoral cement mantle is associated with periprosthetic femoral fractures (PPF). This retrospective study was carried out on a cohort of 49 patients (Fracture Group - FG) who previously had a revision procedure following a proximal PPF between 2010 and 2021. Inclusion criteria – all primary cemented total hip replacements (THR). Exclusion criteria – complex primary THR, any implant malposition that required early revision surgery or any pre-fracture stem loosening. The antero-posterior (AP) radiographs from this cohort of patients were assessed and compared to an age, sex, time since THR-matched control group of 49 patients without PPF (Control Group - CG). Distal cement mantle area (DCMA) was calculated on an AP radiograph of hip; the position of the femoral stem tip prior to fracture was also recorded: valgus, varus or central. Limitations: AP radiographs only. Statistical analyses were performed using Microsoft® Excel. Chi-square test demonstrated statistically significant difference in DCMA between FG and CG. DCMA of 700 to 900 mm² appeared to be protective when compared to DCMA of 0 to 300 mm². Also, a valgus position observed in 23% in FG Vs 4 % in CG increased the risk, with a smaller area of DCMA. This study demonstrates and recommends that a size of 700 – 900 mm² of the DCMA is protective against periprosthetic fractures, which are further influenced by the positioning of the distal stem tip. This could be due to the gradual decrease in the stiffness gradient from proximal to distal around the stem tip than steep changes, thereby decreasing possibility of a stress riser just distal to the cement mantle or restrictor. Further biomechanical research specific to this finding may be helpful to validate the observation, progressing to suggest a safe standardised surgical technique

The management of severe acetabular bone defects poses a complex challenge in revision hip arthroplasty. Although biological fixation materials are currently dominant, cage has played an important role in complex acetabular revision in the past decades, especially when a biological prosthesis is not available. The purpose of this study is to report the long-term clinical and radiographic results of Paprosky type Ⅲ acetabular bone defects revised with cage and morselized allografts. We retrospectively analyzed 45 patients who underwent revision hip arthroplasty with cage and morselized allografts between January 2007 and January 2019. Forty-three patients were followed up. There were 19 Paprosky type IIIA bone defect patients and 24 Paprosky type IIIB bone defect patients and 7 patients of the 24 were also with pelvic discontinuity. Clinical assessment included Harris Hip Score (HHS) and Short Form-12 (SF-12). Radiographic assessment included cage stability, allografts incorporation, and center of rotation. All patients were followed up with a mean follow-up of 10.6 years, HHS and SF-12 improved significantly at last follow-up in comparison to the preoperative. There were 2 re-revisions, one at 5 years after surgery, another at 13.6 years after surgery. Two patients had nonprogressive radiolucency in zone III and the junction of zone II and zone III at the bone implant interface. Allografts of 40 (93%) cases incorporated fully. The combination of cage and morselized allograft is an alternative option for acetabular revision with Paprosky type III bone defects with satisfactory long-term follow-up results

Chondral hip injuries are common secondary to femoroacetabular impingement (FAI). Treatment with arthroscopic procedures including chondroplasty and microfracture is becoming increasingly common but literature is limited to case series at specialist centres. The aim of this study is to compare outcomes of arthroscopic acetabular chondral procedures using the NAHR dataset (UK) which represents the largest series to date. All adult Arthroscopies recorded in the NAHR from Jan 2012 were available for inclusion. Exclusions included significant arthritis and femoral, complex or revision chondral procedures. Patients completed iHOT-12 & EQ-5D Index pre-operatively, 6 and 12 months. Data was analysed using T-test/ANOVA for between group/within group for continuous variables, chi square test for categorical variables and linear regression model for multivariable analysis. 5,752 patients, 60% female. 27% Chondroplasty, 5% Microfracture, 68% no Chondral Procedure. Maximum acetabular Outerbridge classification 14% Grade 1, 15% Grade 2, 17% Grade 3, 8% Grade 4, 9% no damage, not recorded in 37%. Higher proportion of Cam impingement in association with chondral treatments and a larger proportion of patients with no impingement recorded in group with no chondral procedures. There was a significant improvement versus baseline for all groups in iHOT-12 and EQ-5D Index (p<0.0001) including Grade four Outerbridge. There was significantly greater improvement in pre-operative scores in the chondroplasty group compared to the microfracture group at 6 and 12 months (p<0.05). Following hip arthroscopy, patients with chondral procedures experienced improved outcome scores despite Outerbridge 4 chondral damage. Presence of cam lesions are more commonly associated with chondral treatments. Good outcomes were maintained up to 12 months for chondral procedures, regardless of age or impingement pathology however pincers improved less and patients over 40 years took longer to see improvement

Introduction. Custom flanged acetabular components (CFAC) have been shown to be effective in treating complex acetabular reconstructions in revision total hip arthroplasty (THA). However, the specific patient factors and CFAC design characteristics that affect the overall survivorship remain unclear. Once the surgeon opts to follow this treatment pathway, numerous decisions need to be made during the pre-operative design phase and during implantation, which may influence the ultimate success of CFAC. The goal of this study was to retrospectively review the entire cohort of CFAC cases performed at a large volume institution and to identify any patient, surgeon, or design factors that may be related to the long-term survival of these prostheses. Methods. We reviewed 96 CFAC cases performed in 91 patients between 2004 and 2017, from which 36 variables were collected spanning patient demographics, pre-operative clinical and radiographic features, intraoperative information, and implant design characteristics. Patient demographics and relevant clinical features were collected from individual medical records. Radiographic review included analysis of pre-operative radiographs, computer tomographic (CT) scans, and serial post-operative radiographs. Radiographic failure was defined as loosening or gross migration as determined by a board-certified orthopedic surgeon. CFAC implant design characteristics and intra-operative features were collected from the design record, surgical record and post-operative radiograph for each case respectively. Two sets of statistical analyses were performed with this dataset. First, univariate analyses were performed for each variable, comprising of a Pearson chi-square test for categorical variables and an independent t-test for continuous variables. Second, a random forest supervised machine learning method was applied to identify the most influential variables within the dataset, which were then used to perform a bivariable logistic regression to generate odds ratios. Statistical significance for this study was set at p < 0.05. Results. Radiographic failures occurred in 22/96 (23%) of cases with 12/96 (13%) undergoing re-revision (time to revision: Mean 25.1 months; Range: 3 – 84, SD 26.5). No relationship between radiographic failure and the preoperative Paprosky grade or the presence of a discontinuity was observed. The rate of radiographic failure (loosening and/or migration) was inversely associated with age, with increased failure seen in patients who were younger at the time of surgery; (mean age: 54.4±13.0 v. 64.8±11.4 years; p=0.007). Patients whose initial diagnosis was not osteoarthritis were more likely to fail than those with primary OA (OR: 3.79, p=0.0173) and were younger at the time of surgery (p=0.013). The presence of ischial screws from previous surgery (28%) was also an independent risk factor for failure (OR: 3.11, p=0.021). Random forest analysis identified the age at index procedure and the location of the inferior-most ischial screw as the most sensitive predictors of radiographic failure. As patient age at the time of surgery increased, there was subsequent a decreased rate of failure (OR: 0.93 odds ratio per year, p =0.005). When the bottom-most ischial screw was within the top half of the obturator foramen, it was 4 times more likely to fail than when this screw was located at the bottom half of the obturator foramen (OR = 3.98, p=0.046) (p < 0.05). Discussion and Conclusion. This study was able to identify the patient and design variables predictive of survival of CFAC prostheses used in complex revision THA. Younger patients (<55years) are at increased risk for failure either due to a more active lifestyle or because they have a non-OA primary diagnosis that predisposes them to earlier THA. Compromised ischial bone stock or inadequate ischial fixation both had a significant impact on CFAC implant survivorship as both the presence of pre-CFAC ischial screw fixation and lack of inferior ischial fixation correlated with increased rate of failure. These findings highlight the importance of rigid ischial fixation sufficient to resist the high pull-out forces generated during activities of daily living

Aims

With increasing burden of revision hip arthroplasty (THA), one of the major challenges is the management of proximal femoral bone loss associated with previous multiple surgeries. Proximal femoral arthroplasty (PFA) has already been popularized for tumour surgeries. Our aim was to describe the outcome of using PFA in these demanding non-neoplastic cases.

Aims

The aim of this study is to report the long-term outcomes of instrumented femoral revisions with impaction allograft bone grafting (IBG) using the X-change femoral revision system at 30 years after introduction of the technique.

Aims

The aim of this modified Delphi process was to create a structured Revision Hip Complexity Classification (RHCC) which can be used as a tool to help direct multidisciplinary team (MDT) discussions of complex cases in local or regional revision networks.

Highly porous tantalum cups have been used in complex acetabular revisions for nearly 20 years but reports of long term results are limited. This study was designed to report ten year results of revision using a single porous tantalum cup design with special attention to re-operation for any reason, all-cause revision, and revision for aseptic loosening. Retrospective review of all revision THA cases performed from 1999–2006 using a highly porous tantalum acetabular component design with multiple screw holes and a cemented polyethylene liner (Zimmer Biomet, Warsaw, IN). Our institutional medical record and total joint registry were used to assess follow-up and xrays were reviewed. The Paprosky classification system was used to rate acetabular bone loss. Radiographic loosening was defined as new/progressive radiolucencies in all 3 acetabular zones, or cup migration (>2mm). Kaplan-Meier survivorship was used to assess survivorship free of cup revision/removal for any reason, and free of revision for aseptic loosening. Between 1999 and 2006 this tantalum cup was used in 916 revisions. Mean age: 66 (±6), BMI: 29 (±6), and male: 42%. Indications for revision: aseptic loosening 346 (38%), osteolysis 240 (26%), and infected arthroplasty 168 (18%). Large (3A or 3B) bone defects were present in 260, and pelvic discontinuity in 61. Reoperation for any reason: 133 (15%), but 84 of 133 cases did not require cup revision for instability (38) or femoral failure (24). Tantalum cup removal/revision was required in 49 (5.3%) for deep infection (39) and recurrent dislocation (6), and aseptic loosening (4). 10 year survivorship free of cup revision for any reason: 95% and for aseptic loosening: 99%. Radiographic review (mean 10 years): suspicious for aseptic loosening in another 4 cups. A highly porous tantalum acetabular component with multiple screws and a cemented polyethylene insert provided durable long term fixation for an array of acetabular revision problems. Long term aseptic loosening was very rare (<1%) and cup removal was mainly related to deep infection, and rarely dislocation

Aims

We aimed to compare the implant survival, complications, readmissions, and mortality of Vancouver B2 periprosthetic femoral fractures (PFFs) treated with internal fixation with that of B1 PFFs treated with internal fixation and B2 fractures treated with revision arthroplasty.

Introduction. Surgical simulation and ‘virtual’ surgical tools are becoming recognised as essential aids for speciality training in Trauma & Orthopaedics, as evidenced by the BOA T&O Simulation Curriculum 2013. 1,2. The current generation of hip arthroplasty simulators, including cadaveric workshops, offers the trainee limited exposure to reproducible real life bony pathology. We developed and implemented a novel training course using pathological dry bone models generated from real patient cases to support senior orthopaedic trainees and new consultants in developing knowledge and hands on skills in complex total hip arthroplasty. Patient/Materials & Methods. A two-day programme for 20 delegates was held at a specialist centre for hip arthroplasty. Three complex femoral and three complex acetabular cases were identified from patients seen at our centre. 3D models were printed from CT scans and dry bone models produced (using a mold-casting process), enabling each delegate to have a copy of each case at a cost of around £30 per case per delegate (Figure 1). The faculty was led by 4 senior Consultant revision hip surgeons. A computerised digitising arm was used to measure cup positioning and femoral stem version giving candidates immediate objective feedback (Figure 2). Candidate experience and satisfaction with the course and models was evaluated with a standardised post-course questionnaire. Results. 91% of respondents rated overall course satisfaction good or very good with 100% stating learning objectives were met or exceeded. 100% of delegates rated the bone model workshop cases as good or very good for the acetabular course, and 88% for the femoral course. Discussion. This course has been shown to enhance learning of surgical techniques and skills in complex hip surgery. Conclusion. We have developed a novel, effective and low cost training simulation method using pathological dry bone models for complex and revision hip arthroplasty which could be developed for other anatomical areas

Aims

The aim of this study was to develop a novel computational model for estimating head/stem taper mechanics during different simulated assembly conditions.

Aims

Hip resurfacing arthroplasty (HRA) is typically indicated for young and active patients. Due to the longevity of arthroplasty, these patients are likely to undergo revision surgery during their lifetime. There is a paucity of information on the long-term outcome of revision surgeries performed after failed HRA. The aim of our study was to provide survivorship data as well as clinical scores after HRA revisions.

Aims

The increasing infection burden after total hip arthroplasty (THA) has seen a rise in the use of two-stage exchange arthroplasty and the use of increasingly powerful antibiotics at the time of this procedure. As a result, there has been an increase in the number of failed two-stage revisions during the past decade. The aim of this study was to clarify the outcome of repeat two-stage revision THA following a failed two-stage exchange due to recurrent prosthetic joint infection (PJI).

Aims

The aim of this retrospective audit was to determine the route of referral or presentation of patients requiring revision following primary total hip arthroplasty (THA).