The advent of modular porous metal augments has ushered in a new form of treatment for acetabular bone loss. The function of an augment can be seen as reducing the size of a defect or reconstituting the anterosuperior/posteroinferior columns and/or allowing supplementary fixation. Depending on the function of the augment, the surgeon can decide on the sequence of introduction of the hemispherical shell, before or after the augment. Augments should always, however, be used with cement to form a unit with the acetabular component. Given their versatility, augments also allow the use of a hemispherical shell in a position that restores the centre of rotation and biomechanics of the hip. Progressive shedding or the appearance of metal debris is a particular finding with augments and, with other radiological signs of failure, should be recognized on serial radiographs. Mid- to long-term outcomes in studies reporting the use of augments with hemispherical shells in revision total hip arthroplasty have shown rates of survival of > 90%. However, a higher risk of failure has been reported when augments have been used for patients with chronic pelvic discontinuity.

Cite this article: Bone Joint J 2024;106-B(4):312–318.

Aims

Total femoral arthroplasty (TFA) is a rare procedure used in cases of significant femoral bone loss, commonly from cancer, infection, and trauma. Low patient numbers have resulted in limited published work on long-term outcomes, and even less regarding TFA undertaken for non-oncological indications. The aim of this study was to evaluate the long-term clinical outcomes of all TFAs in our unit.

Aims. A number of methods have been described to remove a well-fixed humeral implant as part of revision shoulder arthroplasty. These include the use of cortical windows and humeral osteotomies. The router bit extraction technique uses a high-speed router bit to disrupt the bone-implant interface. The implant is then struck in a retrograde fashion with a square-tip impactor and mallet. The purpose of this study was to determine the characteristics and frequency of the different techniques needed for the removal of a well-fixed humeral stem in revision shoulder arthroplasty. Patients and Methods. Between 2010 and 2018, 288 revision shoulder arthroplasty procedures requiring removal of a well-fixed humeral component were carried out at a tertiary referral centre by a single surgeon. The patient demographics, indications for surgery, and method of extraction were collected. Results. Of the 288 revisions, 284 humeral stems (98.6%) were removed using the router bit extraction technique alone. Four humeral stems (1.39%) required an additional cortical window. Humeral osteotomy was not necessary in any procedure. Most of the humeral stems removed (78.8%) were cementless. Of the four humeral stems that required a cortical window, three involved removal of a hemiarthroplasty. Two were cemented and two were cementless. Conclusion. The router bit extraction technique removed a well-fixed humeral component in a very high proportion of patients (98.6%). This method allows surgeons to avoid more invasive approaches involving a cortical window or humeral osteotomy, and their associated complications. Cite this article: Bone Joint J 2019;101-B:1280–1284

Aims. The aim of this study was to identify the effect of the manufacturing characteristics of polyethylene acetabular liners on the survival of cementless and hybrid total hip arthroplasty (THA). Methods. Prospective cohort study using linked National Joint Registry (NJR) and manufacturer data. The primary endpoint was revision for aseptic loosening. Cox proportional hazard regression was the primary analytical approach. Manufacturing variables included resin type, crosslinking radiation dose, terminal sterilization method, terminal sterilization radiation dose, stabilization treatment, total radiation dose, packaging, and face asymmetry. Total radiation dose was further divided into G1 (no radiation), G2 (> 0 Mrad to < 5 Mrad), G3 (≥ 5 Mrad to < 10 Mrad), and G4 (≥ 10 Mrad). Results. A total of 5,329 THAs were revised, 1,290 of which were due to aseptic loosening. Total radiation dose, face asymmetry, and stabilization treatments were found to significantly affect implant survival. G1 had the highest revision risk for any reason and for aseptic loosening and G3 and G4 the lowest. Compared with G1, the adjusted hazard ratio for G2 was 0.74 (95% confidence interval (CI) 0.64 to 0.86), G3 was 0.36 (95% CI 0.30 to 0.43), and G4 was 0.38 (95% CI 0.31 to 0.47). The cumulative incidence of revision for aseptic loosening at 12 years was 0.52 and 0.54 per 100 THAs for G3 and G4, respectively, compared with 1.95 per 100 THAs in G1. Asymmetrical liners had a lower revision risk due to aseptic loosening and reasons other than aseptic loosening compared with symmetric (flat) liners. In G3 and G4, stabilization with vitamin E and heating above melting point performed best. Conclusion. Polyethylene liners with a total radiation dose of ≥ 5 Mrad, an asymmetrical liner face, and stabilization with heating above the melting point demonstrate best survival. Cite this article: Bone Joint J 2020;102-B(1):90–101

Aims

When performing revision total hip arthroplasty using diaphyseal-engaging titanium tapered stems (TTS), the recommended 3 to 4 cm of stem-cortical diaphyseal contact may not be available. In challenging cases such as these with only 2 cm of contact, can sufficient axial stability be achieved and what is the benefit of a prophylactic cable? This study sought to determine, first, whether a prophylactic cable allows for sufficient axial stability when the contact length is 2 cm, and second, if differing TTS taper angles (2° vs 3.5°) impact these results.

Aims. The aim of this study was to use national registry database information to estimate cumulative rates and relative risk of revision due to infection after reverse shoulder arthroplasty. Patients and Methods. We included 17 730 primary shoulder arthroplasties recorded between 2004 and 2013 in The Nordic Arthroplasty Register Association (NARA) data set. With the Kaplan–Meier method, we illustrated the ten-year cumulative rates of revision due to infection and with the Cox regression model, we reported the hazard ratios as a measure of the relative risk of revision due to infection. Results. In all, 188 revisions were reported due to infection during a mean follow-up of three years and nine months. The ten-year cumulative rate of revision due to infection was 1.4% overall, but 3.1% for reverse shoulder arthroplasties and 8.0% for reverse shoulder arthroplasties in men. Reverse shoulder arthroplasties were associated with an increased risk of revision due to infection also when adjusted for sex, age, primary diagnosis, and year of surgery (relative risk 2.41 (95% confidence interval 1.26 to 5.59); p = 0.001). Conclusion. The overall incidence of revision due to infection was low. The increased risk in reverse shoulder arthroplasty must be borne in mind, especially when offering it to men. Cite this article: Bone Joint J 2019;101-B:702–707

Aims. Stemmed tibial components are frequently used in revision total knee arthroplasty (TKA). The purpose of this study was to evaluate patient satisfaction, overall pain, and diaphyseal tibial pain in patients who underwent revision TKA with cemented or uncemented stemmed tibial components. Methods. This is a retrospective cohort study involving 110 patients with revision TKA with cemented versus uncemented stemmed tibial components. Patients who underwent revision TKA with stemmed tibial components over a 15-year period at a single institution with at least two-year follow-up were assessed. Pain was evaluated through postal surveys. There were 63 patients with cemented tibial stems and 47 with uncemented stems. Radiographs and Knee Society Scores were used to evaluate for objective findings associated with pain or patient dissatisfaction. Postal surveys were analyzed using Fisher’s exact test and the independent-samples t-test. Logistic regression was used to adjust for age, sex, and preoperative bone loss. Results. No statistically significant differences in stem length, operative side, or indications for revision were found between the two cohorts. Tibial pain at the end of the stem was present in 25.3% (16/63) of cemented stems and 25.5% (12/47) of uncemented stems (p = 1.000); 74.6% (47/63) of cemented patients and 78.7% (37/47) of uncemented patients were satisfied following revision TKA (p = 0.657). Conclusion. There were no differences in patient satisfaction, overall pain, and diaphyseal tibial pain in cemented and uncemented stemmed tibial components in revision TKA. Patient factors, rather than implant selection and surgical technique, likely play a large role in the presence of postoperative pain. Stemmed tibial components have been shown to be a possible source of pain in revision TKA. There is no difference in patient satisfaction or postoperative pain with cemented or uncemented stemmed tibial components in revision TKA. Cite this article: Bone Joint J 2021;103-B(6 Supple A):165–170

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

Aims. Varus-valgus constrained (VVC) implants are often used during revision total knee arthroplasty (TKA) to gain coronal plane stability. However, the increased mechanical torque applied to the bone-cement interface theoretically increases the risk of aseptic loosening. We assessed mid-term survivorship, complications, and clinical outcomes of a fixed-bearing VVC device in revision TKAs. Methods. A total of 416 consecutive revision TKAs (398 patients) were performed at our institution using a single fixed-bearing VVC TKA from 2007 to 2015. Mean age was 64 years (33 to 88) with 50% male (199). Index revision TKA diagnoses were: instability (n = 122, 29%), aseptic loosening (n = 105, 25%), and prosthetic joint infection (PJI) (n = 97, 23%). All devices were cemented on the epiphyseal surfaces. Femoral stems were used in 97% (n = 402) of cases, tibial stems in 95% (n = 394) of cases; all were cemented. In total, 93% (n = 389) of cases required a stemmed femoral and tibial component. Femoral cones were used in 29%, and tibial cones in 40%. Survivorship was assessed via competing risk analysis; clinical outcomes were determined using Knee Society Scores (KSSs) and range of movement (ROM). Mean follow-up was four years (2 to 10). Results. The five-year cumulative incidence of subsequent revision for aseptic loosening and instability were 2% (95% confidence interval (CI) 0.2 to 3, number at risk = 154) and 4% (95% CI 2 to 6, number at risk = 153), respectively. The five-year cumulative incidence of any subsequent revision was 14% (95% CI 10 to 18, number at risk = 150). Reasons for subsequent revision included PJI (n = 23, of whom 12 had previous PJI), instability (n = 13), and aseptic loosening (n = 11). The use of this implant without stems was found to be a significant risk factor for subsequent revision (hazard ratio (HR) 7.58 (95% CI 3.98 to 16.03); p = 0.007). KSS improved from 46 preoperatively to 81 at latest follow-up (p < 0.001). ROM improved from 96° prerevision to 108° at latest follow-up (p = 0.016). Conclusion. The cumulative incidence of subsequent revision for aseptic loosening and instability was very low at five years with this fixed-bearing VVC implant in revision TKAs. Routine use of cemented and stemmed components with targeted use of metaphyseal cones likely contributed to this low rate of aseptic loosening. Cite this article: Bone Joint J 2020;102-B(4):458–462

Aims. Compared with primary total hip arthroplasty (THA), revision surgery can be challenging. The cement-in-cement femoral revision technique involves removing a femoral component from a well-fixed femoral cement mantle and cementing a new stem into the original mantle. This technique is widely used and when carried out for the correct indications, is fast, relatively inexpensive and carries a reduced short-term risk for the patient compared with the alternative of removing well-fixed cement. We report the outcomes of this procedure when two commonly used femoral stems are used. Patients and Methods. We identified 1179 cement-in-cement stem revisions involving an Exeter or a Lubinus stem reported to the Swedish Hip Arthroplasty Register (SHAR) between January 1999 and December 2015. Kaplan-Meier survival analysis was performed. Results. Survivorship is reported up to six years and was better in the Exeter group (91% standard deviation (. sd). 2.8% versus 85% . sd. 5.0%) (p = 0.02). There was, however, no significant difference in the survival of the stem and risk of re-revision for any reason (p = 0.58) and for aseptic loosening (p = 0.97), between revisions in which the Exeter stem (94% . sd. 2.2%; 98% . sd. 1.6%) was used compared with those in which the Lubinus stem (95% . sd. 3.2%; 98% . sd.  2.2%) was used. The database did not allow identification of whether a further revision was indicated for loosening of the acetabular or femoral component or both. Conclusion. The cement-in-cement technique for revision of the femoral component gave promising results using both designs of stem, six years post-operatively. Cite this article: Bone Joint J 2017;99-B(4 Supple B):27–32

Aims. Patients with a failed reverse shoulder arthroplasty (RSA) have limited salvage options. The aim of this study was to determine the outcome of revision RSA when used as a salvage procedure for a failed primary RSA. Patients and Methods. We reviewed all revision RSAs performed for a failed primary RSA between 2006 and 2012, excluding patients with a follow-up of less than two years. A total of 27 revision RSAs were included in the study. The mean age of the patients at the time of revision was 70 years (58 to 82). Of the 27 patients, 14 (52% were female). The mean follow-up was 4.4 years (2 to 10). Results. Six patients (22%) developed complications requiring further revision surgery, at a mean of 1.7 years (0.1 to 5.3) postoperatively. The indication for further revision was dislocation in two, glenoid loosening in one, fracture of the humeral component in one, disassociation of the glenosphere in one, and infection in one. The five-year survival free of further revision was 85%. Five additional RSAs developed complications that did not need surgery, including dislocation in three and periprosthetic fracture in two. Overall, patients who did not require further revision had excellent pain relief, and significant improvements in elevation and external rotation of the shoulder (p < 0.01). The mean postoperative American Shoulder and Elbow Surgeons (ASES), and simple shoulder test (SST) scores were 66 and 7, respectively. Radiological results were available in 26 patients (96.3%) at a mean of 4.3 years (1.5 to 9.5). At the most recent follow-up, six patients (23%) had glenoid lucency, which were classified as grade III or higher in three (12%). Smokers had a significantly increased risk of glenoid lucency (p < 0.01). Conclusion. Revision RSA, when used to salvage a failed primary RSA, can be a successful procedure. At intermediate follow-up, survival rates are reasonable, but dislocation and glenoid lucency remain a concern, particularly in smokers. Cite this article: Bone Joint J 2018;100-B:1493–98

Aims. Periprosthetic joint infection (PJI) remains a challenging complication following total hip arthroplasty (THA). It is associated with high levels of morbidity, mortality and expense. Guidelines and protocols exist for the management of culture-positive patients. Managing culture-negative patients with a PJI poses a greater challenge to surgeons and the wider multidisciplinary team as clear guidance is lacking. Patients and Methods. We aimed to compare the outcomes of treatment for 50 consecutive culture-negative and 50 consecutive culture-positive patients who underwent two-stage revision THA for chronic infection with a minimum follow-up of five years. Results. There was no significant difference in the outcomes between the two groups of patients, with a similar rate of re-infection of 6%, five years post-operatively. Culture-negative PJIs were associated with older age, smoking, referral from elsewhere and pre-operative antibiotic treatment. The samples in the culture-negative patients were negative before the first stage (aspiration), during the first-stage (implant removal) and second-stage procedures (re-implantation). Conclusion. Adherence to strict protocols for selecting and treating culture-negative patients with a PJI using the same two-stage revision approach that we employ for complex culture-positive PJIs is important in order to achieve control of the infection in this difficult group of patients. Cite this article: Bone Joint J 2018;(1 Supple A)100-B:3–8

Aims. The aim of this study was to identify modifiable risk factors associated with mortality in patients requiring revision total hip arthroplasty (THA) for periprosthetic hip fracture. Methods. The electronic records of consecutive patients undergoing revision THA for periprosthetic hip fracture between December 2011 and October 2018 were reviewed. The data which were collected included age, sex, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, the preoperative serum level of haemoglobin, time to surgery, operating time, blood transfusion, length of hospital stay, and postoperative surgical and medical complications. Univariate and multivariate logistic regression analyses were used to determine independent modifiable factors associated with mortality at 90 days and one year postoperatively. Results. A total of 203 patients were identified. Their mean age was 78 years (44 to 100), and 108 (53%) were female. The median time to surgery was three days (interquartile range (IQR) 2 to 5). The mortality rate at one year was 13.8% (n = 28). The commonest surgical complication was dislocation (n = 22, 10.8%) and the commonest medical complication within 90 days of surgery was hospital-acquired pneumonia (n = 25, 12%). Multivariate analysis showed that the rate of mortality one year postoperatively was five-fold higher in patients who sustained a dislocation (odds ratio (OR) 5.03 (95% confidence interval (CI) 1.60 to 15.83); p = 0.006). The rate of mortality was also four-fold higher in patients who developed hospital-acquired pneumonia within 90 days postoperatively (OR 4.43 (95% CI 1.55 to 12.67); p = 0.005). There was no evidence that the time to surgery was a risk factor for death at one year. Conclusion. Dislocation and hospital-acquired pneumonia following revision THA for a periprosthetic fracture are potentially modifiable risk factors for mortality. This study suggests that surgeons should consider increasing constraint to reduce the risk of dislocation, and the early involvement of a multidisciplinary team to reduce the risk of hospital-acquired pneumonia. We found no evidence that the time to surgery affected mortality, which may allow time for medical optimization, surgical planning, and resource allocation. Cite this article: Bone Joint J 2020;102-B(5):580–585

Aims. Few studies have compared survivorship of total shoulder arthroplasty (TSA) with hemiarthroplasty (HA). This observational study compared survivorship of TSA with HA while controlling for important covariables and accounting for death as a competing risk. Patients and Methods. All patients who underwent shoulder arthroplasty in Ontario, Canada between April 2002 and March 2012 were identified using population-based health administrative data. We used the Fine–Gray sub-distribution hazard model to measure the association of arthroplasty type with time to revision surgery (accounting for death as a competing risk) controlling for age, gender, Charlson Comorbidity Index, income quintile, diagnosis, and surgeon factors. Results. During the study period, 5777 patients underwent shoulder arthroplasty (4079 TSA, 70.6%; 1698 HA, 29.4%), 321 (5.6%) underwent revision, and 1090 (18.9%) died. TSA patients were older (TSA mean age 68.4 years (. sd. 10.2) vs HA mean age 66.5 years (. sd. 12.7); p = 0.001). The proportion of female patients was slightly lower in the TSA group (58.0% vs 58.4%). The adjusted association between surgery type and time to shoulder revision interacted significantly with patient age. Compared with TSA patients, revision was more common in the HA group (adjusted-health ratio (HR) 1.214, 95% confidence interval (CI) 0.96 to 1.53) but this did not reach statistical significance. Conclusion. Although there was a trend towards higher revision risk in patients undergoing HA, we found no statistically significant difference in survivorship between patients undergoing TSA or HA. Cite this article: Bone Joint J 2019;101-B:454–460

Aims. The aim of this study was to compare the rate of perioperative complications following aseptic revision total hip arthroplasty (THA) in patients aged ≥ 80 years with that in those aged < 80 years, and to identify risk factors for the incidence of serious adverse events in those aged ≥ 80 years using a large validated national database. Patients and Methods. Patients who underwent aseptic revision THA were identified in the 2005 to 2015 National Surgical Quality Improvement Program (NSQIP) database and stratified into two age groups: those aged < 80 years and those aged ≥ 80 years. Preoperative and procedural characteristics were compared. Multivariate regression analysis was used to compare the risk of postoperative complications and readmission. Risk factors for the development of a serious adverse event in those aged ≥ 80 years were characterized. Results. The study included 7569 patients aged < 80 years and 1419 were aged ≥ 80 years. Multivariate analysis showed a higher risk of perioperative mortality, pneumonia, urinary tract infection and the requirement for a blood transfusion and an extended length of stay in those aged ≥ 80 years compared with those aged < 80 years. Independent risk factors for the development of a serious adverse event in those aged ≥ 80 years include an American Society of Anesthesiologists score of ≥ 3 and procedures performed under general anaesthesia. Conclusion. Even after controlling for patient and procedural characteristics, aseptic revision THA is associated with greater risks in patients aged ≥ 80 years compared with younger patients. This is important for counselling and highlights the need for medical optimization in these vulnerable patients. Cite this article: Bone Joint J 2018;100-B:143–51

Aims. Revision total knee arthroplasty (rTKA) accounts for approximately 5% to 10% of all TKAs. Although the complexity of these procedures is well recognized, few investigators have evaluated the cost and value-added with the implementation of a dedicated revision arthroplasty service. The aim of the present study is to compare and contrast surgeon productivity in several differing models of activity. Materials and Methods. All patients that underwent primary or revision TKA from January 2016 to June 2018 were included as the primary source of data. All rTKA patients were categorized by the number of components revised (e.g. liner exchange, two or more components). Three models were used to assess the potential surgical productivity of a dedicated rTKA service : 1) work relative value unit (RVU) versus mean surgical time; 2) primary TKA with a single operating theatre (OT) versus rTKA with a single OT; and 3) primary TKA with two OTs versus rTKA with a single OT. Results. In total, 4570 procedures were performed: 4128 primary TKAs, 51 TKA liner exchanges, and 391 full rTKAs. Surgical time was significantly different between the primary TKA, liner exchange, and rTKA cohorts (100.6, 97.1, and 141.7 minutes, respectively; p < 0.001). Primary TKA yielded a mean of 7.1% more RVU/min per procedure than rTKA. Our one-OT model demonstrated that primary TKA (n = 4) had a 1.9% RVU/day advantage over rTKA (n = 3). If two OTs are used for primary TKA (n = 6), the outcome strongly favours primary TKA by an added 34.6% RVUs/day. Conclusion. Our results suggest that a dedicated rTKA service would lead to lower surgeon remuneration based on the current RVU paradigm. Revision arthroplasty specialists may need additional or alternative incentives to promote the development of a dedicated revision service. Through such an approach, healthcare organizations could enhance the quality of care provided, but surgeon productivity measures would need to be adjusted to reflect the burden of these cases. Cite this article: Bone Joint J 2019;101-B:675–681

Aims. The use of a noninvasive growing endoprosthesis in the management of primary bone tumours in children is well established. However, the efficacy of such a prosthesis in those requiring a revision procedure has yet to be established. The aim of this series was to present our results using extendable prostheses for the revision of previous endoprostheses. Patients and Methods. All patients who had a noninvasive growing endoprosthesis inserted at the time of a revision procedure were identified from our database. A total of 21 patients (seven female patients, 14 male) with a mean age of 20.4 years (10 to 41) at the time of revision were included. The indications for revision were mechanical failure, trauma or infection with a residual leg-length discrepancy. The mean follow-up was 70 months (17 to 128). The mean shortening prior to revision was 44 mm (10 to 100). Lengthening was performed in all but one patient with a mean lengthening of 51 mm (5 to 140). Results. The mean residual leg length discrepancy at final follow-up of 15 mm (1 to 35). Two patients developed a deep periprosthetic infection, of whom one required amputation to eradicate the infection; the other required two-stage revision. Implant survival according to Henderson criteria was 86% at two years and 72% at five years. When considering revision for any cause (including revision of the growing prosthesis to a non-growing prosthesis), revision-free implant survival was 75% at two years, but reduced to 55% at five years. Conclusion. Our experience indicates that revision surgery using a noninvasive growing endoprosthesis is a successful option for improving leg length discrepancy and should be considered in patients with significant leg-length discrepancy requiring a revision procedure. Cite this article: Bone Joint J 2018;100-B:370–7

Aims. The purpose of this study is to determine if higher volume hospitals have lower costs in revision hip and knee arthroplasty. Materials and Methods. We questioned the Centres for Medicare and Medicaid Services (CMS) Inpatient Charge Data and identified 789 hospitals performing a total of 29 580 revision arthroplasties in 2014. Centres were dichotomised into high-volume (performing over 50 revision cases per year) and low-volume. Mean total hospital-specific charges and inpatient payments were obtained from the database and stratified based on Diagnosis Related Group (DRG) codes. Patient satisfaction scores were obtained from the multiyear CMS Hospital Compare database. Results. High-volume hospitals comprised 178 (30%) of the total but performed 15 068 (51%) of all revision cases, including 509 of 522 (98%) of the most complex DRG 466 cases. While high-volume hospitals had higher Medicare inpatient payments for DRG 467 ($21 458 versus $20 632, p = 0.038) and DRG 468 ($17 003 versus $16 120, p = 0.011), there was no difference in hospital specific charges between the groups. Higher-volume facilities had a better CMS hospital star rating (3.63 versus 3.35, p < 0.001). When controlling for hospital geographic and demographic factors, high-volume revision hospitals are less likely to be in the upper quartile of inpatient Medicare costs for DRG 467 (odds ratio (OR) 0.593, 95% confidence intervals (CI) 0.374 to 0.941, p = 0.026) and DRG 468 (OR 0.451, 95% CI 0.297 to 0.687, p <  0.001). Conclusion. While a high-volume hospital is less likely to be a high cost outlier, the higher mean Medicare reimbursements at these facilities may be due to increased case complexity. Further study should focus on measures for cost savings in revision total joint arthroplasties. Cite this article: Bone Joint J 2017;99-B:1611–17

Aims. Although good clinical outcomes have been reported for monolithic tapered, fluted, titanium stems (TFTS), early results showed high rates of subsidence. Advances in stem design may mitigate these concerns. This study reports on the use of a current monolithic TFTS for a variety of indications. Methods. A multi-institutional retrospective study of all consecutive total hip arthroplasty (THA) and revision total hip arthroplasty (rTHA) patients who received the monolithic TFTS was conducted. Surgery was performed by eight fellowship-trained arthroplasty surgeons at four institutions. A total of 157 hips in 153 patients at a mean follow-up of 11.6 months (SD7.8) were included. Mean patient age at the time of surgery was 67.4 years (SD 13.3) and mean body mass index (BMI) was 28.9 kg/m. 2. (SD 6.5). Outcomes included intraoperative complications, one-year all-cause re-revisions, and subsidence at postoperative time intervals (two weeks, six weeks, six months, nine months, and one year). Results. There were eight intraoperative complications (4.9%), six of which were intraoperative fractures; none occurred during stem insertion. Six hips (3.7%) underwent re-revision within one year; only one procedure involved removal of the prosthesis due to infection. Mean total subsidence at latest follow-up was 1.64 mm (SD 2.47). Overall, 17 of 144 stems (11.8%) on which measurements could be performed had >5 mm of subsidence, and 3/144 (2.1%) had >10 mm of subsidence within one year. A univariate regression analysis found that additional subsidence after three months was minimal. A multivariate regression analysis found that subsidence was not significantly associated with periprosthetic fracture as an indication for surgery, the presence of an extended trochanteric osteotomy (ETO), Paprosky classification of femoral bone loss, stem length, or type of procedure performed (i.e. full revision vs conversion/primary). Conclusion. Advances in implant design, improved trials, a range of stem lengths and diameters, and high offset options mitigate concerns of early subsidence and dislocation with monolithic TFTS, making them a valuable option for femoral revision. Cite this article: Bone Joint J 2020;102-B(2):191–197

Peri-prosthetic infection is amongst the most common causes of failure following total knee replacement (TKR). In the presence of established infection, thorough joint debridement and removal of all components is necessary following which new components may be implanted. This can be performed in one or two stages; two-stage revision with placement of an interim antibiotic-loaded spacer is regarded by many to be the standard procedure for eradication of peri-prosthetic joint infection. . We present our experience of a consecutive series of 50 single-stage revision TKRs for established deep infection performed between 1979 and 2010. There were 33 women and 17 men with a mean age at revision of 66.8 years (42 to 84) and a mean follow-up of 10.5 years (2 to 24). The mean time between the primary TKR and the revision procedure was 2.05 years (1 to 8). Only one patient required a further revision for recurrent infection, representing a success rate of 98%. Nine patients required further revision for aseptic loosening, according to microbiological testing of biopsies taken at the subsequent surgery. Three other patients developed a further septic episode but none required another revision. These results suggest that a single-stage revision can produce comparable results to a two-stage revision. Single-stage revision offers a reduction in costs as well as less morbidity and inconvenience for patients. Cite this article: Bone Joint J 2014;96-B:759–64