All-cause Revision Research Articles

The Impact of Changing Total Knee Arthroplasty Implants at a High-Volume Institution

BackgroundThe ability of a group of high-volume arthroplasty surgeons to simultaneously change their preferred primary total knee arthroplasty (TKA) implant of choice to another, has not been explored in the literature to date. The main hypothesis was that such a change could be made with no significant impact on clinical outcomes. MethodsThis is a retrospective cohort study comparing the last 500 consecutive TKAs implanted of a routinely used TKA implant (NexGen; Zimmer, Warsaw, IN) with the first 500 consecutive TKAs implanted of a newly adopted TKA implant (Triathlon; Stryker, Mahwah, NJ) at an institutional level. Primary outcomes of importance included all complications that occurred either intraoperatively or early postoperatively, early all-cause revision rate, and early reintervention rate. ResultsThere was a 1.2% (n = 6) complication rate in the NexGen cohort compared to 0.8% (n = 4) in the newly adopted Triathlon cohort (P = .75). The rate of intraoperative fracture was 1% in the NexGen cohort and 0.6% in the Triathlon cohort (P = .72). The early all-cause revision rate for the NexGen TKA was 1% (n = 5) compared to 0.8% (n = 4) in the Triathlon cohort (P = 1.0). The manipulation under anesthesia (MUA) rate in the NexGen cohort was 2.4% compared to 4.6% in the Triathlon cohort (P = .058). The only predictor variable associated with MUA rate was American Society of Anesthesiologists grade, where there was a significantly lower rate of MUA with a higher American Society of Anesthesiologists grade (P = .042). ConclusionIt is possible to implement the institution-wide adoption of an established, high-performing TKA implant without any negative implications in relation to early revision rates, perioperative complication rates, and reintervention rates. This study is the first of its kind to be reported in the literature.

Dual-mobility constructs versus large femoral head bearings in primary and revision total hip arthroplasty: a systematic review and meta-analysis of comparative studies.

Both dual-mobility (DM) constructs and large femoral head bearings (⩾36 mm) reduce dislocation following total hip arthroplasty (THA). There is limited research comparing DM with large bearings. A systematic review of published literature was performed including studies that compared DM with large femoral head bearings in primary or revision THA according to PRISMA guidelines. The primary outcome was revision surgery for dislocation. The secondary outcome was all-cause revision surgery. Other complications were recorded. 2 authors independently selected studies, performed data extraction, and risk of bias assessment. Treatment effects were assessed using odds ratios and data were pooled using a fixed-effect model, where appropriate. 9 studies, all retrospective, met the final inclusion criteria. 2722 patients received DM and 9,789 large femoral head bearings. The difference in the odds of revision surgery for dislocation (OR 0.67; 95% CI, 0.45-1.01; p = 0.06) and aseptic loosening are unclear (OR 0.61; 95% CI, 0.36-1.05; p = 0.07); including important benefits and no difference. There was a benefit favouring DM for the risk of all-cause revision (OR 0.70; 95% CI, 0.56-0.86; p = 0.001), revision for fracture (OR 0.49; 95% CI, 0.29-0.81; p = 0.005) and dislocation not requiring revision (OR 0.29; 95% CI, 0.14-0.57; p < 0.001). The estimate in the difference in the odds of revision surgery for infection was imprecise (OR 0.78; 95% CI, 05.1-1.20; p = 0.26). This study provides evidence that there may be clinically relevant benefits of DM constructs over large femoral head bearings. Prospective randomised studies are warranted given these findings.

The 45-year evolution of the Mathys RM monoblock cups: have the paradigm shifts been worthwhile?

The Robert Mathys (RM) monoblock uncemented cup is a design less commonly used in primary total hip replacement. It's purported advantages over modular cemented cups are: (1) its modulus of elasticity approximating bone, thus mimicking load transmission and the biomechanical behaviour of the cup to better match stresses on the acetabulum, leading to bone-preservation; and (2) as a 1-piece cup there is absence of a mobile interface between a liner and shell, preventing backside wear. Since its inception in 1983 there have been 3 major design changes: the RM Classic, the RM Pressfit, and the RM Vitamys with the most modern polyethylene (vitamin E). In a retrospective cohort study of the New Zealand Joint Registry, all designs of RM acetabular cup were reviewed. Data were included from1998 to 2018. All-cause revision rates, reasons for revision and the Oxford Hip Score (OHS) were assessed. In total 13,272 acetabular cups were included. The all-cause revision rates did not differ between the designs. Revision rates for aseptic loosening in the RM Vitamys were lower, but the follow-up was shorter and more larger heads were used. There was no difference in the OHS. All implant designs were safe. The use of larger heads led to a decrease in revisions due to dislocation. It has to be waited out whether the RM Vitamys performs superior in the long-term due to the highly cross-linked polyethylene.

Association of perioperative thromboprophylaxis on revision rate due to infection and aseptic loosening in primary total hip arthroplasty - new evidence from the Nordic Arthroplasty Registry Association (NARA).

Background and purposeResults regarding the impact of anticoagulants on revision rate are conflicting. We examined the association between the use of low molecular weight heparin (LMWH) or non-vitamin K oral anticoagulants (NOACs) as thromboprophylaxis after primary total hip arthroplasty (THA) and the revision rate due to infection, aseptic loosening, and all causes.Patients and methodsWe conducted a cohort study (n = 53,605) based on prospectively collected data from the national hip arthroplasty registries from Denmark and Norway. The outcome was time to revision due to infection, aseptic loosening, and all causes, studied separately. Kaplan– Meier (KM) survival analysis and a Cox proportional hazard model was used to estimate implant survival and cause-specific hazard ratios (HRs) with 95% confidence intervals (CI) adjusting for age, sex, Charlson Comorbidity Index, fixation type, start, and duration of thromboprophylaxis, and preoperative use of Vitamin K antagonists, NOAC, aspirin, and platelet inhibitors as confounders.ResultsWe included 40,451 patients in the LMWH group and 13,154 patients in the NOAC group. Regarding revision due to infection, the 1-year and 5-year KM survival was 99% in both the LMWH group and in the NOAC group. During the entire follow-up period, the adjusted HR for revision due to infection was 0.9 (CI 0.7–1.1), 1.6 (CI 1.3–2.1) for aseptic loosening, and 1.2 (CI 1.1–1.4) for all-cause revision for the NOAC compared with the LMWH group. The absolute differences in revision rates between the groups varied from 0.2% to 1%.InterpretationCompared with LMWH, NOACs were associated with a slightly lower revision rate due to infection, but higher revisions rates due to aseptic loosening and all-cause revision. The absolute differences between groups are small and most likely not clinically relevant. In addition, the observed associations might partly be explained by selection bias and unmeasured confounding, and should be a topic for further research.

Outcomes following Total Hip Arthroplasty for Femoral Head Osteonecrosis in Patients with History of Solid Organ Transplant.

Osteonecrosis of the femoral head (ONFH) is a potentially debilitating condition, often requiring total hip arthroplasty (THA). Patients with solid organ transplant (SOT) are at increased risk of postoperative complications after THA for osteoarthritis. The objective of the present study is to evaluate SOT as a potential risk factor for complication after THA for ONFH. This is a retrospective study that identified patients with SOT who underwent THA for ONFH from 2005 to 2014 in a national insurance database and compared them to 5:1 matched controls without transplant. Subgroup analyses of patients with renal transplant (RT) and those with non-RT were also analyzed. A logistic regression analysis was used to compare rates of mortality, hospital readmission, emergency room (ER) visits, infection, revision, and dislocation while controlling for confounders. Differences in hospital charges, reimbursement, and length of stay (LOS) were also compared. 996 patients with SOT who underwent THA were identified and compared to 4,980 controls. SOT patients experienced no increased risk of early postoperative complications compared to controls. Solid organ transplant was associated with higher resource utilization and LOS. Renal transplant patients were found to have significantly higher risk of hospital readmission at 30 days (odds ratio [OR] 1.77; p = 0.001) and 90 days (OR 1.62; p < 0.001) and hospital LOS (p < 0.001), but had lower risk of infection (OR 0.65; p = 0.030). Non-RT patients had higher rate of ER visits at 30 days (OR 2.26; p = 0.004) but lower rates of all-cause revision (OR 0.22; p = 0.043). Patients with history of SOT undergoing THA for ONFH utilize more hospital resources with longer LOS and greater risk of readmission but are not necessarily at an increased risk of early postoperative complications.

Preoperative Weight Loss and Postoperative Weight Gain Independently Increase Risk for Revision After Primary Total Knee Arthroplasty.

The current American Association of Hip and Knee Surgeons (AAHKS) guidelines recommend preoperative weight loss before total knee arthroplasty (TKA) in patients with body mass index (BMI) ≥40 kg/m2. However, there is a paucity of evidence on TKA outcomes after preoperative weight loss. This study therefore evaluated predictors of preoperative and postoperative BMI changes and their impact on outcomes after TKA. This is a retrospective review of 3058 primary TKAs at an academic institution from 2015 to 2019. BMI was collected on the day of surgery. Preoperative and postoperative BMI at 6 months and 1 year were also obtained. BMI change of ≥5% was considered clinically significant. Mean follow-up was 3.2 years. Patient demographics, acute postoperative outcomes, and all-cause revisions were compared between patients who gained, lost, or maintained weight using univariate and multivariable analyses. Preoperative weight loss was predictive of postoperative weight gain (P < .001), and preoperative weight gain was predictive of postoperative weight loss (P < .001). Cox regression analysis revealed that ≥5% BMI loss preoperatively increased risk for all-cause revisions (P= .030), while ≥5% BMI gain postoperatively increased risk for prosthetic joint infections (P= .016). Patients who lost significant weight both before and after surgery had the highest risk for all-cause revisions (P= .022). Weight gain postoperatively was associated with inferior outcomes. Significant weight loss before surgery led to a "rebound" in weight gain, and independently increased risk for all-cause revision. Therefore, current recommendations for weight loss before TKA in morbidly obese patients should be re-evaluated.

Minimally Invasive Intermuscular Approaches Versus Conventional Approaches in Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

BackgroundTo date, the literature has not yet revealed superiority of Minimally Invasive (MI) approaches over conventional techniques. We performed a systematic review to determine whether minimally invasive approaches are superior to conventional approaches in total hip arthroplasty for clinical and functional outcomes. We performed a meta-analysis of level 1 evidence to determine whether minimally invasive approaches are superior to conventional approaches for clinical outcomes. MethodsAll studies comparing MI approaches to conventional approaches were eligible for analysis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were adhered to throughout this study. Registries were searched using the following MeSH terms: ‘minimally invasive’, ‘muscle-sparing’, ‘THA’, ‘THR’, ‘hip arthroplasty’ and ‘hip replacement’. Locations searched included PubMed, the Cochrane Library, ClinicalTrials.gov, the European Union (EU) clinical trials register and the International Clinical Trials Registry Platform (World Health Organisation). ResultsTwenty studies were identified. There were 1,282 MI total hip arthroplasty (THAs) and 1,351 conventional THAs performed. There was no difference between MI and conventional approaches for all clinical outcomes of relevance including all-cause revision (P = .959), aseptic revision (P = .894), instability (P = .894), infection (P = .669) and periprosthetic fracture (P = .940). There was also no difference in functional outcome at early or intermediate follow-up between the two groups (P = .38). In level I studies exclusively, random-effects meta-analysis demonstrated no difference in aseptic revision (P = .461) and all other outcomes between both groups. ConclusionIntermuscular MI approaches are equivalent to conventional THA approaches when considering all-cause revision, aseptic revision, infection, dislocation, fracture rates and functional outcomes. Meta-analysis of level 1 evidence supports this claim.

Long Term Results of Two-Stage Revision for Chronic Periprosthetic Hip Infection: A Multicenter Study.

Background: Two-stage exchange arthroplasty remains the gold standard in the United States for treatment of chronic periprosthetic joint infection (PJI). Long-term reinfection rates and clinical outcomes with sufficient subject numbers remain limited. The purpose was to evaluate the long-term outcomes following two-stage exchange following hip arthroplasty. Methods: Retrospective review of 221 patients who underwent two-stage exchange hip arthroplasty for chronic PJI at three large tertiary referral institutions from 1990–2015. Outcomes including reinfection, mortality, and all-cause revision were calculated. Cumulative incidence of reinfection with death as competing factor was also calculated. Risk factors for reinfection were determined using Cox multivariate regression analysis. Results: Rate of infection eradication and all-cause revision was 88.24% and 22.6%, respectively. Overall mortality rate was 40.72%. Patients with minimum five-year follow-up (n = 129) had a success rate of 91.47% with mortality rate of 41.1%. Major risk factors for reinfection included polymicrobial infection (HR = 2.36, 95% CI: 1.08–5.14) and antibiotic resistant organism (HR = 2.36, 95% CI: 1.10–5.04). Conclusion: This is the largest series with greater than 5-year follow-up evaluating outcomes of two-stage exchange hip arthroplasty. This technique resulted in a relatively high infection eradication, however, the mortality rate is alarmingly high. Antibiotic resistant organisms appear to be highest risk factor for failure.

The use of tantalum cones and diaphyseal-engaging stems in tibial component revision: a consecutive series

IntroductionRevision knee arthroplasty presents a number of challenges, including management of bone loss. The goal in managing moderate to large bone defects is fixation that is sufficient enough to allow early weight-bearing. The purpose of this study was to describe the surgical technique and clinical and radiographic outcomes of patients treated with porous tantalum metaphyseal cones in combination with long uncemented diaphyseal-engaging stems to manage tibial bone loss in revision total knee arthroplasty (TKA).Materials and methodsThirty-six aseptic revision TKAs were performed at our institution between 2016 and 2019 by two senior authors. A single trabecular metal tantalum cone combined with a long (100 or 155 mm) press fit, diaphyseal-engaging stem was used in all cases to reconstruct metaphyseal bone defects and to augment tibial fixation. Cemented stems were excluded. The tibiofemoral angle was measured along the tibial and femoral shaft axes on the weight-bearing anteroposterior radiograph at final follow-up (range 15–56 months). All clinical and surgical complications, reoperations, and revisions of any component were recorded. Survivorship free of revision was evaluated at the time of the latest follow-up.ResultsThe mean Knee Society Score (KSS) and Knee Society Function Score (KSS-F) improved significantly from 29.7 points preoperatively (range 11–54 points) to 86 points (range 43–99 points) and from 20.4 points preoperatively (range 0–55 points) to 72.3 points (range 30–90 points) (p < 0.05), respectively. Eleven tibial constructs (30.5%) had incomplete, nonprogressive radiolucent lines (≤ 2 mm). All tibial cones demonstrated osteointegration. One patient underwent a full revision for periprosthetic joint infection, and survivorship free of any component revision was 91.7% at final follow-up.ConclusionsHybrid fixation with uncemented diaphyseal-engaging stems and porous tantalum metaphyseal cones resulted in radiographic lack of osteolysis, good clinical outcomes, and survivorship of 91.7% at a median follow-up of 33 months when considering all-cause revision as the endpoint.

The association between surgeon grade and risk of revision following total hip arthroplasty : an analysis of National Joint Registry data.

Total hip arthroplasties (THAs) are performed by surgeons at various stages in training with varying levels of supervision, but we do not know if this is safe practice with comparable outcomes to consultant-performed THA. Our aim was to examine the association between surgeon grade, the senior supervision of trainees, and the risk of revision following THA. We performed an observational study using National Joint Registry (NJR) data. We included adult patients who underwent primary THA for osteoarthritis, recorded in the NJR between 2003 and 2016. Exposures were operating surgeon grade (consultant or trainee) and whether or not trainees were directly supervised by a scrubbed consultant. Outcomes were all-cause revision and the indication for revision up to ten years. We used methods of survival analysis, adjusted for patient, operation, and healthcare setting factors. We included 603,474 THAs, of which 58,137 (9.6%) procedures were performed by a trainee. There was no association between surgeon grade and all-cause revision up to ten years (crude hazard ratio (HR) 1.00 (95% confidence interval (CI) 0.94 to 1.07); p = 0.966), a finding which persisted with adjusted analysis. Fully adjusted analysis demonstrated an association between trainees operating without scrubbed consultant supervision and an increased risk of all-cause revision (HR 1.10 (95% CI 1.00 to 1.21); p = 0.045). There was an association between trainee-performed THA and revision for instability (HR 1.14 (95% CI 1.01 to 1.30); p = 0.039). However, this was not observed in adjusted models, or when trainees were supervised by a scrubbed consultant. Within the current training system in England and Wales, appropriately supervised trainees achieve comparable THA survival to consultants. Trainees who are supervised by a scrubbed consultant achieve superior outcomes compared to trainees who are not supervised by a scrubbed consultant, particularly in terms of revision for instability. Cite this article: Bone Joint J2022;104-B(3):341-351.

High revision rates following repeat septic revision after failed one-stage exchange for periprosthetic joint infection in total knee arthroplasty.

The outcome of repeat septic revision after a failed one-stage exchange for periprosthetic joint infection (PJI) in total knee arthroplasty (TKA) remains unknown. The aim of this study was to report the infection-free and all-cause revision-free survival of repeat septic revision after a failed one-stage exchange, and to determine whether the Musculoskeletal Infection Society (MSIS) stage is associated with subsequent infection-related failure. We retrospectively reviewed all repeat septic revision TKAs which were undertaken after a failed one-stage exchange between 2004 and 2017. A total of 33 repeat septic revisions (29 one-stage and four two-stage) met the inclusion criteria. The mean follow-up from repeat septic revision was 68.2 months (8.0 months to 16.1 years). The proportion of patients who had a subsequent infection-related failure and all-cause revision was reported and Kaplan-Meier survival for these endpoints was determined. Patients were categorized according to the MSIS staging system, and the association with subsequent infection was analyzed. At the most recent follow-up, 17 repeat septic revisions (52%) had a subsequent infection-related failure and the five-year infection-free survival was 59% (95% confidence interval (CI) 39 to 74). A total of 19 underwent a subsequent all-cause revision (58%) and the five-year all-cause revision-free survival was 47% (95% CI 28 to 64). The most common indication for the first subsequent aseptic revision was loosening. The MSIS stage of the host status (p = 0.663) and limb status (p = 1.000) were not significantly associated with subsequent infection-related failure. Repeat septic revision after a failed one-stage exchange TKA for PJI is associated with a high rate of subsequent infection-related failure and all-cause revision. Patients should be counselled appropriately to manage expectations. The host and limb status according to the MSIS staging system were not associated with subsequent infection-related failure. Cite this article: Bone Joint J2022;104-B(3):386-393.

A Formal Same-Day Discharge Total Joint Arthroplasty Program May Not Be Necessary: A Propensity-Matched Cohort Study

BackgroundSame-day discharge (SDD) total joint arthroplasty (TJA) programs often have stringent selection criteria. Some patients deemed ineligible may nonetheless be discharged on the day of surgery. This study compares the outcomes between patients enrolled in our SDD TJA program who were SDD to those who did not participate in the program but were also SDD. MethodsWe retrospectively reviewed all patients who were SDD following TJA from 2015 to 2020. Patients were stratified into two cohorts based on whether they were formally enrolled in our institution’s SDD TJA program. Propensity-score matching was performed to limit confounding and independent sample t-tests or Pearson’s chi-squared tests were used to compare outcomes of interest between the matched groups. ResultsOf the 1778 patients included, 1384 (78%) completed the SDD TJA program and 394 (22%) were SDD but did not participate in the SDD TJA program. Upon 1:1 propensity-score matching, a total of 550 patients were matched for comparison. The surgical time was significantly longer for patients who did not participate in the SDD TJA program compared to those who participated in the program (109.39 vs 87.29 minutes; P < .001). Discharge disposition (P = .999), 90-day emergency department visits (P = .476), 90-day all-cause readmissions (P = .999), 90-day all-cause revisions (P = .563), and Hip disability and Osteoarthritis Outcome Scores for Joint Replacement (HOOS, JR) and Knee Injury and Osteoarthritis Outcome Scores for Joint Replacement at all time points did not significantly differ. ConclusionEnrollment in a formal SDD TJA program may not be a necessary precursor to achieving similar outcomes following TJA for patients who are SDD without formally enrolling. Therefore, a formal program may no longer be needed at an institution with well-established evidence-based protocols with strong success and an experience with value-based care. Level III EvidenceRetrospective Cohort Study.

Effects of Hospital and Surgeon Volume on Patient Outcomes After Total Joint Arthroplasty: Reported From the American Joint Replacement Registry

The purpose of this study was to evaluate outcomes and complications because it relates to surgeon and hospital volume for patients undergoing primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) using the American Joint Replacement Registry from 2012 to 2017. A retrospective study was conducted on Medicare-eligible cases of primary elective THAs and TKAs reported to the American Joint Replacement Registry database and was linked with the available Centers of Medicaid and Medicare Services claims and the National Death Index data from 2012 to 2017. Surgeon and hospital volume were defined separately based on the median annual number of anatomic-specific total arthroplasty procedures performed on patients of any age per surgeon and per hospital. Values were aggregated into separate surgeon and hospital volume tertile groupings and combined to create pairwise comparison surgeon/hospital volume groupings for hip and knee. Adjusted multivariable logistic regression analysis found low surgeon/low hospital volume to have the greatest association with all-cause revisions after THA (odds ratio [OR], 1.63, 95% confidence interval [CI], 1.41-1.89, P < 0.0001) and TKA (OR, 1.72, 95% CI, 1.44-2.06, P < 0.0001), early revisions because of periprosthetic joint infection after THA (OR, 2.50, 95% CI, 1.53-3.15, P < 0.0001) and TKA (OR, 2.18, 95% CI, 1.64-2.89, P < 0.0001), risk of early THA instability and dislocation (OR, 2.47, 95% CI, 1.77-3.46, P < 0.0001), and 90-day mortality after THA (OR, 1.72, 95% CI, 1.27-2.35, P = 0.0005) and TKA (OR, 1.47, 95% CI, 1.15-1.86, P = 0.002). Our findings demonstrate considerably greater THA and TKA complications when performed at low-volume hospitals by low-volume surgeons. Given the data from previous literature including this study, a continued push through healthcare policies and healthcare systems is warranted to direct THA and TKA procedures to high-volume centers by high-volume surgeons because of the evident decrease in complications and considerable costs associated with all-cause revisions, periprosthetic joint infection, instability, and 90-day mortality. III.

What is the Cumulative Incidence of Revision Surgery and What Are the Complications Associated With Stemmed Cementless Nonextendable Endoprostheses in Patients 18 Years or Younger With Primary Bone Sarcomas About the Knee.

Osteosarcoma and Ewing sarcoma are more common diagnoses in preadolescent and adolescent children compared with the adult population. A greater percentage of patients are treated with limb salvage and reconstruction using modular tumor endoprostheses. Implant-to-bone fixation can be cemented or cementless. Cementless tumor endoprostheses rely on biologic osteointegration for implant stability, and chemotherapy during childhood and adolescence can disturb the bone turnover rate and reduce bone mineral density, which in turn may predispose patients with uncemented endoprostheses to a high rate of revision surgeries. (1) What is the cumulative incidence of revision operations for any cause (wound dehiscence, periprosthetic fracture, hinge breakage, aseptic loosening, infection, local recurrence, implant removal, and amputation) of cementless tumor endoprostheses around the knee? (2) What is the cumulative incidence of aseptic loosening, periprosthetic fracture, hinge breakage, and infection, and what proportion of patients had other complications? (3) What was the mean limb length discrepancy (LLD) at the time of skeletal maturity? (4) What was the median Musculoskeletal Tumor Society (MSTS) score at most recent follow-up or just before implant removal/amputation if implant removal/amputation were performed? Between 2008 and 2019, we treated 328 patients younger than 18 years for a primary bone sarcoma around the knee at our institution. Of those, 138 were treated with resection and reconstruction using two different types of modular tumor endoprostheses. During this period, our general indications for an endoprosthesis were patients who were candidates for an intraarticular resection of the distal femur or proximal tibia and who were at least 10 years of age. Uncemented fixation was always preferred. Cemented fixation was only done when intraoperative press-fitting of a cementless stem was not possible. Among uncemented implants, 26 patients died before completing 2 years of follow-up with intact implants and without further surgery, three were lost to follow-up before 2 years, and four patients received implants as a secondary salvage surgery after a failed primary biologic reconstruction with a vascularized fibular bone graft, leaving 94 patients for evaluation in this retrospective study. The mean age was 15 ± 2 years and the median (interquartile range) follow-up duration was 51 months (39 to 74). We did a competing risks analysis to tally cumulative incidence of all-cause revision procedures and cumulative incidence of aseptic loosening, periprosthetic fracture, hinge breakage, and infection. Other complications, including wound dehiscence, local recurrence, and stem breakage, were characterized descriptively and ascertained by review of electronic records of a longitudinally maintained institutional database by the treating surgeons. LLD was measured by serial clinical assessments and CT scans, starting since primary salvage surgery and until the latest follow-up of every patient. For the analysis of remaining LLD, we included only patients who were skeletally immature at time of primary resection and who had reached skeletal maturity by their latest follow-up (73% [69 of 94]). Functional outcome was assessed using MSTS scores obtained from a review of electronic records of a longitudinally maintained institutional database. The 8-year cumulative incidence of revision surgery for any cause was 32% (95% confidence interval 23% to 42%). The 8-year cumulative incidence of aseptic loosening was 5% (95% CI 2% to 11%), periprosthetic fracture was 9% (95% CI 4% to 15%), hinge breakage was 19% (95% CI 12% to 28%), and infection was 7% (95% CI 3% to 14%). Other complications included wound dehiscence in 2% (2 of 94), stem breakage in 2% (2 of 94), and local recurrence in 2% (2 of 94) of patients. Stress shielding of the cortical bone around implanted stems was observed in 26% (24 of 94). The mean LLD for those who were skeletally immature at the time of primary resection and who reached skeletal maturity was 3.5 ± 2.6 cm. At latest follow-up, the median (IQR) MSTS score for all patients, excluding those who had complete implant removal or amputation, was 26 (24 to 27) of a maximum score of 30. We observed a high rate of early revision and relatively frequent complications associated with the use of cementless fixation, and although this was not a comparative study, the findings were not superior to those reported by others who have studied cemented fixation for this indication. Furthermore, there may be some disadvantages with cementless fixation, such as stress shielding. Comparative studies about fixation methods are needed. The prevalence of bushing breakage in the current study highlights the importance of future modifications in the hinge design of both types of prostheses used in this study. Patients who were skeletally immature at the time of primary surgery had a LLD no more than 5 cm at skeletal maturity; consequently, nonexpandable endoprostheses may be appropriate for some adolescent patients who have limited remaining growth, although which patients are best suited for this approach would require specific study. Level IV, therapeutic study.

Survivorship of the C-Stem total hip replacement using the “French Paradox” technique

BackgroundThis study evaluates the survivorship of the C-Stem total hip replacement, using the “French Paradox” method, at medium-term follow-up. Methods321 cemented total hip replacements in 307 patients were performed, using the canal-filling technique for the femoral stem. Survival analysis was performed for all-cause revision. The secondary outcome was aseptic loosening of the stem. ResultsRevision rate for all reasons was 2%. Overall ten-year survival was 95%. There were no revisions for femoral stem aseptic loosening. ConclusionThis is a unique study demonstrating successful outcomes of total hip replacement using the “French Paradox” technique with a triple-tapered stem.

Long-term outcome of primary total hip arthroplasty with cementless bioactive glass ceramic bottom-coated implants and highly cross-linked polyethylene: A minimum 10-year analysis

BackgroundCementless glass ceramics containing apatite and wollastonite (AW-GC) bottom-coated titanium hip implants were developed; early excellent clinical and radiographic results have been reported previously. This study aimed to investigate the long-term clinical and radiographic outcomes in detail, and the wear rate of HXLPE. MethodsWe retrospectively evaluated 99 patients (117 hips) between November 2001 and December 2007. The survival rate was estimated using the Kaplan–Meier method. Hip joint function was evaluated using the Japanese Orthopaedic Association (JOA) score. The extent of radiographic signs was determined from the radiographs performed at the last follow-up. Polyethylene wear was measured using Martell's Hip Analysis Suite. We assessed the possible factors affecting the steady-state linear wear rate. ResultsThe mean follow-up period was 14.8 ± 2.1 (10–18.6) years. The mean JOA score improved to 88.7 ± 9.4 (59–100) at the final follow-up from 47.8 ± 12.5 (17–76) before surgery. The overall survival rate with the end point of all-cause revision and wear-related revision was 99% and 100% respectively. There was no osteolysis or loosening of either the acetabular or femoral component. All hips were classified as having bone ingrowth fixation. The mean steady-state wear rate was 0.008 ± 0.025 mm/year. We found no significant correlation between the wear rate and age, body weight, body mass index, cup inclination and femoral head size. ConclusionThe combination of AW-GC bottom-coated implants and HXLPE showed excellent implant survival and wear resistance for 15 years.

Favourable outcomes of repeat one-stage exchange for periprosthetic joint infection of the hip.

One-stage exchange for periprosthetic joint infection (PJI) in total hip arthroplasty (THA) is gaining popularity. The outcome for a repeat one-stage revision THA after a failed one-stage exchange for infection remains unknown. The aim of this study was to report the infection-free and all-cause revision-free survival of repeat one-stage exchange, and to investigate the association between the Musculoskeletal Infection Society (MSIS) staging system and further infection-related failure. We retrospectively reviewed all repeat one-stage revision THAs performed after failed one-stage exchange THA for infection between January 2008 and December 2016. The final cohort included 32 patients. The mean follow-up after repeat one-stage exchange was 5.3 years (1.2 to 13.0). The patients with a further infection-related failure and/or all-cause revision were reported, and Kaplan-Meier survival for these endpoints determined. Patients were categorized according to the MSIS system, and its association with further infection was analyzed. A total of eight repeat septic revisions (25%) developed a further infection-related failure, and the five-year infection-free survival was 81% (95% confidence interval (CI) 57 to 92). Nine (28%) underwent a further all-cause revision and the five-year all-cause revision-free survival was 74% (95% CI 52 to 88). Neither the MSIS classification of the host status (p = 0.423) nor the limb status (p = 0.366) was significantly associated with further infection-related failure. Repeat one-stage exchange for PJI in THA is associated with a favourable five-year infection-free and all-cause revision-free survival. Notably, the rate of infection control is encouraging when compared with the reported rates after repeat two-stage exchange. The results can be used to counsel patients and help clinicians make informed decisions about treatment. With the available number of patients, further infection-related failure was not associated with the MSIS host or limb status. Cite this article: Bone Joint J2022;104-B(1):27-33.

Simultaneous bilateral total knee arthroplasty : similar outcomes for trainees and trainers.

AimsSimultaneous bilateral total knee arthroplasty (TKA) has been used due to its financial advantages, overall resource usage, and convenience for the patient. The training model where a trainee performs the first TKA, followed by the trainer surgeon performing the second TKA, is a unique model to our institution. This study aims to analyze the functional and clinical outcomes of bilateral simultaneous TKA when performed by a trainee or a supervising surgeon, and also to assess these outcomes based on which side was done by the trainee or by the surgeon.MethodsThis was a retrospective cohort study of all simultaneous bilateral TKAs performed by a single surgeon in an academic institution between May 2003 and November 2017. Exclusion criteria were the use of partial knee arthroplasty procedures, staged bilateral procedures, and procedures not performed by the senior author on one side and the trainee on another. Primary clinical outcomes of interest included revision and re-revision. Primary functional outcomes included the Oxford Knee Score (OKS) and patient satisfaction scores.ResultsIn total, 315 patients (630 knees) were included for analysis. Of these, functional scores were available for 189 patients (378 knees). There was a 1.9% (n = 12) all-cause revision rate for all knees. Overall, 12 knees in ten patients were revised, and both right and left knees were revised in two patients. The OKS and patient satisfaction scores were comparable for trainees and supervising surgeons. A majority of patients (88%, n = 166) were either highly likely (67%, n = 127) or likely (21%, n = 39) to recommend bilateral TKAs to a friend.ConclusionSimultaneous bilateral TKA can be used as an effective teaching model for trainees without any significant impact on patient clinical or functional outcomes. Excellent functional and clinical outcomes in both knees, regardless of whether the performing surgeon is a trainee or supervising surgeon, can be achieved with simultaneous bilateral TKA.Cite this article: Bone Jt Open 2022;3(1):29–34.

Bone-on-Bone Contact on Radiograph is not a Prerequisite for Successful Outcome in Fixed-Bearing Medial Unicompartmental Knee Arthroplasty-A 10-Year Follow-Up Study.

Patients without bone-on-bone osteoarthritis are excluded from mobile-bearing unicompartmental knee arthroplasty due to higher revision rates and poorer outcomes. However, we do not know if the same indication applies to fixed-bearing unicompartmental knee arthroplasty implants. Our study aims to compare functional outcomes and revision rates in patients with and without bone-on-bone arthritis undergoing fixed-bearing medial unicompartmental knee arthroplasty. We reviewed 153 fixed-bearing medial unicompartmental knee arthroplasties in a single institution. Patients were divided into four groups based on joint space remaining measured on preoperative radiographs. Group 1 included knees with bone-on-bone contact; group 2 included knees with less than 2 mm joint space; group 3 included knees with 2 to 4 mm joint space; group 4 included knees with more than 4 mm joint space. Patients were followed up for 10 years postoperatively and assessed using the Oxford Knee Score, the Functional Score and Knee Score from the Knee Society Clinical Rating Score, and the Short Form 36 Health Survey. There was no difference in terms of demographic data and preoperative scores. Postoperative Knee Society Functional Score was found to be lower in group 1 as compared with the other groups. There was no difference between the four groups of patients in terms of Knee Society Knee Score, Oxford Knee Score, and Physical Component Summary and Mental Component Summary Scores from the Short Form 36 Health Survey. There was no difference in terms of survivorship free from all-cause revision at a minimum of 10 years' follow-up. Symptomatic patients with varying degrees of arthritis on preoperative radiographs had comparable clinical outcomes. We conclude that symptomatic patients with clinical and radiographic evidence of medial compartment osteoarthritis of any grade can benefit from a fixed-bearing medial unicompartmental knee arthroplasty.

Cementless hydroxyapatite-coated stem with dual mobility and posterior approach in over-80 year-old patients with osteoarthritis: Rates of dislocation and periprosthetic fracture at a mean 8 years’ follow-up

BackgroundStraight cementless stems are common in primary total hip arthroplasty (THA) in the elderly, but controversial due to higher risk of loosening and periprosthetic fracture (PPF). Apart from registries, results for the Corail implant and dual mobility (DM) in over-80 years-old are not known, notably in case of systematic association to a DM cup. We therefore performed a retrospective analysis of Corail implants in patients aged≥80years at implantation for osteoarthritis of the hip, assessing 1) PPF rate and survival for cementless straight stems associated to DM cups, 2) complications, and dislocation in particular, and 3) clinical scores. HypothesisPPF and dislocation rates are low in THA with cementless straight stem associated to DM cup in patients aged≥80years. Patients methodsA retrospective study was conducted in our department for the period July 2007 to December 2012. Inclusion criteria were age≥80years, with primary THA for osteoarthritis. Exclusion criteria were revision procedure and femoral neck fracture. One hundred and twenty-eight consecutive THAs were included, in 120 patients, with a minimum 5years’ follow-up. Clinical results were assessed on Harris Hip Score (HHS) and Oxford Hip Score (OHS). Data were collected for PPF or dislocation and other complications. ResultsAt a mean 8±1 years’ follow-up (range, 5-10 years), 66 patients (55%, for 68 hips) were alive, 48 (40%, for 54 hips) had died, and 6 (5%, for 6 hips) were lost to follow-up. Median age at surgery was 83years (range, 80–93years). Mean OHS at last follow-up was 41±6 (range, 21–48) and HHS 83±14 (range, 23–100) with mean gain of 32 points (95% CI, [28–36]; p<0.001)). There were 2 cases (1.6%) of PPF, at 2 and 65months, and no dislocations or cases of aseptic loosening. There were 2 cases (1.6%) of intraoperative calcar fracture, treated by wire cerclage with immediate complete weight-bearing, without further complications. With death as a competing risk, cumulative 10-year incidence of femoral stem revision was 1.6% [95% CI: 0.4–6.5], and cumulative incidence of all-cause revision was 4.1% [95% CI: 1.7–9.7]. DiscussionIn an over-80 year-old population, primary THA with straight cementless stem and 2nd generation dual mobility cup was an effective option with low risk of PPF or dislocation after a minimum 5-year of follow-up. Level of evidenceIV; retrospective study.