Aims. The number of revision arthroplasties being performed in the elderly is expected to rise, including revision for infection. The primary aim of this study was to measure the treatment success rate for octogenarians undergoing revision total hip arthroplasty (THA) for periprosthetic joint infection (PJI) compared to a younger cohort. Secondary outcomes were complications and mortality. Methods. Patients undergoing one- or two-stage revision of a primary THA for PJI between January 2008 and January 2021 were identified. Age, sex, BMI, American Society of Anesthesiologists grade, Charlson Comorbidity Index (CCI), McPherson systemic host grade, and causative organism were collated for all patients. PJI was classified as ‘confirmed’, ‘likely’, or ‘unlikely’ according to the 2021 European Bone and Joint Infection Society criteria. Primary outcomes were complications, reoperation, re-revision, and successful treatment of PJI. A total of 37 patients aged 80 years or older and 120 patients aged under 80 years were identified. The octogenarian group had a significantly lower BMI and significantly higher CCI and McPherson systemic host grades compared to the younger cohort. Results. The majority of patients were planned to undergo two-stage revision, although a significantly higher proportion of the octogenarians did not proceed with the second stage (38.7% (n = 12) vs 14.8% (n = 16); p = 0.003). Although there was some evidence of a lower complication rate in the younger cohort, this did not reach statistical significance (p = 0.065). No significant difference in reoperation (21.6% (n = 8) vs 25.0% (n = 30); p = 0.675) or re-revision rate (8.1% (n = 3) vs 16.7% (n = 20); p = 0.288) was identified between the groups. There was no difference in treatment success between groups (octogenarian 89.2% (n = 33) vs control 82.5% (n = 99); p = 0.444). Conclusion. When compared to a younger cohort, octogenarians did not show a significant difference in complication, re-revision, or treatment success rates. However, given they are less likely to be eligible to proceed with second stage revision, consideration should be given to either single-stage revision or use of an articulated spacer to maximize functional outcomes. Cite this article: Bone Joint J 2024;106-B(8):802–807

Aims. Contemporary outcomes of primary total hip arthroplasties (THAs) with highly cross-linked polyethylene (HXLPE) liners in patients with inflammatory arthritis have not been well studied. This study examined the implant survivorship, complications, radiological results, and clinical outcomes of THA in patients with inflammatory arthritis. Methods. We identified 418 hips (350 patients) with a primary diagnosis of inflammatory arthritis who underwent primary THA with HXLPE liners from January 2000 to December 2017. Of these hips, 68% had rheumatoid arthritis (n = 286), 13% ankylosing spondylitis (n = 53), 7% juvenile rheumatoid arthritis (n = 29), 6% psoriatic arthritis (n = 24), 5% systemic lupus erythematosus (n = 23), and 1% scleroderma (n = 3). Mean age was 58 years (SD 14.8), 66.3% were female (n = 277), and mean BMI was 29 kg/m. 2. (SD 7). Uncemented femoral components were used in 77% of cases (n = 320). Uncemented acetabular components were used in all patients. Competing risk analysis was used accounting for death. Mean follow-up was 4.5 years (2 to 18). Results. The ten-year cumulative incidence of any revision was 3%, and was highest in psoriatic arthritis patients (16%). The most common indications for the 15 revisions were dislocations (n = 8) and periprosthetic joint infections (PJI; n = 4, all on disease-modifying antirheumatic drugs (DMARDs)). The ten-year cumulative incidence of reoperation was 6.1%, with the most common indications being wound infections (six cases, four on DMARDs) and postoperative periprosthetic femur fractures (two cases, both uncemented femoral components). The ten-year cumulative incidence of complications not requiring reoperation was 13.1%, with the most common being intraoperative periprosthetic femur fracture (15 cases, 14 uncemented femoral components; p = 0.13). Radiological evidence of early femoral component subsidence was observed in six cases (all uncemented). Only one femoral component ultimately developed aseptic loosening. Harris Hip Scores substantially improved (p < 0.001). Conclusion. Contemporary primary THAs with HXLPE in patients with inflammatory arthritis had excellent survivorship and good functional outcomes regardless of fixation method. Dislocation, PJI, and periprosthetic fracture were the most common complications in this cohort with inflammatory arthritis. Cite this article: Bone Joint J 2023;105-B(7):768–774

Aims. Periprosthetic femoral fracture (PPF) is a major complication following total hip arthroplasty (THA). Uncemented femoral components are widely preferred in primary THA, but are associated with higher PPF risk than cemented components. Collared components have reduced PPF rates following uncemented primary THA compared to collarless components, while maintaining similar prosthetic designs. The purpose of this study was to analyze PPF rate between collarless and collared component designs in a consecutive cohort of posterior approach THAs performed by two high-volume surgeons. Methods. This retrospective series included 1,888 uncemented primary THAs using the posterior approach performed by two surgeons (PKS, JMV) from January 2016 to December 2022. Both surgeons switched from collarless to collared components in mid-2020, which was the only change in surgical practice. Data related to component design, PPF rate, and requirement for revision surgery were collected. A total of 1,123 patients (59.5%) received a collarless femoral component and 765 (40.5%) received a collared component. PPFs were identified using medical records and radiological imaging. Fracture rates between collared and collarless components were analyzed. Power analysis confirmed 80% power of the sample to detect a significant difference in PPF rates, and a Fisher’s exact test was performed to determine an association between collared and collarless component use on PPF rates. Results. Overall, 17 PPFs occurred (0.9%). There were 16 fractures out of 1,123 collarless femoral components (1.42%) and one fracture out of 765 collared components (0.13%; p = 0.002). The majority of fractures (n = 14; 82.4%) occurred within 90 days of primary THA. There were ten reoperations for PPF with collarless components (0.89%) and one reoperation with a collared component (0.13%; p = 0.034). Conclusion. Collared femoral components were associated with significant decreases in PPF rate and reoperation rate for PPF compared to collarless components in uncemented primary THA. Future studies should investigate whether new-generation collared components reduce PPF rates with longer-term follow-up. Cite this article: Bone Joint J 2024;106-B(3 Supple A):115–120

Aims. The aim of this study was to estimate the clinical and economic burden of dislocation following primary total hip arthroplasty (THA) in England. Methods. This retrospective evaluation used data from the UK Clinical Practice Research Datalink database. Patients were eligible if they underwent a primary THA (index date) and had medical records available 90 days pre-index and 180 days post-index. Bilateral THAs were excluded. Healthcare costs and resource use were evaluated over two years. Changes (pre- vs post-THA) in generic quality of life (QoL) and joint-specific disability were evaluated. Propensity score matching controlled for baseline differences between patients with and without THA dislocation. Results. Among 13,044 patients (mean age 69.2 years (SD 11.4), 60.9% female), 191 (1.5%) had THA dislocation. Two-year median direct medical costs were £15,333 (interquartile range (IQR) 14,437 to 16,156) higher for patients with THA dislocation. Patients underwent revision surgery after a mean of 1.5 dislocations (1 to 5). Two-year costs increased to £54,088 (IQR 34,126 to 59,117) for patients with multiple closed reductions and a revision procedure. On average, patients with dislocation had greater healthcare resource use and less improvement in EuroQol five-dimension index (mean 0.24 (SD 0.35) vs 0.44 (SD 0.35); p < 0.001) and visual analogue scale (0.95 vs 8.85; p = 0.038) scores, and Oxford Hip Scores (12.93 vs 21.19; p < 0.001). Conclusion. The cost, resource use, and QoL burden of THA dislocation in England are substantial. Further research is required to understand optimal timing of revision after dislocation, with regard to cost-effectiveness and impact on QoL. Cite this article: Bone Joint J 2022;104-B(7):811–819

Aims. Although there is increasing legalization of the use of cannabis in the USA, few well-powered studies have evaluated the association between cannabis use disorder and outcomes following primary total hip arthroplasty (THA). Thus, the aim of this study was to determine whether patients who use cannabis and undergo primary THA have higher rates of in-hospital length of stay (LOS), medical complications, implant-related complications, and costs. Methods. Using an administrative database, patients with cannabis use disorder undergoing primary THA were matched to a control group in a 1:5 ratio by age, sex, and various medical comorbidities. This yielded 23,030 patients (3,842 in the study group matched with 19,188 in the control group). The variables which were studied included LOS, 90-day medical complications, two-year implant-related complications, and 90-day costs of care. Mann-Whitney U tests were used to compare LOS and costs. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of developing complications. Results. We found that patients in the study group had a significantly longer mean LOS compared with the controls (four days vs three days; p < 0.0001).The study group also had a significantly higher incidence and odds of developing medical (23.0 vs 9.8%, OR 1.6; p < 0.0001) and implant-related complications (16 vs 7.4%, OR 1.6; p < 0.0001) and incurred significantly higher mean 90-day costs ($16,938.00 vs $16,023.00; p < 0.0001). Conclusion. With the increasing rates of cannabis use, these findings allow orthopaedic surgeons and other healthcare professionals to counsel patients with cannabis use disorder about the possible outcomes following their THA, with increased hospital stays, complications, and costs. Cite this article: Bone Joint J 2021;103-B(7 Supple B):111–115

Aims. There is inconsistent evidence on whether prior spinal fusion surgery adversely impacts outcomes following total hip arthroplasty (THA). We conducted a systematic review and meta-analysis to assess the association between pre-existing spinal fusion surgery and the rate of complications following primary THA. Methods. We searched MEDLINE, Embase, Web of Science, and Cochrane Library up to October 2019 for randomized controlled trials (RCTs) and observational studies comparing outcomes of dislocation, revision, or reasons for revision in patients following primary THA with or without pre-existing spinal fusion surgery. Furthermore, we compared short (two or less levels) or long (three or more levels) spinal fusions to no fusion. Summary measures of association were relative risks (RRs) (with 95% confidence intervals (CIs)). Results. We identified ten articles corresponding to nine unique observational studies comprising of 1,992,366 primary THAs. No RCTs were identified. There were 32,945 cases of spinal fusion and 1,752,362 non-cases. Comparing prior spinal fusion versus no spinal fusion in primary THA, RRs (95% CI) for dislocation was 2.23 (1.81 to 2.74; seven studies), revision 2.14 (1.63 to 2.83; five studies), periprosthetic joint infection 1.71 (1.53 to 1.92; four studies), periprosthetic fracture 1.52 (1.28 to 1.81; three studies), aseptic loosening 1.76 (1.54 to 2.01; three studies), and any complications 2.82 (1.37 to 5.80; three studies) were identified. Both short and long spinal fusions, when compared with no fusion, were associated dislocation, revision, or reasons for revision. Conclusions. Patients with prior spinal fusion are at risk of adverse events following primary THA. Measures that reduce the risk of these complications should be considered in this high-risk population when undergoing primary THA. These patients should also be counselled appropriately around their risks of undergoing THA. Cite this article: Bone Joint J 2020;102-B(6):664–670

Arthrofibrosis is a relatively frequent complication after total knee arthroplasty. Although stiffness after total hip arthroplasty (THA), because of formation of heterotopic ossification or other causes, is not uncommon, to the authors’ best knowledge, arthrofibrosis after THA has not been described. The aim of this study is to describe the arthrofibrosis of the hip after primary total hip arthroplasty using an established clinical and histological classification of arthrofibrosis. We retrospectively examined all patients who were histologically confirmed to have arthrofibrosis after primary THA during revision surgery by examination of tissue samples in our clinic. Arthrofibrosis was diagnosed according to the histopathological SLIM-consensus classification, which defines seven different SLIM types of the periimplant synovial membrane. The SLIM type V determines the diagnosis of endoprosthesis-associated arthrofibrosis. The study population consists of 66 patients who were revised due to arthrofibrosis after primary THA. All patients had a limitation in range of motion prior to revision with a mean flexion of 90° (range from 40 to 125), mean internal rotation of 10° (range from 0 to 40) and mean external rotation of 20° (range from 0 to 50). All patients had histological SLIM type V arthrofibrosis, corresponding to endoprosthesis-associated arthrofibrosis. Histological examination revealed that seven patients (10.6%) had particle-induced and 59 patients (89.4%) had non-particle-induced arthrofibrosis. This is the first decription of endoprosthetic-associated arthrofibrosis after primary THA on the basis of a well-established histological classification. Our study results could enable new therapeutic and diagnostic opportunities in patients with such an arthrofibrosis. Surgeons should keep arthrofibrosis as a possible cause for stiffness and pain after primary total hip arthroplasty in mind. Level of evidence Diagnostic study, Level of Evidence IV. Thorsten Gehrke and Lara Althaus contributed equally to the writing of this manuscript

Aims. The Forgotten Joint Score-12 (FJS-12) is a validated patient-reported outcome measure (PROM) tool designed to assess artificial prosthesis awareness during daily activities following total hip arthroplasty (THA). The patient-acceptable symptom state (PASS) is the minimum cut-off value that corresponds to a patient’s satisfactory state-of-health. Despite the validity and reliability of the FJS-12 having been previously demonstrated, the PASS has yet to be clearly defined. This study aims to define the PASS of the FJS-12 following primary THA. Methods. We retrospectively reviewed all patients who underwent primary elective THA from 2019 to 2020, and answered both the FJS-12 and the Hip Disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS, JR) questionnaires one-year postoperatively. HOOS, JR score was used as the anchor to estimate the PASS of FJS-12. Two statistical methods were employed: the receiver operating characteristic (ROC) curve point, which maximized the Youden index; and 75th percentile of the cumulative percentage curve of patients who had the HOOS, JR score difference larger than the cut-off value. Results. This study included 780 patients. The mean one-year FJS-12 score was 65.42 (SD 28.59). The mean one-year HOOS, JR score was 82.70 (SD 16.57). A high positive correlation between FJS-12 and HOOS, JR was found (r = 0.74; p<0.001), making the HOOS, JR a valid external anchor. The threshold score of the FJS-12 that maximized the sensitivity and specificity for detecting a PASS was 66.68 (area under the curve = 0.8). The cut-off score value computed with the 75th percentile approach was 92.20. Conclusion. The PASS threshold for the FJS-12 at one year following primary THA was 66.68 and 92.20 using the ROC curve and 75th percentile approaches, respectively. These values can be used to achieve consensus about meaningful postoperative improvement to maximize the utility of the FJS-12 to evaluate and counsel patients undergoing THA. Cite this article: Bone Jt Open 2022;3(4):307–313

Aims

The aim of this study was to examine whether socioeconomic status (SES) is associated with a higher risk of infections following total hip arthroplasty (THA) at 30 and 90 days.

Aims. The aim of this study was to report the long-term follow-up of cemented short Exeter femoral components when used in primary total hip arthroplasty (THA). Methods. We included all primary 394 THAs with a cemented short Exeter femoral component (≤ 125 mm) used in our tertiary referral centre between October 1993 and December 2021. A total of 83 patients (21%) were male. The median age of the patients at the time of surgery was 42 years (interquartile range (IQR) 30 to 55). The main indication for THA was a childhood hip disease (202; 51%). The median follow-up was 6.7 years (IQR 3.1 to 11.0). Kaplan-Meier survival analyses were performed to determine the rates of survival with femoral revision for any indication, for septic loosening, for fracture of the femoral component and for aseptic loosening as endpoints. The indications for revision were evaluated. Fractures of the femoral component were described in detail. Results. The 20-year rate of survival was 85.4% (95% confidence interval (CI) 73.9 to 92.0) with revision for any indication, 96.2% (95% CI 90.5 to 98.5) with revision for septic loosening and 92.7% (95% CI 78.5 to 97.6) with revision for fracture of the femoral component. No femoral components were revised for aseptic loosening. There were 21 revisions of the femoral component; most (seven) as part of a two-stage management of infection. Fracture of the femoral component occurred in four THAs (1.0%) at 6.6, 11.6, 16.5, and 18.2 years of follow-up, respectively. Three of these were transverse fractures and occurred at the level of the lesser trochanter. In one THA, there was a fracture of the neck of the component. Conclusion. THAs using cemented short Exeter femoral components showed acceptable rates of survival of the femoral component at long-term follow-up, in this young cohort of patients. Although fracture is a rare complication of these components, surgeons should be aware of their incidence and possible risk factors. Cite this article: Bone Joint J 2024;106-B(3 Supple A):137–142

Abstract. Background. Although tantalum is a well recognised implant material used for revision arthroplasty, little is known regarding the use of the same in primary total hip arthroplasty. Methods. A literature search was performed to find all relevant clinical studies until March 2020, which then underwent a further selection criteria. The inclusion criteria was set as follows: Reporting on human patients undergoing primary total hip arthroplasty; Direct comparison between tantalum acetabular cups with conventional acetabular cups. for use in primary total hip arthroplasty; Radiological evaluation (cup migration, osteointegration); Clinical (functional scores, need for subsequent revision, patient-reported outcomes; Post-operative complications; Reporting findings in the English Language. After a thorough search a total of six studies were included in the review. The primary outcome. measures were clinical outcomes, implant migration, change in bone mineral density and rate of revision and infection. Results. Tantalum was found superior to titanium with regards to fewer radiolucencies, survivorship, osteointegration, decreased osteolysis and mechanical loosening. No significant difference in radioisometric analysis, bone mineral density or Harris Hip Score was found. Revision and infection rates were found to be significantly lower in tantalum group at 10 years from pooled data of national joint registry. Conclusion. The use of tantalum can be reserved for cases of high risk of failure or mechanical loosening, where failure of a contralateral joint occurred as it carries lower risk of failure and infection. Further studies with longer follow-up would be useful in drawing further conclusions

Aim. Prosthetic joint infection (PJI) is a serious complication following total hip arthroplasty (THA) entailing increased mortality, decreased quality of life, and high healthcare costs. In 2009 a nationwide, multidisciplinary infection control program was launched in Sweden, PRISS, which aimed to reduce the PJI burden by 50%. The primary aim was to investigate whether the PRISS project reduced PJI incidence after primary THA; the secondary aim was to evaluate other possible benefits of PRISS, such as shorter time to diagnosis. Method. We obtained data on patients undergoing primary THA in Sweden (n = 45,723 patients, 49,946 THAs), 2012–2014. Using personal identity numbers, this cohort was matched with the Swedish Prescribed Drug Registry. Medical records of patients with ≥4 weeks antibiotic consumption were reviewed to verify PJI diagnosis (n = 2240, 2569 THAs). Results. The cumulative incidence of PJI following the PRISS project was 1.2% [95% CI 1.1–1.3] as compared to 0.9% [95% CI 0.8–1.0] before. Cox regression models for the PJI incidence post PRISS indicates there were no statistical significance difference versus pre PRISS (HR 1.1 [95% CI 0.9–1.3]. There were similar time to PJI diagnosis after the PRISS project 24 vs 23 days (p=0.5). Conclusions. Despite the comprehensive nationwide PRISS project, Swedish PJI incidence was higher after the project and time to diagnosis remained unchanged. Factors contributing to PJI, such as increasing obesity, higher ASA class, and more fractures as indications, explain the PJI increase among primary THA patients

Periprosthetic femur fracture (PFF) is a major complication following total hip arthroplasty (THA) that carries significant morbidity, mortality, and economic burden. Currently, uncemented stems are highly preferred in primary THA, but have been associated with higher risk of PFF compared to cemented stems. The use of collared stems in uncemented primary THA has shown promise in reducing PFF rates postoperatively. This retrospective study included 2,294 uncemented primary THAs using the posterior approach performed by two attending surgeons from January 2016 to December 2022. Both surgeons switched from a collarless femoral stem design to a collared design in May 2020. Data was collected regarding stem design, frequency of PFF, and requirement for revision surgery. Periprosthetic fractures were identified and confirmed using medical records and/or radiographic imaging. Fracture rates and percentages between collared and collarless stems were then analyzed. A Fisher's Exact Test was performed to determine if there was a significant association between collared and collarless stem use on PFF rates. A total of 2,294 uncemented primary THAs performed by 2 surgeons were eligible for analysis. 903 (39.4%) patients received a collared stem, and 1,391 (60.6%) patients received a collarless stem. In total, 14 (0.6%) PFFs occurred over the study period. There was 1 fracture (0.1%) out of 903 collared stems, and 13 fractures (0.9%) out of 1,391 collarless stems (p = 0.012). Collared stems were associated with a significant decrease in PFF rate when compared to collarless stems in uncemented primary THA. Future studies are encouraged to continue to investigate PFF and other complication rates with the use of a collared stem design

Aims. The aim of this study was to analyze the effect of a lateral rim mesh on the survival of primary total hip arthroplasty (THA) in young patients, aged 50 years or younger. Patients and Methods. We compared a study group of 235 patients (257 hips) who received a primary THA with the use of impaction bone grafting (IBG) with an additional lateral rim mesh with a group of 306 patients (343 hips) who received IBG in the absence of a lateral rim mesh during the same period from 1988 to 2015. In the mesh group, there were 74 male and 183 female patients, with a mean age of 35 years (13 to 50). In the no-mesh group, there were 173 male and 170 female patients, with a mean age of 38 years (12.6 to 50). Cox regression analyses were performed to study the effect of a lateral rim mesh on acetabular component survival. Kaplan–Meier analyses with 95% confidence intervals (CIs) were performed to estimate the survival of the acetabular implant. Results. The hazard ratio for the use of lateral rim mesh, adjusted for potential confounders, for acetabular revision for any reason was 0.50 (95% CI 0.13 to 1.93; p = 0.31) and for acetabular revision for aseptic loosening was 0.29 (95% CI 0.020 to 4.04; p = 0.35). The Kaplan–Meier analysis showed a ten-year survival for aseptic loosening of the acetabular of 98% (95% CI 95 to 100, n = 65 at risk) in the mesh group and 94% (89 to 98, n = 76 at risk) in the no-mesh group. The 15-year survival for aseptic acetabular loosening was 90% (81 to 100, n = 35 at risk) in the mesh group and 85% (77 to 94, n = 45 at risk) in the no-mesh group (p = 0.23). Conclusion. This study shows that the use of a lateral rim mesh in primary THA in young patients is not associated with a higher risk of revision of the acetabular component. Therefore, we consider a lateral rim mesh combined with IBG to be effective in reconstructing segmental acetabular defects in primary THA

Aims. As our population ages, the number of octogenarians who will require a total hip arthroplasty (THA) rises. In a value-based system where operative outcomes are linked to hospital payments, it is necessary to assess the outcomes in this population. The purpose of this study was to compare outcomes of elective, primary THA in patients ≥ 80 years old to those aged < 80. Methods. A retrospective review of 10,251 consecutive THA cases from 2011 to 2019 was conducted. Patient-reported outcome (PRO) scores (Hip disability and Osteoarthritis Outcome Score (HOOS)), as well as demographic, readmission, and complication data, were collected. Results. On average, the younger cohort (YC, n = 10,251) was a mean 61.60 years old (SD 10.71), while the older cohort (OC, n = 609) was 84.25 years old (SD 3.02) (p < 0.001). The OC had greater surgical risk based on their higher mean American Society of Anesthesiologists (ASA) scores (2.74 (SD 0.63) vs 2.30 (SD 0.63); p < 0.001) and Charlson Comorbidity Index (CCI) scores (6.26 (SD 1.71) vs 3.87 (SD 1.98); p < 0.001). While the OC stayed in the hospital longer than the YC (mean 3.5 vs 2.5 days; p < 0.001), there were no differences in 90-day emergency visits (p = 0.083), myocardial infarctions (p = 0.993), periprosthetic joint infections (p = 0.214), dislocations (p = 0.993), or aseptic failure (p = 0.993). The YC was more likely to be readmitted within 90 days (3.88% vs 2.18%, Β = 0.57; p = 0.048). There were no observed differences in 12-week (p = 0.518) or one-year (p = 0.511) HOOS scores. Conclusion. Although patients ≥ 80 years old have a greater number of comorbidities than younger patients, they had equivalent perioperative complication rates and PRO scores. This study demonstrates the safety and success of elective THA in octogenarians. Cite this article: Bone Jt Open 2021;2(7):535–539

Detection of clinical situations are the most difficult for primary THA and factors which determine the complexity. Results of 2368 primary THA performed by one surgeon in 1923 patients with various hip pathologies from 2004 to 2016 were analyzed. The time of the surgery, the bloodloss, the features of the surgical technique, the implants used, and the incidence of complications and revisions were assessed and X-ray analysis was performed. Difficult cases of primary hip arthroplasty include severe dysplasia (types B2, C1, and C2 according to the Hartofilakidis classification), post-traumatic segmental acetabular defects and pelvic discontinuity, protrusio acetabuli, iatrogenic bone ankylosis and consequences of proximal femur fractures with significant shortening of the limb. X-ray signs of difficulty included an interruption of the Shenton line of 2 cm or more (except for acute fractures of proximal femur), the femoral neck-shaft angle less than 100°, and the horizontal distance from Kohler line to center of rotation less than 20% of the diameter of the femoral head. An additional burdening factor is the previous surgical interventions on the hip joint. The ten-year survival rate for standard cases was 94.9%, and for complex cases − 92.3%. The odds ratio development of complications in complex cases compared to standard cases is OR = 8.402 (95% CI from 4.614 to 15.300). In standard cases mean HHS increased from 42.9 points before surgery to 95.3 after surgery. In complex cases mean HHS before surgery was 38.9 and after surgery improved to 81.6 points, p <0.001. The complexity of the operation cannot be determined on the basis of only the etiological factor, it is necessary to take into account the severity of anatomical changes

Aims. The Exeter V40 femoral stem is the most implanted stem in the National Joint Registry (NJR) for primary total hip arthroplasty (THA). In 2004, the 44/00/125 stem was released for use in ‘cement-in-cement’ revision cases. It has, however, been used ‘off-label’ as a primary stem when patient anatomy requires a smaller stem with a 44 mm offset. We aimed to investigate survival of this implant in comparison to others in the range when used in primary THAs recorded in the NJR. Methods. We analyzed 328,737 primary THAs using the Exeter V40 stem, comprising 34.3% of the 958,869 from the start of the NJR to December 2018. Our exposure was the stem, and the outcome was all-cause construct revision. We stratified analyses into four groups: constructs using the 44/00/125 stem, those using the 44/0/150 stem, those including a 35.5/125 stem, and constructs using any other Exeter V40 stem. Results. In all 328,737 THAs using an Exeter V40 stem, the revision estimate was 2.8% (95% confidence interval (CI) 2.7 to 2.8). The 44/00/125 stem was implanted in 2,158 primary THAs, and the ten-year revision estimate was 4.9% (95% CI 3.6 to 6.8). Controlling for age, sex, year of operation, indication, and American Society of Anesthesiologists grade demonstrated an increased overall hazard of revision for constructs using the 44/00/125 stem compared to constructs using other Exeter V40 femoral stems (hazard ratio 1.8 (95% CI 1.4 to 2.3)). Conclusion. Although the revision estimate is within the National Institute for Health and Care Excellence ten-year benchmark, survivorship of constructs using the 44/00/125 stem appears to be lower than the rest of the range. Adjusted analyses will not take into account ‘confounding by indication’, e.g. patients with complex anatomy who may have a higher risk of revision. Surgeons and patients should be reassured but be aware of the observed increased revision estimate, and only use this stem when other implants are not suitable. Cite this article: Bone Joint J 2023;105-B(5):504–510

Primary total hip replacement (THR) is a successful and common operation which orthopaedic trainees must demonstrate competence in prior to completion of training. This study aimed to determine the impact of operating surgeon grade and level of supervision on the incidence of 1-year patient mortality and all-cause revision following elective primary THR in a large UK training centre. National Joint Registry (NJR) data for all elective primary THR performed in a single University Teaching Hospital from 2005–2020 were used, with analysis performed on the 15-year dataset divided into 5-year temporal periods (B1 2005–2010, B2 2010–2015, B3 2015–2020). Outcome measures were mortality and revision surgery at one year, in relation to lead surgeon grade, and level of supervision for trainee-led operations. 9999 eligible primary THR were undertaken, of which 5526 (55.3%) were consultant led (CL), and 4473 (44.7%) trainees led (TL). Of TL, 2404 (53.7%) were non-consultant supervised (TU), and 2069 (46.3%) consultant supervised (TS). The incidence of 1-year patient mortality was 2.05% (n=205), and all-cause revision was 1.11% (n=111). There was no difference in 1-year mortality between TL (n=82, 1.8%) and CL (n=123, 2.2%) operations (p=0.20, OR 0.78, CI 0.55–1.10). The incidence of 1-year revision was not different for TL (n=56, 1.3%) and CL (n=55, 1.0%) operations (p=0.15, OR 1.37, CI 0.89–2.09). Overall, there was no temporal change for either outcome measure between TL or CL operations. A significant increase in revision within 1-year was observed in B3 between TU (n=17, 2.7%) compared to CL (n=17, 1.0%) operations (p=0.005, OR 2.81, CI 1.35–5.87). We found no difference in 1-year mortality or 1-year all-cause revision rate between trainee-led primary THR and consultant-led operations over the entire fifteen-year period. However, unsupervised trainee led THR in the most recent 5-year block (2015–2020) has a significantly increased risk of early revision, mainly due to instability and prosthetic joint infection. This suggests that modern surgical training is having a detrimental effect on THR patient outcomes. More research is needed to understand the reasons if this trend is to be reversed

Total hip arthroplasty (THA) is one of the most successful and effective treatments for advanced hip osteoarthritis (OA). Over the last 5 years, Canada has seen a 17.8% increase in the number of hip replacements performed annually, and that number is expected to grow along with the aging Canadian population. However, the rise in THA surgery is associated with an increased number of patients at risk for the development of an infection involving the joint prosthesis and adjacent deep tissue – periprosthetic joint infections (PJI). Despite improved hygiene protocols and novel surgical strategies, PJI remains a serious complication. No previous population-based studies has investigated PJI risk factors using a time-to-event approach and none have focused exclusively on patients undergoing THA for primary hip OA. The purpose of this study is to determine risk factors for PJI after primary THA for OA using a large population-based database collected over 15 years. Our secondary objective is to determine the incidence of PJI, the time to PJI following primary THA, and if PJI rates have changed in the past 15 years. We performed a population-based cohort study using linked administrative databases in Ontario, Canada in accordance with RECORD and STROBE guidelines. All primary total hip replacements performed for osteoarthritis in patients aged 55 or older between January 1st 2002 – December 31st 2016 in Ontario, Canada were identified. Periprosthetic joint infection as the cause for revision surgery was identified with the International Classification of Diseases, 10th Edition (ICD-10), Clinical Modification diagnosis code T84.53 in any component of the healthcare data set. Data were obtained from the Institute for Clinical Evaluative Sciences (ICES). Demographic data and outcomes are summarized using descriptive statistics. We used a Cox proportional hazards model to analyze the effect of surgical factors and patient factors on the risk of developing PJI. Surgical factors include the approach, use of bone graft, use of cement, and the year of surgery. Patient factors include sex, age at surgery, income quintile and rurality (community vs. urban). We compared the 1,2,5 and 10 year PJI rates for patients undergoing THA each year of our cohort with the Cochran-Armitage test. Less than 0.1% of data were missing from all fields except for rurality which was lacking 0.3% of data. A total of 100,674 patients aged 55 or older received a primary total hip arthroplasty for osteoarthritis from 2002–2016. We identified 1034 cases of revision surgery for prosthetic joint infection for an overall PJI rate of 1.03%. When accounting for patients censored at final follow-up, the cumulative incidence for PJI is 1.44%. Our Cox proportional hazards model revealed that male sex, Type II diabetes mellitus, discharge to convalescent care, and having both hips replaced during one's lifetime were associated with increased risk of developing PJI following primary THA. Importantly, the time adjusted risk for PJI was equal for patients operated within the past 5 years, 6–10 years ago, or 11–15 years ago. The surgical approach, use of bone grafting or cement were not associated with increased risk of infection. PJI rates have not changed significantly over the past 15 years. One, two, five and ten-year PJI rates were similar for patients undergoing THA in all qualifying years. Analysis of a population-based cohort of 100,674 patients has shown that the risk of developing PJI following primary THA has not changed over 15 years. The surgical approach, use of bone grafting or cement were not associated with increased risk of infection. Male sex, Type II diabetes Mellitus and discharge to a rehab facility are associated with increased risk of PJI. As the risk of PJI has not changed in 15 years, an appropriately powered trial is warranted to determine interventions that can improve infection rate after THA

The benefit of using acetabular screws in primary total hip arthroplasty (THA) has been questioned in recent years. The disadvantages of using screws include increased operative time, risk of injury to surrounding neurovascular structures and metal ware breakage. Recent large registry studies have reported that screws do not confer a protective effect against acetabular loosening or the presence of osteolysis. Other studies have even described an increased risk of aseptic acetabular loosening with the selective use of screws. We report findings from a multicentre cohort study. This large cohort study compared clinical outcomes between primary acetabular components that were inserted with and without screws. Independent variables included the presence (or absence) of screws, the total number of screws used and the cumulative screw length (CSL). Outcome measures included all-cause revision, acetabular component revision and acetabular component loosening. Statistical software (Stata/IC 13.1 for Mac [64-bit Intel]) was used to conduct all statistical analyses. A p-value < 0 .05 taken to be significant. There were 4,583 THAs performed in total. Screws were used in 15.9% (n=733). At a mean follow-up of 5.2 years, the all-cause revision rate in the screw cohort was 1.5% compared to 0.83% in the no screw cohort (p=0.085). There was no difference in acetabular component revision rates for screws (3/733, 0.41%) versus no screws (12/3,850, 0.31%) (p=0.439). The rate of acetabular loosening noted during the time of revision surgery was significantly higher when screws were used in the index procedure (2/733, 0.2%) compared to the no screw cohort (1/3,850, 0.02%) (p=0.017). There was no difference in outcomes when stratifying by the number of screws used or the cumulative screw length. Primary acetabular components do not require screws for fixation. All cause revision rates and acetabular component revision rates are comparable for the screw and the no screw cohorts. The rate of acetabular component loosening, as observed during revision surgery, is significantly higher when screws are used in the index total hip replacement

Aims. The aim of this study was to determine the outcome of all primary total hip arthroplasties (THAs) and their subsequent revision procedures in patients aged under 50 years performed at our institution. Methods. All 1,049 primary THAs which were undertaken in 860 patients aged under 50 years between 1988 and 2018 in our tertiary care institution were included. We used cemented implants in both primary and revision surgery. Impaction bone grafting was used in patients with acetabular or femoral bone defects. Kaplan-Meier analyses were used to determine the survival of primary and revision THA with the endpoint of revision for any reason, and of revision for aseptic loosening. Results. The mean age of the patients at the time of the initial THA was 38.6 years (SD 9.3). The mean follow-up of the THA was 8.7 years (2.0 to 31.5). The rate of survival for all primary THAs, acetabular components only, and femoral components only at 20 years’ follow-up with the endpoint of revision for any reason, was 66.7% (95% confidence interval (CI) 60.5 to 72.2), 69.1% (95% CI 63.0 to 74.4), and 83.2% (95% CI 78.1 to 87.3), respectively. A total of 138 revisions were performed. The mean age at the time of revision was 48.2 years (23 to 72). Survival of all subsequent revision procedures, revised acetabular, and revised femoral components at 15 years’ follow-up with the endpoint of revision for any reason was 70.3% (95% CI 56.1 to 80.7), 69.7% (95% CI 54.3 to 80.7), and 76.2% (95% CI 57.8 to 87.4), respectively. A Girdlestone excision arthroplasty was required in six of 860 patients (0.7%). Conclusion. The long-term outcome of cemented primary and subsequent revision THA is promising in these young patients. We showed that our philosophy of using impaction bone grafting in patients with acetabular and femoral defects is a very suitable option when treating young patients. Surgeons should realize that knowledge of the outcome of subsequent revision surgery, which is inevitable in young patients, must be communicated to this group of patients prior to their initial THA. Cite this article: Bone Joint J 2022;104-B(3):368–375

To estimate the clinical and economic burden of primary total hip arthroplasty (THA) dislocation in England. Retrospective propensity score-matched evaluation of patients with and without dislocation following primary THA using the UK Clinical Practice Research Datalink linked and Hospital Episode Statistics datasets with a 2-year follow-up. 13,044 patients with total hip replacements met the inclusion criteria (mean age 69.2, 60.9% female) of which 154 (1.18%) suffered at least one postoperative hip dislocation. The mean number of dislocations per patient was 1.44 with a maximum of 4. Approximately one-third of the patients with dislocation (32.5%) had more than one dislocation. Among patients with a hip dislocation 148 patients (96.7%) had at least one closed reduction and 20 patients (13.1%) had revision surgery. Two-year median direct medical costs were £14,748 (95% confidence interval [CI] £12,028 to £20,638) higher with vs. without dislocation (+227%). On average, patients with a dislocation had significantly greater healthcare resource utilization and significantly less improvement in EuroQol-5D (EQ-5D) index (0.24 vs. 0.45; p<0.001) and Visual Analogue Scale (VAS) (1.58 vs. 11.23; p=0.010) scores and Oxford Hip Scores (13.02 vs. 21.98; p<0.001). This is the first study to estimate the economic burden of dislocation in the UK throughout the entire patient pathway. Dislocation following total hip replacement is a costly complication, both in terms of economic costs and to the functional quality of life of the patient. Efforts to reduce the risks of dislocation should remain at the forefront of hip research

Introduction. With the widespread legalization of cannabis across the United States, well-powered studies evaluating the impact of cannabis use disorder on outcomes following primary total hip arthroplasty are warranted. Therefore, the aim of this study was to determine whether cannabis use disorder has an effect on patients who undergo primary hip arthroplasty in terms of: 1) hospital lengths of stay (LOS); 2) medical complications; 3) implant-related complications; and 4) costs of care. Methods. Using an administrative database, patients who underwent primary total hip arthroplasty and had cannabis use disorder were matched to a cohort who did not in a 1:5 ratio by age, sex, and various medical comorbidities. This yielded 44,154 patients; 7,361 who had cannabis use disorder and 36,793 who did not. Variables for analysis included postoperative LOS, 90-day medical complications, 2-year implant-related complications, and 90-day costs of care. Mann-Whitney-U tests were used to compare LOS and costs. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of developing complications. A p-value less than 0.005 was considered statistically significant. Results. The study found that patients who had cannabis use disorder had significantly longer in-hospital LOS (4 vs. 3 days, p<0.0001) compared to the matched cohort. Additionally, study patients were found to have significantly higher incidences and odds of developing medical (11.23 vs. 4.82%; OR: 1.47, p<0.0001) and implant-related complications (18.14 vs. 8.60%; OR: 1.50, p<0.0001). Moreover, patients who had cannabis use disorder incurred significantly higher 90-day episode of care costs ($24,585.96 vs. $23,725.93, p<0.0001). Conclusions. With the growing rates of cannabis use, this study can allow orthopaedists and other healthcare professionals to educate cannabis use disorder on the possible outcomes following their total hip arthroplasty. It should be appreciated that cannabis use disorder is associated with longer hospital stays, increased complication rates, and higher costs following primary THA

Aims. The aim of this study was to investigate whether the use of antibiotic-loaded bone cement influenced the risk of revision surgery after primary total hip arthroplasty (THA) for osteoarthritis. Methods. The study involved data collected by the National Joint Registry (NJR) for England and Wales, Northern Ireland and the Isle of Man between 1 September 2005 and 31 August 2017. Cox proportional hazards were used to investigate the association between use of antibiotic-loaded bone cement and the risk of revision due to prosthetic joint infection (PJI), with adjustments made for the year of the initial procedure, age at the time of surgery, sex, American Society of Anesthesiologists (ASA) grade, head size, and body mass index (BMI). We looked also at the association between use of antibiotic-loaded bone cement and the risk of revision due to aseptic loosening or osteolysis. Results. The cohort included 418,857 THAs of whom 397,896 had received antibiotic-loaded bone cement and 20,961 plain cement. After adjusting for putative confounding factors, the risk of revision for PJI was lower in those in whom antibiotic-loaded bone cement was used (hazard ration (HR) 0.79; 95% confidence interval (CI) 0.64 to 0.98). There was also a protective effect on the risk of revision due to aseptic loosening or osteolysis, in the period of > 4.1 years after primary THA, HR 0.57, 95% CI 0.45, 0.72. Conclusion. Within the limits of registry analysis, this study showed an association between the use of antibiotic-loaded bone cement and lower rates of revision due to PJI. The findings support the continued use of antibiotic-loaded bone cement in cemented THA. Cite this article: Bone Joint J 2020;102-B(8):997–1002

Objectives. High failure rates of metal-on-metal hip arthroplasty implants have highlighted the need for more careful introduction and monitoring of new implants and for the evaluation of the safety of medical devices. The National Joint Registry and other regulatory services are unable to detect failing implants at an early enough stage. We aimed to identify validated surrogate markers of long-term outcome in patients undergoing primary total hip arthroplasty (THA). Methods. We conducted a systematic review of studies evaluating surrogate markers for predicting long-term outcome in primary THA. Long-term outcome was defined as revision rate of an implant at ten years according to National Institute of Health and Care Excellence guidelines. We conducted a search of Medline and Embase (OVID) databases. Separate search strategies were devised for the Cochrane database and Google Scholar. Each search was performed to include articles from the date of their inception to June 8, 2015. Results. Our search strategy identified 1082 studies of which 115 studies were included for full article review. Following review, 17 articles were found that investigated surrogate markers of long-term outcome. These included one systematic review, one randomised control trial (RCT), one case control study and 13 case series. Validated surrogate markers included Radiostereometric Analysis (RSA) and Einzel-Bild-Röntgen-Analyse (EBRA), each measuring implant migration and wear. We identified five RSA studies (one systematic review and four case series) and four EBRA studies (one RCT and three case series). Patient Reported Outcome Measures (PROMs) at six months have been investigated but have not been validated against long-term outcomes. Conclusions. This systematic review identified two validated surrogate markers of long-term primary THA outcome: RSA and EBRA, each measuring implant migration and wear. We recommend the consideration of RSA in the pre-market testing of new implants. EBRA can be used to investigate acetabular wear but not femoral migration. Further studies are needed to validate the use of PROMs for post-market surveillance. Cite this article: T. T. Malak, J. A. J. Broomfield, A. J. R. Palmer, S. Hopewell, A. Carr, C. Brown, D. Prieto-Alhambra, S. Glyn-Jones. Surrogate markers of long-term outcome in primary total hip arthroplasty: A systematic review. Bone Joint Res 2016;5:206–214. DOI: 10.1302/2046-3758.56.2000568

Aims. Septic arthritis of the hip often leads to irreversible osteoarthritis (OA) and the requirement for total hip arthroplasty (THA). The aim of this study was to report the mid-term risk of any infection, periprosthetic joint infection (PJI), aseptic revision, and reoperation in patients with a past history of septic arthritis who underwent THA, compared with a control group of patients who underwent THA for OA. Methods. We retrospectively identified 256 THAs in 244 patients following septic arthritis of the native hip, which were undertaken between 1969 and 2016 at a single institution. Each case was matched 1:1, based on age, sex, BMI, and year of surgery, to a primary THA performed for OA. The mean age and BMI were 58 years (35 to 84) and 31 kg/m. 2. (18 to 48), respectively, and 100 (39%) were female. The mean follow-up was 11 years (2 to 39). Results. The ten-year survival free of any infection was 91% and 99% in the septic arthritis and OA groups, respectively (hazard ratio (HR) = 13; p < 0.001). The survival free of PJI at ten years was 93% and 99% in the septic arthritis and OA groups, respectively (HR = 10; p = 0.002). There was a significantly higher rate of any infection at ten years when THA was undertaken within five years of the diagnosis of septic arthritis compared with those in whom THA was undertaken > five years after this diagnosis was made (14% vs 5%, respectively; HR = 3.1; p = 0.009), but there was no significant difference in ten-year survival free of aseptic revision (HR = 1.14; p = 0.485). The mean Harris Hip Scores at two and five years postoperatively were significantly lower in the septic arthritis group compared with the OA group (p = 0.001 for both). Conclusion. There was a ten-fold increased risk of PJI in patients with a history of septic arthritis who underwent THA compared with those who underwent THA for OA with a ten-year cumulative incidence of 7%. The risk of any infection had a strong downward trend as the time interval between the diagnosis of septic arthritis and THA increased, highlighted by a 3.1-fold higher risk when THAs were performed within five years of the diagnosis being made. Cite this article: Bone Joint J 2022;104-B(2):227–234

The last two decades have seen remarkable technological advances in total hip arthroplasty (THA) implant design. Porous ingrowth surfaces and highly crosslinked polyethylene (HXLPE) have been expected to dramatically improve implant survivorship. The purpose of the present study was to evaluate survival of contemporary cementless acetabular components following primary THA. 16,421 primary THAs performed for osteoarthritis between 2000 and 2019 were identified from our institutional total joint registry. Patients received one of 12 contemporary cementless acetabular designs with HXLPE liners. Components were grouped based on ingrowth surface into 4 categories: porous titanium (n=10,952, mean follow-up 5 years), porous tantalum (n=1223, mean follow-up 5 years), metal mesh (n=2680, mean follow-up 6.5 years), and hydroxyapatite (HA) coated (n=1566, mean follow-up 2.4 years). Kaplan-Meier analyses were performed to assess the survivorship free of acetabular revision. A historical series of 182 Harris-Galante-1 (HG-1) acetabular components was used as reference. The 15-year survivorship free of acetabular revision was >97% for all 4 contemporary cohorts. Compared to historical control, porous titanium (HR 0.06, 95% CI 0.02–0.17, p<0.001), porous tantalum (HR 0.09, 95%CI 0.03–0.29, p<0.001), metal mesh (HR 0.11, 95%CI 0.04–0.31, p<0.001), and HA-coated (HR 0.14, 95%CI 0.04–0.48, p=0.002) ingrowth surfaces had significantly lower risk of any acetabular revision. There were 16 cases (0.1%) of acetabular aseptic loosening that occurred in 8 (0.07%) porous titanium, 5 (0.2%) metal mesh, and 3 (0.2%) HA-coated acetabular components. 7 of the 8 porous titanium aseptic loosening cases occurred in one known problematic design. There were no cases of aseptic loosening in the porous tantalum group. Modern acetabular ingrowth surfaces and HXLPE liners have improved on historical results at the mid-term. Contemporary designs have extraordinarily high revision-free survivorship, and aseptic loosening is now a rare complication. At mid-term follow-up, survivorship of contemporary uncemented acetabular components is excellent and aseptic loosening occurs in a very small minority of patients

With the introduction of highly crosslinked polyethylene (HXLPE) in total hip arthroplasty (THA), orthopaedic surgeons have moved towards using larger femoral heads at the cost of thinner liners to decrease the risk of instability. Several short and mid-term studies have shown minimal liner wear with the use HXLPE liners, but the safety of using thinner HXPLE liners to maximize femoral head size remains uncertain and concerns that this may lead to premature failure exist. Our objective was to analyze the outcomes for primary THA done with HXLPE liners in patients who have a 36-mm head or larger and a cup of 52-mm or smaller, with a minimum of 10-year follow-up. Additionally, linear and volumetric wear rates of the HXLPE were evaluated in those with a minimum of seven-year follow-up. We hypothesized that there would be minimal wear and good clinical outcome. Between 2000 and 2010, we retrospectively identified 55 patients that underwent a primary THA performed in a high-volume single tertiary referral center using HXLPE liners with 36-mm or larger heads in cups with an outer diameter of or 52-mm or smaller. Patient characteristics, implant details including liner thickness, death, complications, and all cause revisions were recorded. Patients that had a minimum radiographic follow-up of seven years were assessed radiographically for linear and volumetric wear. Wear was calculated using ROMAN, a validated open-source software by two independent researchers on anteroposterior X-rays of the pelvis. A total of 55 patients were identified and included, with a mean age of 74.8 (range 38.67 - 95.9) years and a mean BMI of 28.98 (range 18.87 - 63-68). Fifty-one (94.4%) of patients were female. Twenty-six (47.7%) patients died during the follow-up period. Three patients were revised, none for liner wear, fracture or dissociation. Twenty-two patients had a radiographic follow-up of minimum seven years (mean 9.9 years, min-max 7.5 –13.7) and were included in the long-term radiographic analysis. Liner thickness was 5.5 mm at 45 degrees in all cases but one, who had a liner thickness of 4.7mm, and all patients had a cobalt-chrome head. Cup sizes were 52mm (n=15, 68%) and 50mm (n=7, 32%). Mean linear liner wear was 0.0470 mm/year (range 0 - 0.2628 mm) and mean volumetric wear was 127.69 mm3/year (range 0 - 721.23 mm3/year). Using HXLPE liners with 36-mm heads or bigger in 52-mm cups or smaller is safe, with low rates of linear and volumetric wear in the mid to long-term follow-up. Patients did not require revision surgery for liner complications, including liner fracture, dissociation, or wear. Our results suggest that the advantages of using larger heads should outweigh the potential risks of using thin HXLPE liners

Aims. Femoral stems with exchangeable (modular) necks were introduced to offer surgeons an increased choice when determining the version, offset and length of the femoral neck during total hip arthroplasty (THA). It was hoped that this would improve outcomes and reduce complications, particularly dislocation. In 2010, the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) first reported an increased rate of revision after primary THA using femoral stems with an exchangeable neck. The aim of this study was to provide a more comprehensive up-to-date analysis of primary THA using femoral stems with exchangeable and fixed necks. Materials and Methods. The data included all primary THA procedures performed for osteoarthritis (OA), reported to the AOANJRR between 01 September 1999 and 31 December 2014. There were 9289 femoral stems with an exchangeable neck and 253 165 femoral stems with a fixed neck. The characteristics of the patients and prostheses including the bearing surface and stem/neck metal combinations were examined using Cox proportional hazard ratios (HRs) and Kaplan-Meier estimates of survivorship. . Results. It was found that prostheses with an exchangeable neck had a higher rate of revision and this was evident regardless of the bearing surface or the size of the femoral head. Exchangeable neck prostheses with a titanium stem and a cobalt-chromium neck had a significantly higher rate of revision compared with titanium stem/titanium neck combinations (HR 1.83, 95% confidence interval 1.49 to 2.23, p < 0.001). Revisions were higher for these combinations compared with femoral stems with a fixed neck. Conclusion . There appears to be little evidence to support the continued use of prostheses with an exchangeable neck in primary THA undertaken for OA. Cite this article: Bone Joint J 2017;99-B:766–73

Aim. To study whether revision for prosthetic joint infection (PJI) after early PJI in primary Total Hip Arthroplasty (THA) is associated with a high mortality, when compared with:. Patients, who did not undergo revision for any reason and Patients who underwent an aseptic revision. Method. This population-based cohort study was based on the Danish Hip Arthroplasty Register on primary THA performed in Denmark from 2005 to 2014. Data from the Danish Hip Arthroplasty Register were linked to microbiology databases, the National Register of Patients, and the Civil Registration System to obtain data on microbiology, comorbidity, and vital status on all patients. The mortality risk for the patients who underwent revision for PJI within 1 year from implantation of primary THA was compared with (1) the mortality risk for patients who did not undergo revision for any reason within 1 year of primary THA; and (2) the mortality risk for patients who underwent an aseptic revision. Results. A total of 68,504 primary THAs in 59,954 patients were identified, of those 445 primary THAs underwent revision for PJI, 1350 primary THAs underwent revision for other causes and the remaining 66,709 primary THAs did not undergo revision. Patients were followed from implantation of primary THA until death or 1 year of follow-up, or, in case of a revision, 1 year from the date of revision. Within 1 year of primary THA, 8% (95% CI, 6%–11%) of patients who underwent revision for PJI died. The adjusted relative mortality risk for patients with revision for PJI was 2.18 (95% CI, 1.54–3.08) compared with the patients who did not undergo revision for any cause (p < 0.001). The adjusted relative mortality risk for patients with revisions for PJI compared with patients with aseptic revision was 1.87 (9f5% CI, 1.11–3.15; p = 0.019). Patients with enterococci-infected THA had a 3.10 (95% CI, 1.66–5.81) higher mortality risk than patients infected with other bacteria (p < 0.001). Conclusions. Revision for PJI within 1 year after primary THA induces an increased mortality risk during the first year after the revision surgery. Especially enterococci-infected THA have a high motrtaly risk

Background. Uncemented dual-tapered stems are a popular choice for primary total hip arthroplasty (THA). The purpose of this study was to examine long-term outcomes after primary THA utilizing a single dual-tapered stem. Patients and Methods. Utilizing our total joint registry, we retrospectively identified 1215 THAs (1055 patients) performed with an uncemented dual-tapered stem from 1998 to 2009. Mean age was 55 years, 70% were male, and mean BMI was 30 kg/m. 2. Mean follow-up was 10 years. Analysis included implant survivorship, clinical outcomes, and radiographic results. Results. Survivorship from stem revision for any reason was 99.0% at 5 years postoperatively and 98.4% at both 10 and 15 years. Survivorship from stem revision for aseptic loosening was 99.9% at 5-, 10-, and 15-years postoperatively. Survivorship from stem revision for periprosthetic fracture was 99.7%, 99.1%, and 98.9% at 5, 10, and 15 years postoperatively, respectively. In total, 18 (1.5%) stems underwent revision. Revisions were performed for periprosthetic fracture (10, 0.82%), infection (7, 0.58%), and aseptic loosening (1, 0.08%). Intraoperative fracture occurred in 58 (4.77%) THAs treated with cerclage wiring (52, 89.66%) or no treatment (6, 10.34%) and insertion of a standard prosthesis. At mean radiographic follow-up of 10 years, only 4 of 1084 (0.37%) stems with 1-year radiographic follow-up had any radiolucency around the proximal ongrowth coating, and only 1 (0.10%) of these had a circumferential radiolucent line (Gruen zones 1–14). Conclusions. This uncemented dual-tapered femoral stem is associated with excellent survivorship, reasonably low intraoperative fracture rate, and extremely low rates of revision for aseptic loosening, periprosthetic fracture, and infection when used for primary THA at long-term follow up. For any tables or figures, please contact the authors directly

Aims. Concurrent hip and spine pathologies can alter the biomechanics of spinopelvic mobility in primary total hip arthroplasty (THA). This study examines how differences in pelvic orientation of patients with spine fusions can increase the risk of dislocation risk after THA. Patients and Methods. We identified 84 patients (97 THAs) between 1998 and 2015 who had undergone spinal fusion prior to primary THA. Patients were stratified into three groups depending on the length of lumbar fusion and whether or not the sacrum was involved. Mean age was 71 years (40 to 87) and 54 patients (56%) were female. The mean body mass index (BMI) was 30 kg/m. 2. (19 to 45). Mean follow-up was six years (2 to 17). Patients were 1:2 matched to patients with primary THAs without spine fusion. Hazard ratios (HR) were calculated. Results. Dislocation in the fusion group was 5.2% at one year versus 1.7% in controls but this did not reach statistical significance (HR 1.9; p = 0.33). Compared with controls, there was no significant difference in rate of dislocation in patients without a sacral fusion. When the sacrum was involved, the rate of dislocation was significantly higher than in controls (HR 4.5; p = 0.03), with a trend to more dislocations in longer lumbosacral fusions. Patient demographics and surgical characteristics of THA (i.e. surgical approach and femoral head diameter) did not significantly impact risk of dislocation (p > 0.05). Significant radiological differences were measured in mean anterior pelvic tilt between the one-level lumbar fusion group (22°), the multiple-level fusion group (27°), and the sacral fusion group (32°; p < 0.01). Ten-year survival was 93% in the fusion group and 95% in controls (HR 1.2; p = 0.8). Conclusion. Lumbosacral spinal fusions prior to THA increase the risk of dislocation within the first six months. Fusions involving the sacrum with multiple levels of lumbar involvement notably increased the risk of postoperative dislocation compared with a control group and other lumbar fusions. Surgeons should take care with component positioning and may consider higher stability implants in this high-risk cohort

Introduction. Patients undergoing primary total hip arthroplasty (THA) with prior lumbar spine fusion (LSF) are at high risk for instability with reported incidence of dislocation as high as 8.3%. The use of dual mobility cups in patients undergoing revision THA, another high risk group, has demonstrated decreased incidence of instability. Purpose of this study was to evaluate the risk of instability in patients undergoing primary THA with a history of prior LSF using dual mobility cups. Methods. This was a multi-center retrospective study with 93 patients undergoing primary THA using a dual mobility cup with prior history of instrumented LSF. The primary outcome investigated was instability. Secondary variables investigated included number of levels fused, approach, length of stay, and other complications. The minimum follow-up time was 1 year since the majority of dislocations occur during first year following the primary THA. Results. There were 56 females and 47 males with average age of 66 years (46–87) and average BMI of 30. Mean follow up was 31 months (range 12 – 124.2). Surgical approach included: posterior (63), direct lateral (15), anterior (11), direct superior (4). 44% had one level fusion, 29% with 2 levels, and 15% with 3 or more levels fused. There were no dislocations or infections in this study group. There was one intraoperative fracture and one DVT. Conclusions. Patients undergoing primary THA with prior LSF are a high risk group with an increased risk for instability due to the loss of normal spino-pelvic relationship. The use of dual mobility cups in a high risk group of patients in this study demonstrated excellent results with no incidence of dislocation. Despite the limitations in this study with varying approaches and multiple sites, the use of dual mobility cups to decrease the incidence of instability in patients with prior LSF appears promising. For any tables or figures, please contact the authors directly

The aim of this study is the comparative assessment of long term clinical (subjective and objective), functional and quality of life outcome data between primary and revision THA. 122 patients (130 hips) who underwent cementless revision THA of both components (TMT cup, Wagner SL stem, Zimmer Biomet) for aseptic loosening only (Group A) were compared to a matched group of 100 patients (100 hips) who underwent cementless primary THA for osteoarthritis (Synergy stem, R3 cup, Smith & Nephew) (Group B). Outcomes were evaluated with survival analysis curves, Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford hip score (OHS), Short form-12 health survey (SF-12) and EQ-5D-5L scales. Mobility was assessed with walking speed, timed up and go test (TUG), Parker mobility, Lower extremity function score (LEFS) and UCLA scores. At a mean follow up of 14.4 years (10 to 20) a cumulative success rate of 96% (95% CI 96 to 99%) in Group A and 98% (95% CI 97 to 99%) in Group B with operation for any reason as an end point was recorded. Statistically significant differences between groups were developed for WOMAC (Mann-Whitney U test, p= 0.014), OHS (Mann-Whitney U test, p= 0.020) and physical component of SF-12 scores (Mann-Whitney U test, p= 0.029) only. In Group A, in multiple regression analysis, patients’ cognition (p=0.001), BMI (p=0.007) and pain (p=0.022) were found to be independent factors influencing functional recovery (WOMAC). Similarly, pain (p=0.03) was found to influence quality of life (EQ-5D-5). In the long term, revision THA shows satisfactory but inferior clinical, functional, and quality of life outcomes when compared to primary THA. Residual pain, BMI and cognitive impairment independently affect functional outcomes

Background. The impact of a patient's activity level following total hip arthroplasty (THA) remains controversial, with some concerned about increased polyethylene wear, aseptic loosening and revisions. The purpose of this study is to report on implant survivorship and outcomes of high activity patients compared to low activity patients after THA with current polyethylene. Methods. A retrospective review identified 2002 patients (2532 hip) that underwent a primary THA with vitamin E infused highly crosslinked polyethylene liner and 2-year minimum follow-up or revision. Patients were divided in two groups based on their University of California Los Angeles (UCLA) activity level: Low activity (LA) (UCLA ≤5) and high activity (HA) (UCLA ≥ 6). Outcomes included Harris Hip Score, UCLA activity score, complications and reoperations. Multivariate nominal regression analysis was performed to evaluate the significance of postoperative activity level on survivorship while controlling for age, gender, preoperative pain, HHS and body mass index (BMI). Results. Mean follow-up was 4.5 years (range, 0.3 to 9.9 years). The LA group had significantly more female patients, were older, higher BMI and lower HHS pre-operatively (all with p<0.001). HA group had significantly higher improvements in HHS (p<0.001) and UCLA activity score (p<0.001). Aseptic revisions were performed in 2.1% of the LA group and in 0.4% hips of the HA group (p<0.001). Multivariate regression analysis found that a higher postoperative activity level remained a significant factor for improved aseptic survivorship with an OR of 4.9 (95% CI, 1.1 to 21.2, p=0.03). The aseptic 5-year survivorship was 99.6% for the HA group and 98% for the LA group (p<0.001). Conclusions. Higher activity level after primary THA did not increase the risk for midterm aseptic or all cause failure. Patient activity level after THA may not need to be limited with modern polyethylene

Aims. Several short- and mid-term studies have shown minimal liner wear of highly cross-linked polyethylene (HXLPE) in total hip arthroplasty (THA), but the safety of using thinner HXLPE liners to maximize femoral head size remains uncertain. The objective of this study was to analyze clinical survival and radiological wear rates of patients with HXLPE liners, a 36 mm femoral head, and a small acetabular component with a minimum of ten years’ follow-up. Methods. We retrospectively identified 55 patients who underwent primary THA performed at a single centre, using HXLPE liners with 36 mm cobalt-chrome heads in acetabular components with an outer diameter of 52 mm or smaller. Patient demographic details, implant details, death, and all-cause revisions were recorded. Cox regression and Kaplan-Meier survival was used to determine all-cause and liner-specific revision. Of these 55 patients, 22 had a minimum radiological follow-up of seven years and were assessed radiologically for linear and volumetric wear. Results. Overall survival rate for all-cause revision was 94.5% (95% confidence interval (CI) 81.7% to 97.2%) at a mean follow-up of 12.8 years (10.9 to 18.7). Three patients were revised, none for liner wear, fracture, or dissociation. A total of 22 patients were included in the radiological analysis (mean follow-up 9.9 years (7.5 to 13.7)). Mean linear liner wear was 0.085 mm (95% CI -0.086 to 0.257) and the volumetric wear rate was 11.097 mm. 3. /year (95% CI -6.5 to 28.7). Conclusion. Using HXLPE liners with 36 mm heads in 52 mm acetabular components or smaller is safe, with excellent survival and low rates of linear and volumetric wear at medium-term follow-up. Patients did not require revision surgery for liner complications such as fracture, dissociation, or wear. Our results suggest that the advantages of using larger heads outweigh the potential risks of using thin HXLPE liners. Cite this article: Bone Joint J 2023;105-B(1):29–34

Introduction. Registry data from around the world demonstrates instability following primary THA is a leading indication for revision. However, the burden of THA dislocation is poorly documented and is not routinely recorded or reported at a national level. Our aim was to determine the rate of dislocation following primary THA in contemporary practice and in doing so determining the burden of THA dislocation to the NHS in Wales. Method. We considered all Welsh residents who underwent primary THA from 2011–2016. Via clinical coding linkage using Patient Episode Database for Wales (PEDW), the equivalent of HES data in England, we were able determine re-admission for dislocation, revision THA following dislocation and all cause revision at 1 to 5 years follow-up. Results. In a cohort of 20,816 primary THA the dislocation rate at 1-year follow-up was 1.1% (95%CI 0.97–1.25). This increased incrementally to 2.2% (95%CI 1.78–2.72) at 5 years. At 1 year the overall revision rate was 1.3% of which 0.3% was following instability. The median time to dislocation was 46 days and 67.8% of first time dislocations occurred within 6 months of index surgery. We undertook a clinical coding data validation for a sub-group of 2,677 THA procedures, cross-referencing hospital records and theatre logbooks with PEDW data and demonstrated a correlation of 90.6% (95%CI 75.8–96.8). We observed 229 first time dislocation events, but during the total study period there were 1179 emergency admissions for dislocated THA with a mean hospital length of stay of 5.5 days. Discussion & Conclusions. This study provides benchmarking data at a national level regarding the risk of dislocation for patients undergoing primary THA. Importantly it demonstrates the significant accumulative burden of dislocation following THA for both patients and impact on NHS resources

Aims. The purpose of this study is to evaluate early outcomes with the use of a smartphone-based exercise and educational care management system after total hip arthroplasty (THA) and demonstrate decreased use of in-person physiotherapy (PT). Methods. A multicentre, prospective randomized controlled trial was conducted to evaluate a smartphone-based care platform for primary THA. Patients randomized to the control group (198) received the institution’s standard of care. Those randomized to the treatment group (167) were provided with a smartwatch and smartphone application. PT use, THA complications, readmissions, emergency department/urgent care visits, and physician office visits were evaluated. Outcome scores include the Hip disability and Osteoarthritis Outcome Score (HOOS, JR), health-related quality-of-life EuroQol five-dimension five-level score (EQ-5D-5L), single leg stance (SLS) test, and the Timed Up and Go (TUG) test. Results. The control group was significantly younger by a mean 3.0 years (SD 9.8 for control, 10.4 for treatment group; p = 0.007), but there were no significant differences between groups in BMI, sex, or preoperative diagnosis. Postoperative PT use was significantly lower in the treatment group (34%) than in the control group (55.4%; p = 0.001). There were no statistically significant differences in complications, readmissions, or outpatient visits. The 90-day outcomes showed no significant differences in mean hip flexion between controls (101° (SD 10.8)) and treatment (100° (SD 11.3); p = 0.507) groups. The HOOS, JR scores were not significantly different between control group (73 points (SD 13.8)) and treatment group (73.6 points (SD 13); p = 0.660). Mean 30-day SLS time was 22.9 seconds (SD 19.8) in the control group and 20.7 seconds (SD 19.5) in the treatment group (p = 0.342). Mean TUG time was 11.8 seconds (SD 5.1) for the control group and 11.9 (SD 5) seconds for the treatment group (p = 0.859). Conclusion. The use of the smartphone care management system demonstrated similar early outcomes to those achieved using traditional care models, along with a significant decrease in PT use. Noninferiority was demonstrated with regard to complications, readmissions, and ED and urgent care visits. This technology allows patients to rehabilitate on a more flexible schedule and avoid unnecessary healthcare visits, as well as potentially reducing overall healthcare costs. Cite this article: Bone Joint J 2021;103-B(7 Supple B):91–97

Introduction. The results of repair and reconstruction of lesions found in the abductor muscles and tendons during posterior approach to primary total hip arthroplasty (THA) were reported in 2018. During the course of this series it became apparent that the extent of damage in the abductor tendons and muscles usually was obscured by the hypertrophic greater trochanteric bursa, especially the deep layer adherent to the greater trochanter and abductor muscles. The purpose of this study was to evaluate the surgeon's ability to see these lesions during standard posterior approach, and also to describe the dissection necessary to fully expose them. Patients and Methods. A total of 525 patients (525 hips) underwent primary THA through posterior approach between 2009 and 2013. Fifty-four patients had mild chronic damage to the tendon. Forty-one patients had severe damage with major avulsion of the gluteus medius and minimus muscles. Results. None of the hips with normal abductor muscle structure had a dense trochanteric bursa to obscure the abductor attachment to bone, but in 35 hips (85.3%) with significant abductor tendon avulsion, the lesions in the tendons were hidden from view until the greater trochanteric bursa was dissected. Splitting the deep layer of the trochanteric bursa in line with the fibers of the abductor muscles was necessary to reveal avulsion of the tendons from the edge of the greater trochanter. Only six hips (14.6%) had abductor tendon avulsion from the greater trochanter that could be seen without removing the trochanteric bursa tissue. Conclusion. The posterior approach offered excellent exposure of the abductor mechanism during primary THA, but the avulsion defects in the gluteus medius and minimus muscles remained obscured until the outer layer of the greater trochanteric bursa was completely removed and the deep fibrous layer was dissected adequately to expose the tendon attachment to bone. For any tables or figures, please contact the authors directly

Aims. Only a small number of studies exist that report the results of EBM-produced porous coated trabecular titanium cups in primary total hip arthroplasty (THA). This study aims to investigate the patient satisfaction level, clinical function and radiographic outcomes of the patients who underwent THA using an EBM-produced porous coated titanium cup. Patients and Methods. A total of 32 patients who underwent primary THA with using an EBM-produced porous coated titanium cup from five hospitals between May and December, 2012 were retrospectively reviewed. Five patients were lost prior to the minimum 6-year follow-up. Clinical and radiographic outcomes were analyzed with an average follow-up of 81.48 (range: 77.00–87.00) months. Results. The median HHS and SF-36 scores improved significantly while the WOMAC Osteoarthritis Index decreased significantly at the latest follow-up (p<0.001). Eighteen (66.7%) patients rated their satisfaction level as very satisfied, 6 (22.2%) as satisfied, 2 (7.4%) as neutral and 1(3.7%) as dissatisfied. No intraoperative or postoperative complications were identified, including aseptic cup loosening, hip dislocation, periprosthetic joint infection, periprosthetic fracture, nerve palsy, hematoma. At the latest follow-up, all cups were considered to have achieved fixation via bone ingrowth with three or more of the five signs occurring in the most recent X-ray. However, three cups revealed radiolucent lines with a width of less than 1 mm. These radiolucent lines were distributed in the DeLee-Charnley zone 1 in 1 patient, zone 3 in another patient and the area between zone1 and zone 2 in an additional patient. The latest postoperative centers of rotation were restored nearly to the anatomic center of rotation both vertically and horizontally and the acetabular cups obtained satisfactory orientation postoperatively. Conclusions. The mid-term follow-up of patients who underwent primary THA using EBM-produced porous coated titanium cups demonstrated favorable patient satisfaction, clinical function and adequate biological fixation. For any figures or tables, please contact authors directly

Aims. The aim of this study was to estimate the 90-day risk of revision for periprosthetic femoral fracture associated with design features of cementless femoral stems, and to investigate the effect of a collar on this risk using a biomechanical in vitro model. Materials and Methods. A total of 337 647 primary total hip arthroplasties (THAs) from the United Kingdom National Joint Registry (NJR) were included in a multivariable survival and regression analysis to identify the adjusted hazard of revision for periprosthetic fracture following primary THA using a cementless stem. The effect of a collar in cementless THA on this risk was evaluated in an in vitro model using paired fresh frozen cadaveric femora. Results. The prevalence of early revision for periprosthetic fracture was 0.34% (1180/337 647) and 44.0% (520/1180) occurred within 90 days of surgery. Implant risk factors included: collarless stem, non-grit-blasted finish, and triple-tapered design. In the in vitro model, a medial calcar collar consistently improved the stability and resistance to fracture. Conclusion. Analysis of features of stem design in registry data is a useful method of identifying implant characteristics that affect the risk of early periprosthetic fracture around a cementless femoral stem. A collar on the calcar reduced the risk of an early periprosthetic fracture and this was confirmed by biomechanical testing. This approach may be useful in the analysis of other uncommon modes of failure after THA. Cite this article: Bone Joint J 2019;101-B:779–786

Background. Over 35% of surgeons in the United States, and 10% in Canada use the direct anterior approach for primary total hip arthroplasty (THA). Some of the key barriers in its wider adoption are the learning curve and associated increased risk of adverse events. The purpose of this study was to determine the adoption rate as well as 90-day re-admission and adverse event of the anterior approach in a community-based hospital. Methods. From December 2015 to August 2018, two laterally based approach senior orthopaedic surgeons with over 20 years of practice performed 319 primary total hip replacements, with 164 being done through the anterior approach and 155 through the lateral approach. All but 8 of the anterior approaches were done on a regular operating table. Results. The anterior and lateral approach groups were comparable in age with mean 69.1+/− 10.2 and 68.9+/−9.3, respectively (p= 0.886), however the anterior group had patients with a statistically significantly lower BMI than the lateral group with mean 28.2+/−5.4 and 31.0+/−6.3, respectively (p < 0.001). Furthermore, there was a much lower percentage of females in the anterior group than in the lateral group with 49.4% and 65.2%, respectively (p= 0.004). It took surgeon A and B 12 and 24 months for the anterior approach to represent over 50% of their monthly cases, respectively. The anterior approach now accounts for approximately 80% of surgeon A's practice and 100% in surgeon B's practice in the last 6 and 18 months, respectively. Intraoperative adverse events were comparable between anterior and lateral approaches, with one incidence in each group (p= 0.968), however post-operative adverse events were more prevalent in the lateral group (n= 24) when compared to anterior group (n= 11) (p= 0.012). Further details of both approaches are provided in figure 1. Conclusion. Within a well-structured environment, the anterior approach can be safely introduced into a community-based practice. The progressive adoption of a new surgical technique combined with more experienced surgeon as a resource is an effective way that requires further study. For any figures or tables, please contact the authors directly

Background. The purpose of this study is to evaluate the early outcomes with the use of a smartphone-based exercise and educational platform after primary total hip arthroplasty compared to a standard of care control group. Methods. A multicenter prospective randomized control trial was conducted evaluating the use of the mymobility smartphone-based care platform for primary total hip arthroplasty (THA). Patients randomized to the control group (198 patients) received the respective institution's standard of care. Those randomized to mymobility treatment group (167 patients) were provided an Apple Watch and mymobility smartphone application. The application provides pre and postoperative educational content, video directed exercise programs as well as tracks the patient's activity. Patients in the treatment group were not initially prescribed physical therapy, but could be if their surgeon deemed it necessary. Early outcomes assessed included 90-day hip range of motion, HOOS JR scores, 30-day single leg stance (SLS) and time up and go (TUG) test. We also evaluated PT utilization, THA complications associated with readmissions, ER visits not associated with readmissions, urgent care (non standard of care) visits, and physician office visits. Outcome scores include HOOS-Jr, EQ-5D-5L, single stance (SLS), Timed up and go (TUG). Satisfaction scores for the procedure and the mymobility study group were also recorded. Results. The control group was significantly younger by 3.0 years (p=0.007), but no significant difference between groups in BMI, gender or preoperative diagnosis. Postoperative PT utilization was statistically lower in the mymobility group. (P=.001). There were no statistically significant differences in complications, readmissions, or office visits. The 90-day outcomes showed no significant differences in hip flexion between controls (101.3±10.9) and mymobility (99.8 ±12) (p=0.34). HOOS JR scores were not significantly different between control group (84 ±14.5) and mymobility group (81 ±13) (p=0.15). Mean 30-day SLS time was 22.5 ±20 sec in the control group and 19.8 ±19 sec in the mymobility group (p=0.25). Mean TUG time was 14.1 ±27.4 sec for control group and 16.1 ±43.3 sec for my mobility group (p=0.7). Conclusion. The use of the mymobility care platform demonstrated similar early outcomes to traditional care models. This study showed a significant decrease in PTA utilization. Initial findings demonstrated non inferiority of the mymobility platform with regards to complications, readmissions, emergency room and urgent care visits. Strengths of this study include randomized, multicentered study design. Both groups were balanced except for age. Weakness of this study is the lack of preoperative functional testing which may influence postoperative single stance. This technology allows patients to rehabilitate on a more flexible schedule, avoid unnecessary healthcare visits as well as potentially decrease overall healthcare costs

Total hip arthroplasty has been constantly evolving with technological improvements to achieve the best survival rates. Although the new implants are under closer surveillance through processes such as Beyond Compliance, orthopaedic surgeons generally tend to look out for the latest implants with good short-term results and hope for better long-term results for these. We questioned whether such an assumption or bias is valid. We analysed the data of Kaplan-Meier estimates of cumulative revisions of primary hip replacement by fixation, stem/cup brand and bearing combinations from the NJR 19th Annual Report published in September 2022. We performed a univariate linear regression analysis to predict the 10- and 15-year revision rates for these different hip implant combinations from the 3- and 5-year revision rates. Thirty-seven implant combinations had their 15-year revision rates reported and 67 had the 10-year revision rates. The correlation co-efficients were 0.43 and 0.58 for the 3-year and 5-year revision rates against 15-year revision rates. Only 17% of the variance in 15-year revision rates could be predicted by a linear regression model from the 3-year revision rate and 32% from the 5-year revision rate. Corresponding values for the 10-year revision rates were 46% and 67%. 95% prediction intervals for the 15-year revision rate were +/− 3.1% from the 3-year revision rate and +/− 2.8% from the 5-year revision rate. Corresponding values for the 10-year revision rates were +/− 1.3% and +/− 1%. 19 of 37 implant combinations showed 15-year revision rate of more than 4%. Average 3-year and 5-year revision rates for this cohort was 1.0% and 1.42% compared to 1.4% and 1.9% for the rest and the difference was statistically significant. Although average early revision rates showed small but significant difference between the groups with lower and higher 15-year revision rates, the prediction intervals for 15-year revision rates for individual hips based on their 3-year and 5-year revision rates are very wide. Three- and 5-year revision rates for primary total hip replacements are poor predictors of 15-year revision rates

Introduction. Previous registry studies of ceramic-on-polyethylene (C-PE) and ceramic-on-ceramic (COC) have focused on revision outcomes following primary surgery. Less is known about the effect of ceramic bearings on infection, dislocation, and mortality as outcomes following primary total hip arthroplasty (THA) for the Medicare population. We asked (1) does the use of C-PE bearings influence outcomes following THA as compared with metal-on-polyethylene (M-PE); and (2) does the use of COC bearings influence outcomes following THA as compared with M-PE?. Methods. A total of 315,784 elderly Medicare patients (65+) who underwent primary THA between 2005 and 2014 with known bearing types were identified from the Medicare 100% inpatient sample administrative database. Outcomes of interest included relative risk of 90-day readmission, infection, dislocation, revision, or mortality at any time point after primary surgery. Propensity scores were developed to adjust for selection bias in the choice of bearing type at index primary surgery. Cox regression incorporating propensity score stratification (10 levels) was then used to evaluate the impact of bearing surface selection on outcomes, after adjusting for patient-, hospital-, and surgeon-related factors. Results. For primary THA patients treated with C-PE bearings and COC bearings, there was significantly reduced risk of infection relative to M-PE bearings (C-PE Hazard Ratio, HR: 0.86, p=0.001; COC Hazard Ratio, HR: 0.74, p=0.01). For the C-PE cohort, we also observed reduced risk of 90-day readmission (HR: 0.94, p<0.001); dislocation (HR: 0.81, p<0.001); and mortality (HR: 0.92, p<0.001). There was no significant difference in risk of revision for either the C-PE or COC bearing cohorts when compared with M-PE. For the COC cohort, there was no significant difference in readmission, dislocation, or mortality risk. Conclusions. The results indicate that, after adjusting for selection bias and various confounding patient-, surgeon-, and hospital-related factors, Medicare patients treated with primary THA with ceramic bearings exhibit lower risk of infection than those treated with M-PE bearings. In addition, C-PE bearings were associated with lower risk of dislocation and mortality. As in previous registry studies, we found that ceramic bearings have similar revision risk as M-PE bearings in primary THA at between 8 and 9 years of follow-up. The findings of this study support further research into the long-term association between ceramic bearings in primary THA and clinical outcomes

Introduction. There is renewed interest in dislocation after surgical approach with popularization of the direct anterior approach. The purported advantage of both the lateral and direct anterior approaches is decreased risk of dislocation. The purpose of this study was to assess the risk of dislocation by approach following modern primary THA. Methods. All primary THAs at a single academic institution from 2010 to 2017 were analyzed through our institutional total joint registry. There were 7023 THAs including 3754 posterior, 1732 lateral, and 1537 direct anterior. Risk of dislocation was assessed against the competing risks of revision surgery and death as well as by individual patient and surgical factors including surgical approach. Risk of revision surgery was considered as a secondary outcome. Step-wise selection was utilized to develop multivariable models. Clinical outcomes were documented with the Harris Hip Score (HHS). Mean age was 63 years, 51% were female, and mean body mass index (BMI) was 30 kg/m. 2. Minimum follow-up was 2 years. Results. The cumulative incidence of dislocation at 1-year and 5-years by approach was as follows: posterior (2.1%; 3.0%), lateral (0.7%; 0.7%), direct anterior (0.4%; 0.4%) (p<0.001) (Figure 1). Compared to the posterior cohort, the adjusted risk of dislocation was decreased for the lateral (hazard ratio [HR]=0.28, p<0.001) and direct anterior cohorts (HR=0.18, p<0.001). The cumulative incidence of revision for instability at 1-year and 5-years by approach was as follows: posterior (0.8%; 1.0%), lateral (0.6%; 0.6%), direct anterior (0%; 0%) (p=0.09). The adjusted risk of all-cause revision surgery was increased among the lateral cohort compared to posterior (HR=1.75, p=0.003) and direct anterior (HR=2.44, p=0.002) and among patients with diagnoses other than osteoarthritis (HR=2.89, p<0.001). Among patients who dislocated, 69 (83%) had anteversion >25° (Figure 2). Mean increase in HHS from preoperative assessment to final follow-up was greatest among direct anterior patients (37 points), followed by posterior patients (33 points), followed by lateral patients (29 points) (p<0.05, all comparisons). Conclusions. This study documents the risk of dislocation by surgical approach among a large contemporary cohort undergoing primary THA. The risk of dislocation was higher following the posterior approach, whereas all-cause revision surgery was found to be higher following the lateral approach. For any tables or figures, please contact the authors directly

Despite the widespread success of total hip arthroplasty (THA), postoperative pain management remains a concern. Opioids have classically been administered for pain relief after THA, but their side effect profile, in addition to the cognizance of the growing opioid epidemic, has incited a shift toward alternative pain modalities. Although the nonsteroidal anti-inflammatory drug (NSAID) diclofenac is a promising addition, its impact on immediate THA outcomes has not previously been investigated. Thus, in the present study, we evaluate the effects of adjunctive diclofenac on: 1) postoperative pain intensity, 2) opioid consumption, 3) discharge destination, 4) length of stay, and 5) patient satisfaction in primary THA patients. A retrospective review was performed to identify all patients who underwent primary THA by a single surgeon between May 1 and September 31, 2017. Patients were stratified into a study group (n=25), who were treated with postoperative diclofenac in addition to the standard pain control regimen, and a control group (n=88), who did not receive adjunctive diclofenac. Repeated-measures analysis of variance (ANOVA)/analysis of covariance (ANCOVA) and chi-square/logistic regression analysis were used for continuous and categorical variables, respectively. Patients receiving adjunctive diclofenac were more likely to be discharged home than to inpatient facilities (O.R. 4.02, p=0.049). In addition, patient satisfaction with respect to how well and how often pain was controlled (p= 0.0436 and p=0.0217, respectively) was significantly greater in the diclofenac group. Finally, patients who received diclofenac had lower opioid consumption on postoperative days one and two (−67.2 and −129 mg, respectively, p=0.001 for both). The rapid growth of THA as an outpatient procedure has intensified the urgency of improving postoperative pain management. The present study demonstrates that THA patients receiving adjunctive diclofenac were more likely to be discharged home, had reduced opioid consumption, and experienced greater satisfaction. This will, in turn, decrease complications and total hospital costs, leading to a more cost-effective pain control regimen. In order to further investigate the optimal regimen, future studies comprising larger cohort, as well as a comparison of diclofenac to other NSAIDs, are warranted

Aims. We compared implant and patient survival following intraoperative periprosthetic femoral fractures (IOPFFs) during primary total hip arthroplasty (THA) with matched controls. Patients and Methods. This retrospective cohort study compared 4831 hips with IOPFF and 48 154 propensity score matched primary THAs without IOPFF implanted between 2004 and 2016, which had been recorded on a national joint registry. Implant and patient survival rates were compared between groups using Cox regression. Results. Ten-year stem survival was worse in the IOPFF group (p < 0.001). Risk of revision for aseptic loosening increased 7.2-fold following shaft fracture and almost 2.8-fold after trochanteric fracture (p < 0.001). Risk of periprosthetic fracture of the femur revision increased 4.3-fold following calcar-crack and 3.6-fold after trochanteric fracture (p < 0.01). Risk of instability revision was 3.6-fold after trochanteric fracture and 2.4-fold after calcar crack (p < 0.001). Risk of 90-day mortality following IOPFF without revision was 1.7-fold and 4.0-fold after IOPFF with early revision surgery versus uncomplicated THA (p < 0.001). Conclusion. IOPFF increases risk of stem revision and mortality up to ten years following surgery. The risk of revision depends on IOPFF subtype and mortality risk increases with subsequent revision surgery. Surgeons should carefully diagnose and treat IOPFF to minimize fracture progression and implant failure. Cite this article: Bone Joint J 2019;101-B:1199–1208

Modular femoral stems offer surgeons great flexibility in biomechanical configuration during total hip replacement (THR) however introduce a taper-trunnion articulation known to be a source of additional wear debris through crevice, fretting and galvanic corrosion with mixed material combinations. This study aimed to investigate the influence of the trunnion bearing surface combination on the revision rate following primary total hip replacement (THR). All patients who underwent THR using an Exeter V40 cemented stainless steel stem and monobloc cemented polyethylene acetabular component (uncemented cups excluded to standardise the acetabular bearing surface and fixation) between January 2003 and December 2019 were extracted from the National Joint Registry for England, Wales, Northern Ireland, and the Isle of Man. The primary exposure was the head substrate used corresponding to the trunnion bearing. Time-to-event was determined by duration of implantation from primary surgery to revision with cases censored at death or end of available follow-up. Multivariable Cox proportional hazard models were used to identify predictors of all cause revision, adjusted for age, sex, American Association of Anaesthesiologists (ASA) grade, body mass index, surgical indication (osteoarthritis or other), and femoral head size. 229,870 THR were identified (66% female, mean age 73.4 years (SD 9.1) with the majority (91%) performed for osteoarthritis of which 4,598 were revised. Mean time from primary to revision or censoring was 6.8 years (SD 4.0). Multivariable modelling showed CoCr/SS trunnions were associated with a significantly higher risk of revision (hazard ratio (HR) 1.31 (95%CI 1.15 to 1.48, p<0.0001) as compared to SS/SS (reference). Both Alumina/SS (HR 0.74 (0.65 to 0.84), p<0.0001) and Zirconia/SS (HR 0.61 (0.49 to 0.74), p<0.0001) were associated with a significantly lower risk of revision. Ceramic heads on an Exeter stem were associated with significantly improved survivorship compared to metal heads in primary THR. CoCr/SS trunnion articulations had the poorest survivorship which may be contributed to by trunnionosis

We examined the association between patient-related factors and the risk of initial, short- and long-term implant failure after primary total hip replacement. We used data from the Danish Hip Arthroplasty Registry between 1 January 1995 and 31 December 2002, which gave us a total of 36 984 patients. Separate analyses were carried out for three follow-up periods: 0 to 30 days, 31 days to six months (short term), and six months to 8.6 years after primary total hip replacement (long term). The outcome measure was defined as time to failure, which included re-operation with open surgery for any reason. Male gender and a high Charlson co-morbidity index score were strongly predictive for failure, irrespective of the period of follow-up. Age and diagnosis at primary total hip replacement were identified as time-dependent predictive factors of failure. During the first 30 days after primary total hip replacement, an age of 80 years or more and hip replacement undertaken as a sequela of trauma, for avascular necrosis or paediatric conditions, were associated with an increased risk of failure. However, during six months to 8.6 years after surgery, being less than 60 years old was associated with an increased risk of failure, whereas none of the diagnoses for primary total hip replacement appeared to be independent predictors