Orthopaedic Association National Joint Replacement Research Articles

THE RELATIONSHIP BETWEEN OBESITY AND THE INCIDENCE OF PRIMARY SHOULDER ARTHROPLASTY: AN AOANJRR STUDY

The aim of this study was to examine the incidence of obesity in patients undergoing primary total shoulder replacement (TSR) (stemmed and reverse) for osteoarthritis (OA) in Australia compared to the incidence of obesity in the general population.A 2017-18 cohort of 2,621 patients from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) who underwent TSR, were compared with matched controls from the Australian Bureau of Statistics (ABS) National Health Survey from the same period. The two groups were analysed according to BMI category, sex and age.According to the 2017-18 National Health Survey, 35.6% of Australian adults are overweight and 31.3% are obese. Of the primary TSR cases performed, 34.2% were overweight and 28.6% were obese. The relative risk of requiring TSR for OA increased with increasing BMI category. Class-3 obese females, aged 55-64, were 8.9 times more likely to require TSR compared to normal weight counterparts. Males in the same age and BMI category were 2.5 times more likely. Class-3 obese patients underwent TSR 4 years (female) and 7 years (male) sooner than their normal weight counterparts.Our findings suggest that the obese population is at risk for early and more frequent TSR for OA. Previous studies demonstrate that obese patients undergoing TSR also exhibit increased risks of longer operative times, higher superficial infection rates, higher periprosthetic fracture rates, significantly reduced post-operative forward flexion range and greater revision rates.Obesity significantly increases the risk of requiring TSR. To our knowledge this is the first study to publish data pertaining to age and BMI stratification of TSR Societal efforts are vital to diminish the prevalence and burden of obesity related TSR.There may well be reversible pathophysiology in the obese population to address prior to surgery (adipokines, leptin, NMDA receptor upregulation). Surgery occurs due to recalcitrant or increased pain despite non-op Mx.

THE EFFECT OF SURGEON VOLUME ON REVISION FOR DEEP PERIPROSTHETIC JOINT INFECTION: AN ANALYSIS OF 602,919 PRIMARY TOTAL KNEE ARTHROPLASTIES

Deep infection is a devastating complication of total knee arthroplasty (TKA). This study aimed to determine if there was a relationship between surgeon volume and the incidence of revision for infection after primary TKA.Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) from 1 September 1999 to 31 December 2020 for primary TKA for osteoarthritis that were revised for infection. Surgeon volume was defined by the number of primary TKA procedures performed by the surgeon in the year the primary TKA was performed and grouped as <25, 25-49, 50-74, 75-99, >100 primary TKA procedures per year. Kaplan Meir estimates for cumulative percent revision (CPR) and Cox Proportional Hazard Ratios were performed to compare rates of revision for infection by surgeon volume, with sub-analyses for patella and polyethylene use, age <65 years and male gender.5295 of 602,919 primary TKA for osteoarthritis were revised for infection. High volume surgeons (>100 TKA/year) had a significantly lower rate of revision for infection with a CPR at 1 and 17 years of 0.4% (95% CI 0.3, 0.4) and 1.5% (95% CI 1.2, 2.0), respectively, compared with 0.6% (95% CI 0.5, 0.7) and 2.1% (95% CI 1.8, 2.3), respectively, for low volume surgeons (<25 TKR/year). Differences between the high-volume group and the remaining groups remained when sub-analysis for age, gender, ASA, BMI, patella resurfacing and the use of cross-linked polyethylene (XLPE).High volume surgeons have lower rates of revision for infection in primary TKA.

EARLY PROMS FOLLOWING TOTAL HIP ARTHROPLASTY WITH AND WITHOUT COMPUTER NAVIGATION SYSTEM: A STUDY FROM THE AUSTRALIAN NATIONAL JOINT REPLACEMENT REGISTRY

Total hip arthroplasty (THA) is an effective treatment for symptomatic hip osteoarthritis (OA). While computer-navigation technologies in total knee arthroplasty show survivorship advantages and are widely used, comparable applications within THA show far lower utilisation. Using national registry data, this study compared patient reported outcome measures (PROMs) in patients who underwent THA with and without computer navigation.Data from Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) PROMs program included all primary THA procedures performed for OA up to 31 December 2020. Procedures using the Intellijoint HIP® navigation system were identified and compared to procedures using other computer navigation systems or conventional instrumentation only. Changes in PROM scores between pre-operative and 6-month post-operative time points were analysed using multiple regression model, adjusting for pre-operative score, patient age, gender, ASA score, BMI, surgical approach, and hospital type.There were 65 primary THA procedures that used the Intellijoint HIP® system, 90 procedures used other types of computer navigation, and the remaining 5,284 primary THA procedures used conventional instrumentation. The estimated mean changes in the EuroQol visual analogue scale (EQ VAS) score and Oxford Hip score did not differ significantly when Intellijoint® was compared to conventional instruments (estimated differences of 2.4, 95% CI [-1.7, 6.5], p = 0.245, and −0.5, 95% CI [-2.5, 1.4], p = 0.592, respectively). The proportion of patients who were satisfied with their procedure was also similar when Intellijoint® was compared to conventional instruments (rate ratio 1.06, 95% CI [0.97, 1.16], p = 0.227).The preliminary data demonstrate no significant difference in PROMs when comparing the Intellijoint HIP® THA navigation system with both other navigation systems and conventional instrumentation for primary THAs performed for OA. Level of evidence: III (National registry analysis)

TRENDS IN THE SURGICAL MANAGEMENT OF PROXIMAL HUMERUS FRACTURE OVER THE LAST 20 YEARS

Proximal humerus fractures (PHF) are common, accounting for approximately 5% of all fractures. Approximately 30% require surgical intervention which can range from open reduction with internal fixation (ORIF) to shoulder arthroplasty (including hemiarthroplasty, total shoulder arthroplasty, (TSA) or reverse total shoulder arthroplasty (RTSA)). The aim of this study was to assess trends in operative interventions for PHF in an Australian population.Data was retrospectively collected for patients diagnosed with a PHF and requiring surgical intervention between January 2001 and December 2020. Data for patients undergoing ORIF were extracted from the Medicare database, while data for patients receiving arthroplasty for PHF were obtained from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR).Across the study period, ORIF was the most common surgical procedure for management of PHFs. However, since 2019, RTSA has surpassed ORIF as the most common surgical procedure to treat PHFs, accounting for 51% of operations. While the number of RTSA procedures for PHF has increased, ORIF and shoulder hemiarthroplasty has significantly reduced since 2007 (p < 0.001). TSA has remained uncommon across the follow-up period, accounting for less than 1% of all operations. Patients younger than 65 years were more likely to receive ORIF, while those aged 65 years or greater were more likely to receive hemiarthroplasty or RTSA.While the number of ORIF procedures has increased during the period of interest, it has diminished as a proportion of overall procedure volume. RTSA is becoming increasingly popular, with decreasing utilization of hemiarthroplasty, and TSA for fracture remaining uncommon. These trends provide information that can be used to guide resource allocation and health provision in the future. A comparison to similar data from other nations would be useful.

Early Clinical Outcomes and Complications of Transfibular Total Ankle Arthroplasty: The Australian Experience

We report the short-term outcomes of a retrospective cohort of Trabecular Metal total ankle arthroplasties (TAAs) via a transfibular approach from a single, nondesigner surgeon in Australia. This was a retrospective cohort study. Demographic, clinical, and patient-reported outcome measures (PROMs) were collected. The primary outcome was the Foot and Ankle Outcome Score (FAOS), and secondary outcomes included patient satisfaction, the EuroQol-5 Dimension (EQ5D), and complications including revision rates. Between 2016 and 2019, 84 trabecular metal prostheses were implanted in 84 patients. Mean age (SD) at time of surgery was 68 (7.8) years, and 46 (55%) were male. Mean follow-up (SD) was 26.1 (13) months. There were significant (P < .001) improvements in the FAOS in the subscales of pain (47.9 to 79.1), activities of daily living (59.5 to 83.7), and quality of life (25.5 to 60.2) and EQ-5D (0.55 to 0.75) (P < .001), and overall satisfaction was 69.6%. The commonest complications were wound infection or breakdown (11.9%, n=10), fibular nonunion (3.5%), plate irritation (3.5%), and tibial nerve neuropathy (3.5%). There were no thromboembolic complications. Implant survivorship was 100%, with Trabecular Metal components retained in all patients. Two patients developed deep infection, with 1 requiring debridement and polyethylene exchange. No patients experienced implant loosening. Our results demonstrate that the trabecular metal survival rates are comparable with other total ankle implants in the Australian Orthopaedic Association National Joint Replacement Registry and as published in other international literature. Overall patient satisfaction was high, as were PROMs. However, the data highlight potential complications uniquely associated with this implant. The authors believe that these figures support TAA via a transfibular approach as a viable option in the treatment of ankle arthritis. Level IV, retrospective cohort study.

Early Revision Rates of Total Hip Arthroplasty Using the Intellijoint HIP Computer Navigation System: A Study From the Australian National Joint Replacement Registry of 1911 Procedures.

Total hip arthroplasty (THA) is an effective treatment for symptomatic hip osteoarthritis. The aim of this study was to determine the revision outcome of commercially available navigation technologies. Data from the Australian Orthopaedic Association National Joint Replacement Registry from January 2016 to December 2020 included all primary THA procedures performed for osteoarthritis. Procedures using the Intellijoint HIP navigation system were identified and compared to procedures using "other" computer navigation systems and to nonnavigated procedures. The cumulative percent revision (CPR) was compared between the 3 groups using Kaplan-Meier estimates of survivorship and hazard ratios from Cox proportional hazards models, adjusted for age and gender. There were 1911 procedures that used the Intellijoint system, 4081 used "other" computer navigation systems, and 160,661 were nonnavigated procedures. The all-cause 2-year CPR rate for the Intellijoint system was 1.8% (95% confidence interval [CI], 1.2-2.6), compared to 2.2% (95% CI, 1.8-2.8) for other navigated cases and 2.2% (95% CI, 2.1-2.3) for nonnavigated cases. A prosthesis analysis identified the Paragon/Acetabular Shell THAs combined with the Intellijoint system to have a higher (3.4%) rate of revision than nonnavigated THAs (hazard ratio= 2.00 [95% CI, 1.01-4.00], P= .048). When this combination was excluded, the Intellijoint group demonstrated a 2-year CPR of 1.3%. There was no statistical difference in the CPR between the 3 groups before or after excluding the Paragon/Acetabular Shell system. The preliminary data presented demonstrate no statistical difference in all-cause revision rates when comparing the Intellijoint system with "other" navigation systems and "nonnavigated" approaches for primary THAs. III (National registry analysis).

No increased risk of cancer associated with metal-on-metal or ceramic-on-ceramic procedures compared to other bearing surfaces in patients with total hip arthroplasty: A nationwide linked registry cohort analysis of 167,837 patients.

Studies have identified increased cancer risk among patients undergoing total hip arthroplasty (THA) compared to the general population. However, evidence of all-cause and site-specific cancer risk associated with different bearing surfaces has varied, with previous studies having short latency periods with respect to use of modern Metal-on-Metal (MoM) bearings. Using the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) linked to Australasian Association of Cancer Registries data, our aim was to evaluate risk of all-cause and site-specific cancer according to bearing surfaces in patients undergoing THA for osteoarthritis and whether risk increased with MoM bearings. Standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) were calculated by comparing number of observed cancer cases to expected number based on incidence rate in the Australian population. All-cause and site-specific cancer rates were calculated for all conventional stemmed THA (csTHA) and resurfacing THA (rsTHA) procedures performed for osteoarthritis. Cox proportional hazards models were used to compare cancer rates for MoM, ceramic-on-ceramic (CoC) and resurfacing procedures with a comparison group comprising metal-on-polyethylene (MoP) or ceramic-on-polyethylene (CoP) procedures. There were 156,516 patients with csTHA procedures and 11,321 with rsTHA procedures for osteoarthritis performed between 1999 and 2012. Incidence of all-cause cancer was significantly higher for csTHA (SIR 1.24, 95% CI 1.22-1.26) and rsTHA (SIR 1.74, 95% CI 1.39-2.04) compared to the Australian population. For csTHA, there was no significant difference in all-site cancer rates for MoM (Hazard Ratio (HR) 1.01, 95%CI 0.96-1.07) or CoC (HR 0.98, 95%CI 0.94-1.02) compared to MoP and CoP bearings. Significantly increased risk of melanoma, non-Hodgkins lymphoma, myeloma, leukaemia, prostate, colon, bladder and kidney cancer was found for csTHA and, prostate cancer, melanoma for rsTHA procedures when compared to the Australian population, although risk was not significantly different across bearing surfaces. csTHA and rsTHA procedures were associated with increased cancer incidence compared to the Australian population. However, no excess risk was observed for MoM or CoC procedures compared to other bearing surfaces.

Total shoulder replacement stems in osteoarthritis-short, long, or reverse? An analysis of the impact of crosslinked polyethylene.

The 2021 Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) report indicated that total shoulder replacement using both midhead (TMH) length humeral components and reverse arthroplasty (RTSA) had a lower revision rate than stemmed humeral components in anatomic total shoulder arthroplasty (aTSA)-for all prosthesis types and diagnoses. However, there are many factors that affect the outcome of total shoulder replacement, including stem length and polarity, polyethylene type, and glenoid fixation (cemented vs. cementless). The aim of this study was to assess the impact of these variables in the various primary total arthroplasty alternatives for osteoarthritis (OA) in the shoulder. Data from a large national arthroplasty registry were analyzed for the period April 2004 to December 2020. The study population included all primary aTSA, RTSA, and TMH shoulder arthroplasty procedures undertaken for OA using either crosslinked polyethylene (XLPE) or noncrosslinked polyethylene (non-XLPE). Because of the previously documented and reported higher revision rate compared with other anatomic total shoulder replacement options, those using cementless metal-backed glenoid components were excluded. The rate of revision was determined by Kaplan-Meier estimates, with comparisons by Cox proportional hazard models. Reasons for revision were also assessed. For a primary diagnosis of OA, aTSA with a cemented XLPE glenoid component had the lowest revision rate, with a 12-year cumulative revision rate of 4.7%, compared with aTSA with cemented non-XLPE glenoid component at 8.7% and RTSA at 6.8%. The revision rate for TMH (with XLPE or non-XLPE) was lower than aTSA with cemented non-XLPE but was similar to the other implants at the same length of follow-up. The reason for revision of cemented aTSR was most commonly component loosening, not rotator cuff deficiency. Long-stem humeral components matched with XLPE in aTSA achieve a lower revision rate compared with shorter stems, long stems with conventional polyethylene, and RTSA when used to treat shoulder OA. In all these cohorts, loosening, not rotator cuff failure, was the most common diagnosis for revision.

Antibiotic utilisation in primary and revision total hip replacement patients: A registry linkage cohort study of 106 253 patients using the Australian Orthopaedic Association National Joint Replacement Registry.

Infection is a major complication following joint replacement (JR) surgery. However, little data exist regarding antibiotic utilisation following primary JR and how use changes with subsequent revision surgery. This study aimed to examine variation in antibiotic utilisation rates before and after hip replacement surgery in those revised for infection, revised for other reasons and those without revision. This retrospective cohort analysis used linked data from the Australian Orthopaedic Association National Joint Replacement Registry and Australian Government Pharmaceutical Benefits Scheme. Patients were included if undergoing total hip replacement (THR) for osteoarthritis in private hospitals between 2002 and 2017. Three groups were examined: primary THR with no subsequent revision (n=102 577), primary THR with a subsequent revision for reasons other than periprosthetic joint infection (PJI) (n=3156) and primary THR with a subsequent revision for PJI (n=520). Monthly antibiotic utilisation rates and prevalence rate ratios (PRRs) with 95% confidence intervals (CIs) were calculated in the 2 years pre- and post-THR. Prior to primary THR antibiotic utilisation was 9%-10%. After primary THR, antibiotic utilisation rates were higher among patients revised for PJI (PRR 1.69, 95% CI 1.60-1.79) compared to non-revised patients, while the utilisation rate was lower in patients revised for reasons other than infection (PRR 0.96, 95% CI 0.93-0.98). For those revised for infection, antibiotic utilisation post-revision surgery was two times higher than those revised for other reasons (PRR 2.16, 95% CI 2.08-2.23). Utilisation of injectable antibiotics including, vancomycin, flucloxacillin and cephazolin was higher in those revised for PJI patients 0-2 weeks following surgery but not in those revised for other reasons compared to the non-revised group. Ongoing antibiotic utilisation after primary surgery may be an early signal of problems with the THR and should be a prompt for primary care physicians to refer patients to specialists for further appropriate investigations and management.

Dual mobility versus conventional total hip arthroplasty in femoral neck fractures (DISTINCT): protocol for a registry-nested, open-label, cluster-randomised crossover trial

IntroductionHip fractures treated with total hip arthroplasty (THA) are at high risk of prosthesis instability, and dislocation is the most common indication for revision surgery. This study aims to determine...

Estimating incidence rates of periprosthetic joint infection after hip and knee arthroplasty for osteoarthritis using linked registry and administrative health data.

The aim of this study was to estimate the 90-day periprosthetic joint infection (PJI) rates following total knee arthroplasty (TKA) and total hip arthroplasty (THA) for osteoarthritis (OA). This was a data linkage study using the New South Wales (NSW) Admitted Patient Data Collection (APDC) and the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), which collect data from all public and private hospitals in NSW, Australia. Patients who underwent a TKA or THA for OA between 1 January 2002 and 31 December 2017 were included. The main outcome measures were 90-day incidence rates of hospital readmission for: revision arthroplasty for PJI as recorded in the AOANJRR; conservative definition of PJI, defined by T84.5, the PJI diagnosis code in the APDC; and extended definition of PJI, defined by the presence of either T84.5, or combinations of diagnosis and procedure code groups derived from recursive binary partitioning in the APDC. The mean 90-day revision rate for infection was 0.1% (0.1% to 0.2%) for TKA and 0.3% (0.1% to 0.5%) for THA. The mean 90-day PJI rates defined by T84.5 were 1.3% (1.1% to 1.7%) for TKA and 1.1% (0.8% to 1.3%) for THA. The mean 90-day PJI rates using the extended definition were 1.9% (1.5% to 2.2%) and 1.5% (1.3% to 1.7%) following TKA and THA, respectively. When reporting the revision arthroplasty for infection, the AOANJRR substantially underestimates the rate of PJI at 90 days. Using combinations of infection codes and PJI-related surgical procedure codes in linked hospital administrative databases could be an alternative way to monitor PJI rates.Cite this article: Bone Joint J2022;104-B(9):1060-1066.

CORR Insights®: Reduced Revision Rates in Total Shoulder Arthroplasty With Crosslinked Polyethylene: Results From the Australian Orthopaedic Association National Joint Replacement Registry.

CORR Insights®: Reduced Revision Rates in Total Shoulder Arthroplasty With Crosslinked Polyethylene: Results From the Australian Orthopaedic Association National Joint Replacement Registry.

Primary inlay reverse shoulder arthroplasty has a higher rate of revision than onlay reverse shoulder arthroplasty: Analysis from the Australian Orthopaedic Association National Joint Replacement Registry.

Two classes of primary reverse total shoulder arthroplasty (rTSA), inlay (in-rTSA), and onlay (on-rTSA) were compared to determine differences in rates of revision. Between 1 January 2012 and 31 December 2020, all primary in-rTSA or on-rTSA procedures were compared from a large national arthroplasty registry by cumulative percentage revision (CPR). Kaplan-Meier estimates of survivorship and hazard ratios from Cox proportional hazard models adjusted for age, gender, glenosphere size, and humeral fixation determined any associations to the risk of revision. Of the 14,807 in-rTSA and 6590 on-rTSA procedures, the CPR at seven years was 4.9%. There was an increased risk of revision for in-rTSA vs on-rTSA (p = 0.039) when adjusted for age, gender, glenosphere size, and humeral fixation. Glenosphere size <38 mm adjusted for age and gender (p = 0.016) increased the revision risk. Revision for instability/dislocation occurred more often for in-rTSA vs on-rTSA (p < 0.001) in the first three months. Males had a higher rate of revision than females for in-rTSA (3months+, p = 0.001) and for on-rTSA (p < 0.001). Care should be taken when considering in-rTSA particularly in males, and if preoperative planning suggests a small (<38 mm) glenosphere. Level III, therapeutic study. Original article.

CORR Insights®: Poor Knee-specific and Generic Patient-reported Outcome Measure Scores at 6 Months Are Associated With Early Revision Knee Arthroplasty: A Study From the Australian Orthopaedic Association National Joint Replacement Registry.

CORR Insights®: Poor Knee-specific and Generic Patient-reported Outcome Measure Scores at 6 Months Are Associated With Early Revision Knee Arthroplasty: A Study From the Australian Orthopaedic Association National Joint Replacement Registry.

What Is the Outcome of the First Revision Procedure of Primary THA for Osteoarthritis? A Study From the Australian Orthopaedic Association National Joint Replacement Registry.

Joint arthroplasty registries traditionally report survivorship outcomes mainly on primary joint arthroplasty. The outcome of first revision procedures is less commonly reported, because large numbers of primary procedures are required to analyze a sufficient number of first revision procedures. Additionally, adequate linkage of primary procedures to revisions and mortality is required. When undertaking revision hip surgery, it is important for surgeons to understand the outcomes of these procedures to better inform patients. Using data from a large national joint registry, we asked: (1) What is the overall rate of revision of the first aseptic revision procedure for a primary THA? (2) Does the rate of revision of the first revision vary by the diagnosis for the first revision? (3) What is the mortality after the first revision, and does it vary by the reason for first revision? The Australian Orthopaedic Association National Joint Replacement Registry longitudinally maintains data on all primary and revision joint arthroplasties, with nearly 100% capture. The analyses for this study were performed on primary THA procedures in patients with a diagnosis of osteoarthritis up to December 31, 2020, who had undergone subsequent revision. We excluded all primary THAs involving metal-on-metal and ceramic-on-metal bearing surfaces and prostheses with exchangeable necks because these designs may have particular issues associated with revisions, such as extensive soft tissue destruction, that are not seen with conventional bearings, making a comparative analysis of the first revision involving these bearing surfaces more complicated. Metal-on-metal bearing surfaces have not been used in Australia since 2017. We identified 17,046 first revision procedures from the above study population and after exclusions, included 13,713 first revision procedures in the analyses. The mean age at the first revision was 71 ± 11 years, and 55% (7496 of 13,713) of the patients were women. The median (IQR) time from the primary procedure to the first revision was 3 years (0.3 to 7.3), ranging from 0.8 years for the diagnosis of dislocation and instability to 10 years for osteolysis. There was some variation depending on the reason for the first revision. For example, patients undergoing revision for fracture were slightly older (mean age 76 ± 11 years) and patients undergoing revision for dislocation were more likely to be women (61% [2213 of 3620]). The registry has endeavored to standardize the sequence of revisions and uses a numerical approach to describe revision procedures. The first revision is the revision of a primary procedure, the second revision is the revision of the first revision, and so on. We therefore described the outcome of the first revision as the cumulative percent second revision. The outcome measure was the cumulative percent revision, which was defined using Kaplan-Meier estimates of survivorship to describe the time to the second revision. Hazard ratios from Cox proportional hazards models, adjusting for age and gender, were performed to compare the revision rates among groups. When possible, the cumulative percent second revision at the longest follow-up timepoint was determined with the available data, and when there were insufficient numbers, we used appropriate earlier time periods. The cumulative percent second revision at 18 years was 26% (95% confidence interval [CI] 24% to 28%). When comparing the outcome of the first revision by reason, prosthesis dislocation or instability had the highest rate of second revision compared with the other reasons for first revision. Dual-mobility prostheses had a lower rate of second revision for dislocation or instability than head sizes 32 mm or smaller and when compared to constrained prostheses after 3 months. There was no difference between dual-mobility prostheses and head sizes larger than 32 mm. There were no differences in the rate of second revision when first revisions for loosening, periprosthetic fracture, and osteolysis were compared. If cemented femoral fixation was performed at the time of the first revision, there was a higher cumulative percent second revision for loosening than cementless fixation from 6 months to 6 years, and after this time, there was no difference. The overall mortality after a first revision of primary conventional THA was 1% at 30 days, 2% at 90 days, 5% at 1 year, and 40% at 10 years. A first revision for periprosthetic fracture had the highest mortality at all timepoints compared with other reasons for the first revision. Larger head sizes and dual-mobility cups may help reduce further revisions for dislocation, and the use of cementless stems for a first revision for loosening seems advantageous. Surgeons may counsel patients about the higher risk of death after first revision procedures, particularly if the first revision is performed for periprosthetic fracture.Level of Evidence Level III, therapeutic study.

What’s New in Hip Replacement

What’s New in Hip Replacement

Is the Revision Rate for Femoral Neck Fracture Lower for Total Hip Arthroplasty Than for Hemiarthroplasty?: A Comparison of Registry Data for Contemporary Surgical Options.

When arthroplasty is indicated for a femoral neck fracture (FNF), it is unclear whether total hip arthroplasty (THA) or hemiarthroplasty (HA) is best. This study compares data from the Australian Orthopaedic Association National Joint Replacement Registry using contemporary surgical options. Patients from 60 to 85 years old who were treated with arthroplasty for FNF, between September 1999 and December 2019, were included if the femoral stems were cemented. Only THAs with femoral heads of ≥36 mm or dual-mobility articulations were included. Patients who had monoblock HA were excluded. Rates of revision for all aseptic failures and dislocation were compared. Competing risks of revision and death were considered using the cumulative incidence function. Subdistribution hazard ratios (HRs) for revision or death from a Fine-Gray regression model were used to compare THA and HA. Interactions of procedure with age group and sex were considered. Secondary analysis adjusting for body mass index (BMI) and American Society of Anesthesiologists (ASA) classification was also considered. There were 4,551 THA and 29,714 HA procedures included. The rate of revision for THA was lower for women from 60 to 69 years old (HR = 0.58 [95% confidence interval (CI), 0.39 to 0.85]) and from 70 to 74 years old (HR = 0.65 [95% CI, 0.43 to 0.98]) compared with HA. However, women from 80 to 85 years old (HR = 1.56 [95% CI, 1.03 to 2.35]) and men from 75 to 79 years old (HR = 1.61 [95% CI, 1.05 to 2.46]) and 80 to 85 years old (HR = 2.73 [95% CI, 1.89 to 3.95]) had an increased rate of revision when THA was undertaken compared with HA. There was no difference in the rate of revision for dislocation between THA and HA for either sex or age categories. When contemporary surgical options for FNF are used, there is a benefit with respect to revision outcomes for THA in women who are <75 years old and a benefit for HA in women who are ≥80 years old and men who are ≥75 years old. There is no difference in dislocation rates. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Modular dual-mobility articulations in patients with adverse spinopelvic mobility

Aims Adverse spinal motion or balance (spine mobility) and adverse pelvic mobility, in combination, are often referred to as adverse spinopelvic mobility (SPM). A stiff lumbar spine, large posterior standing pelvic tilt, and severe sagittal spinal deformity have been identified as risk factors for increased hip instability. Adverse SPM can create functional malposition of the acetabular components and hence is an instability risk. Adverse pelvic mobility is often, but not always, associated with abnormal spinal motion parameters. Dislocation rates for dual-mobility articulations (DMAs) have been reported to be between 0% and 1.1%. The aim of this study was to determine the early survivorship from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) of patients with adverse SPM who received a DMA. Methods A multicentre study was performed using data from 227 patients undergoing primary total hip arthroplasty (THA), enrolled consecutively. All the patients who had one or more adverse spine or pelvic mobility parameter had a DMA inserted at the time of their surgery. The mean age was 76 years (22 to 93) and 63% were female (n = 145). At a mean of 14 months (5 to 31) postoperatively, the AOANJRR was analyzed for follow-up information. Reasons for revision and types of revision were identified. Results The AOANJRR reported two revisions: one due to infection, and the second due to femoral component loosening. No revisions for dislocation were reported. One patient died with the prosthesis in situ. Kaplan-Meier survival rate was 99.1% (95% confidence interval 98.3 to 100) at 14 months (number at risk 104). Conclusion In our cohort of patients undergoing primary THA with one or more factor associated with adverse SPM, DM bearings conferred stability at two years’ follow-up. Cite this article: Bone Joint J 2022;104-B(7):820–825.

Poor Knee-specific and Generic Patient-reported Outcome Measure Scores at 6 Months Are Associated With Early Revision Knee Arthroplasty: A Study From the Australian Orthopaedic Association National Joint Replacement Registry.

The ability to identify which patients are at a greater risk of early revision knee arthroplasty has important practical and resource implications. Many international arthroplasty registries administer patient-reported outcome measures (PROMs) to provide a holistic assessment of pain, function, and quality of life. However, few PROM scores have been evaluated as potential indicators of early revision knee arthroplasty, and earlier studies have largely focused on knee-specific measures. This national registry-based study asked: (1) Which 6-month postoperative knee-specific and generic PROM scores are associated with early revision knee arthroplasty (defined as revision surgery performed 6 to 24 months after the primary procedure)? (2) Is a clinically important improvement in PROM scores (based on thresholds for the minimal important change) after primary knee arthroplasty associated with a lower risk of early revision? Preoperative and 6-month postoperative PROM scores for patients undergoing primary knee arthroplasty were sourced from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and Arthroplasty Clinical Outcomes Registry National. Between January 2013 and December 2020, PROM data were available for 19,402 primary total knee arthroplasties; these data were linked to AOANJRR data on revision knee arthroplasty. Of these, 3448 procedures were excluded because they did not have 6-month PROM data, they had not reached the 6-month postoperative point, they had died before 24 months, or they had received revision knee arthroplasty before the 6-month PROMs assessment. After these exclusions, data were analyzed for 15,954 primary knee arthroplasties. Associations between knee-specific (knee pain, Oxford Knee Score, and 12-item Knee injury and Osteoarthritis Outcome Score [KOOS-12]) or generic PROM scores (5-level EuroQol quality of life instrument [EQ-5D], EQ VAS, perceived change, and satisfaction) and revision surgery were explored using t-tests, chi-square tests, and regression models. Ninety-four revision procedures were performed at 6 to 24 months, most commonly for infection (39% [37 procedures]). The early revision group was younger than the unrevised group (mean age 64 years versus 68 years) and a between-group difference in American Society of Anesthesiologists (ASA) grade was noted. Apart from a small difference in preoperative low back pain for the early revision group (mean low back pain VAS 4.2 points for the early revision group versus 3.3 points for the unrevised group), there were no between-group differences in preoperative knee-specific or generic PROM scores on univariate analysis. As the inclusion of ASA grade or low back pain score did not alter the model results, the final multivariable model included only the most clinically plausible confounders (age and gender) as covariates. Multivariable models (adjusting for age and gender) were also used to examine the association between a clinically important improvement in PROM scores (based on published thresholds for minimal important change) and the likelihood of early revision. After adjusting for age and gender, poor postoperative knee pain, Oxford, KOOS-12, EQ-5D, and EQ VAS scores were all associated with early revision. A one-unit increase (worsening) in knee pain at 6 months was associated with a 31% increase in the likelihood of revision (RR 1.31 [95% confidence interval (CI) 1.19 to 1.43]; p < 0.001). Reflecting the reversed scoring direction, a one-unit increase (improvement) in Oxford or KOOS-12 score was associated with a 9% and 5% reduction in revision risk, respectively (RR for Oxford: 0.91 [95% CI 0.90 to 0.93]; p < 0.001; RR for KOOS-12 summary: 0.95 [95% CI 0.94 to 0.97]; p < 0.001). Patient dissatisfaction (RR 6.8 [95% CI 3.7 to 12.3]) and patient-perceived worsening (RR 11.7 [95% CI 7.4 to 18.5]) at 6 months were also associated with an increased likelihood of early revision. After adjusting for age and gender, patients who did not achieve a clinically important improvement in PROM scores had a higher risk of early revision (RR 2.9 for the knee pain VAS, RR 4.2 for the Oxford Knee Score, RR 6.3 to 8.6 for KOOS-12, and RR 2.3 for EQ-5D) compared with those who did (reference group). Knee-specific and generic PROM scores offer an efficient approach to identifying patients at greater risk of early revision surgery, using either the 6-month score or the magnitude of improvement. These data indicate that surgeons can use single- and multi-item measures to detect a patient-perceived unsuccessful surgical outcome at 6 months after primary knee arthroplasty. Surgeons should be alert to poor PROM scores at 6 months or small improvements in scores (for example, less than 2 points for knee pain VAS or less than 10.5 points for Oxford Knee Score), which signal a need for direct patient follow-up or expedited clinical review. Level III, therapeutic study.

Reduced Revision Rates in Total Shoulder Arthroplasty With Crosslinked Polyethylene: Results From the Australian Orthopaedic Association National Joint Replacement Registry.

Loss of glenoid fixation is a key factor affecting the survivorship of primary total shoulder arthroplasty (TSA). It is not known whether the lower revision rates associated with crosslinked polyethylene (XLPE) compared with those of non-XLPE identified in hip and knee arthroplasty apply to shoulder arthroplasty. We used data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) to compare the revision rates of primary stemmed anatomic TSA using XLPE to procedures using non-XLPE. In patients receiving a primary stemmed anatomic TSA for osteoarthritis, we asked: (1) Does the rate of revision or reason for revision vary between XLPE and non-XLPE all-polyethylene glenoid components? (2) Is there any difference in the revision rate when XLPE is compared with non-XLPE across varying head sizes? (3) Is there any difference in survival among prosthesis combinations with all-polyethylene glenoid components when they are used with XLPE compared with non-XLPE? Data were extracted from the AOANJRR from April 16, 2004, to December 31, 2020. The AOANJRR collects data on more than 97% of joint replacements performed in Australia. The study population included all primary, stemmed, anatomic TSA procedures performed for osteoarthritis using all-polyethylene glenoid components. Procedures were grouped into XLPE and non-XLPE bearing surfaces for comparison. Of the 10,102 primary stemmed anatomic TSAs in the analysis, 39% (3942 of 10,102) used XLPE and 61% (6160 of 10,102) used non-XLPE. There were no differences in age, gender, or follow-up between groups. Revision rates were determined using Kaplan-Meier estimates of survivorship to describe the time to the first revision, with censoring at the time of death or closure of the database at the time of analysis. Revision was defined as removal, replacement, or addition of any component of a joint replacement. The unadjusted cumulative percent revision after the primary arthroplasty (with 95% confidence intervals [CIs]) was calculated and compared using Cox proportional hazard models adjusted for age, gender, fixation, and surgeon volume. Further analyses were performed stratifying according to humeral head size, and a prosthesis-specific analysis adjusted for age and gender was also performed. This analysis was restricted to prosthesis combinations that were used at least 150 times, accounted for at least four revisions, had XLPE and non-XLPE options available, and had a minimum of 3 years of follow-up. Non - XLPE had a higher risk of revision than XLPE after 1.5 years (HR 2.3 [95% CI 1.6 to 3.1]; p < 0.001). The cumulative percent revision at 12 years was 5% (95% CI 4% to 6%) for XLPE and 9% (95% CI 8% to 10%) for non-XLPE. There was no difference in the rate of revision for head sizes smaller than 44 mm. Non-XLPE had a higher rate of revision than XLPE for head sizes 44 to 50 mm after 2 years (HR 2.3 [95% CI 1.5 to 3.6]; p < 0.001) and for heads larger than 50 mm for the entire period (HR 2.2 [95% CI 1.4 to 3.6]; p < 0.001). Two prosthesis combinations fulfilled the inclusion criteria for the prosthesis-specific analysis. One had a higher risk of revision when used with non-XLPE compared with XLPE after 1.5 years (HR 3.7 [95% CI 2.2 to 6.3]; p < 0.001). For the second prosthesis combination, no difference was found in the rate of revision between the two groups. These AOANJRR data demonstrate that noncrosslinked, all-polyethylene glenoid components have a higher revision rate compared with crosslinked, all-polyethylene glenoid components when used in stemmed anatomic TSA for osteoarthritis. As polyethylene type is likely an important determinant of revision risk, crosslinked polyethylene should be used when available, particularly for head sizes larger than 44 mm. Further studies will need to be undertaken after larger numbers of shoulder arthroplasties have been performed to determine whether this reduction in revision risk associated with XLPE bears true for all TSA designs. Level III, therapeutic study.