Australian Orthopaedic Association National Joint Research Articles

Bipolar Hemiarthroplasty Does Not Result in a Higher Risk of Revision Compared with Total Hip Arthroplasty for Displaced Femoral Neck Fractures: An Instrumental Variable Analysis of 36,118 Procedures from the Australian Orthopaedic Association National Joint Replacement Registry.

Previous randomized studies have suggested that there is no short-term difference between the risk of revision following total hip arthroplasty (THA) and hemiarthroplasty (HA) for hip fracture in elderly patients. The aim of the present study was to compare the long-term revision rates of primary THA and HA for femoral neck fracture in order to determine whether unipolar or bipolar HA increases the all-cause risk of revision in patients 50 to 79 years old. Data for 36,188 patients who underwent primary arthroplasty, including 13,035 unipolar and 8,220 bipolar HAs and 14,863 THAs, from September 1, 1999, to December 31, 2019, were obtained from the Australian Orthopaedic Association National Joint Replacement Registry. Unadjusted analyses were performed, as well as analyses adjusted for age, sex, femoral cement, and procedure year. The primary outcome was time to first revision for any cause. Secondary analyses were performed for the reason for revision (i.e., infection, dislocation, and periprosthetic fracture). Instrumental variable analysis of hospital preference (for either HA or THA) was performed in order to mitigate the effect of any unmeasured confounding. All analyses were restricted to hospitals performing at least 10 procedures in the prior year. A total of 18,955 procedures were available for the comparison of modular unipolar HA to THA. Both the adjusted analysis performed with use of Cox proportional hazards (hazard ratio [HR], 1.94; 95% confidence interval [CI], 1.64 to 2.31; p < 0.001) and the instrumental variable analysis (HR, 2.82; 95% CI, 1.89 to 4.22; p < 0.001) demonstrated a higher risk of revision following modular unipolar HA compared with THA from 3 months postoperatively. A total of 13,168 procedures were available for the comparison of bipolar HA to THA. The adjusted analysis performed with use of Cox proportional hazards showed a significantly higher risk of revision for bipolar HA (HR, 1.29; 95% CI, 1.08 to 1.54; p = 0.01). The instrumental variable analysis showed a similar effect size that was not significant (HR, 1.27; 95% CI, 0.91 to 1.78; p = 0.16). Bipolar HA and THA demonstrated no significant difference in revision risk at long-term follow-up. Unipolar HA demonstrated higher risk of revision from 3 months postoperatively compared to THA. The higher risk of revision for dislocation observed following THA may be offset by the higher risk of revision for acetabular erosion or pain following bipolar HA, resulting in more equivalent revision risk. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

CORR Insights®: Small Random Angular Variations in Pelvic Tilt and Lower Extremity Can Cause Error In Static Image-based Preoperative Hip Arthroplasty Planning: A Computer Modeling Study.

CORR Insights®: Small Random Angular Variations in Pelvic Tilt and Lower Extremity Can Cause Error In Static Image-based Preoperative Hip Arthroplasty Planning: A Computer Modeling Study.

CORR Insights®: In Revision THA, Is the Re-revision Risk for Dislocation and Aseptic Causes Greater in Dual-mobility Constructs or Large Femoral Head Bearings? A Study from the Australian Orthopaedic Association National Joint Replacement Registry.

1Associate Attending Orthopedic Surgeon, Hospital for Special Surgery, New York, NY, USA M. L. Parks, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA, Email: [email protected] This CORR Insights® is a commentary on the article “In Revision THA, Is the Re-revision Risk for Dislocation and Aseptic Causes Greater in Dual-mobility Constructs or Large Femoral Head Bearings? A Study from the Australian Orthopaedic Association National Joint Replacement Registry” by Hoskins and colleagues available at:10.1097/CORR.0000000000002085. The author certifies receipt of personal payments or benefits in an amount of USD 10,000 to 100,000 from Zimmer Biomet unrelated to this work. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writer, and do not reflect the opinion or policy of CORR® or The Association of Bone and Joint Surgeons®.

Association between socioeconomic status and joint replacement of the hip and knee: a population-based cohort study of older adults in Tasmania.

A socioeconomic gradient exists in the utilisation of total hip replacements (THR) and total knee replacements (TKR) for osteoarthritis. However, the relations between socioeconomic status (SES) and time to THR or TKR is unknown. To describe the association between SES and time to THR and TKR. One thousand and seventy-two older adults residing in Tasmania, Australia, were studied. Incident primary THR and TKR were determined by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry. At baseline, each participant's area-level SES was determined using the Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD) from the Australian Bureau of Statistics' 2001 census data. The IRSAD was analysed in two ways: (i) categorised into quartiles, whereby quartile 1 represented the most socioeconomically disadvantaged group; and (ii) the cohort dichotomised at the quartile 1 cut-point. The mean age was 63.0 (±7.5) years and 51% were women. Over the median follow up of 12.9 (interquartile range: 12.2-13.9) years, 56 (5%) participants had a THR and 79 (7%) had a TKR. Compared with the most disadvantaged quartile, less disadvantaged participants were less likely to have a THR (i.e. less disadvantaged participants had a longer time to THR; hazard ratio (HR): 0.56; 95% confidence interval (CI) 0.32, 1.00) but not TKR (HR: 0.90; 95% CI 0.53, 1.54). However, the former became non-significant after adjustment for pain and radiographic osteoarthritis, suggesting that the associations may be mediated by these factors. The present study suggests that time to joint replacement was determined according to the symptoms/need of the participants rather than their SES.

Revision for Aseptic Loosening of Highly Porous Acetabular Components in Primary Total Hip Arthroplasty: An Analysis of 20,993 Total Hip Replacements.

Highly porous-coated titanium acetabular components have a high coefficient of friction and ultraporous surfaces to enhance bone ingrowth and osseointegration in total hip arthroplasty (THA). There have been concerns with the development of early radiolucent lines and aseptic loosening of highly porous acetabular components. It is unclear whether these concerns relate to a specific implant or the entire class. The aim of this study is to compare the revision rates for aseptic loosening of highly porous acetabular combinations in primary THA using data from a large joint replacement registry. Data were retrieved from the Australian Orthopedic Association National Joint Replacement Registry for the study period September 1999 to December 2019. All primary THA procedures recorded and performed for osteoarthritis using the most common combinations for each highly porous acetabular component with highly cross-linked polyethylene and a 32-mm or 36-mm femoral head were included. The primary outcome measure was revision for aseptic loosening of the acetabular component. Results were adjusted for patient age and gender. There were 20,993 primary THA procedures performed for osteoarthritis using a highly porous acetabular component across 6 combinations. Relative to the POLARSTEM/R3 (StikTite), the Exeter V40/Tritanium had a significantly higher risk of revision for aseptic loosening of the acetabular component (hazard ratio 0.21, 95% confidence interval 0.06-0.74, P= .014). There was no difference between any other highly porous acetabular component combination and no late revisions for aseptic loosening. Highly porous-coated titanium acetabular components have low rates of aseptic loosening with long-term follow-up. A difference between components may exist. Level III.

How Should Antibiotics Be Used in Primary and Revision Hip and Knee Arthroplasty? An Introduction

Joint arthroplasty is a highly successful surgical treatment for symptomatic arthritis of the hip and knee. Despite excellent pain relief and prosthesis survival of approximately 90% at 20 years, complications occur [[1]Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR)Hip, Knee & Shoulder Arthroplasty: 2021 Annual Report. AOA, Adelaide2021: 1-432https://aoanjrr.sahmri.com/annual-reports-2021Google Scholar]. Deep periprosthetic joint infection (PJI) is among the top 2 causes of failure around the world after primary and revision, hip and knee replacement at both short-term and long-term follow-up [1Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR)Hip, Knee & Shoulder Arthroplasty: 2021 Annual Report. AOA, Adelaide2021: 1-432https://aoanjrr.sahmri.com/annual-reports-2021Google Scholar, 2Meyer J.A. Zhu M. Cavadino A. Coleman B. Munro J.T. Young S.W. Infection and periprosthetic fracture are the leading causes of failure after aseptic revision total knee arthroplasty.Arch Orthop Trauma Surg. 2021; 141: 1373-1383Crossref PubMed Scopus (9) Google Scholar, 3Le D.H. Goodman S.B. Maloney W.J. Huddleston J.I. Current modes of failure in TKA: infection, instability, and stiffness predominate.Clin Orthop Relat Res. 2014; 472: 2197-2200Crossref PubMed Scopus (183) Google Scholar]. In distinction to many other problems, such as dislocation and polyethylene wear that can be directly influenced by improvements in surgical technique and prosthesis design, surgeons may find it more frustrating to reduce surgical site infections. It is important to remember that appropriate use of prophylactic antibiotics, introduced over 50 years ago, remains the single most effective intervention available [[4]Burke J.F. The effective period of preventive antibiotic action in experimental incisions and dermal lesions.Surgery. 1961; 50: 161-168PubMed Google Scholar]. In our well-intentioned pursuit of completely eliminating PJI we can sometimes fall victim to the more is better philosophy. Indeed, over the past few years we have seen the introduction of new delivery methods, dosing schedules, and adjunctive products that encourage us to expand our use of prophylactic antibiotics without conclusive evidence. Additionally, our own success has led us to implement change before results from level 1A studies are available. Although PJI remains a persistent concern, the absolute rate of PJI after hip and knee arthroplasty remains low. Consequently, proving the value of new interventions remains problematic due to the large number of patients and extended follow-up duration required for definitive studies [[5]Thompson K.M. Oldenburg W.A. Deschamps C. Rupp W.C. MD Smith C.D. Chasing zero: the drive to eliminate surgical site infections.Ann Surg. 2011; 254: 430-436Crossref PubMed Scopus (65) Google Scholar]. Furthermore, the distinctions among prophylactic, treatment, and suppressive use of antibiotics have become blurred at times. It is important to remember that overuse of antibiotics has potentially significant consequences including the emergence of antibiotic resistance at the individual and societal levels, and individual patient side effects that can have serious consequences, such as acute kidney injury and allergic reaction [[6]Kheir M.M. Dilley J.E. Ziemba-Davis M. Meneghini R.M. The AAHKS clinical research award: extended oral antibiotics prevent periprosthetic joint infection in high-risk cases: 3855 patients with 1-Year follow-up.J Arthroplasty. 2021; 36: S18-S25Abstract Full Text Full Text PDF PubMed Scopus (20) Google Scholar]. In this series of papers, drawn from presentations from the AAHKS Annual Meeting Symposium: Antibiotic Use in Primary and Revision Total Hip and Knee Arthroplasty, we will discuss the most effective uses of antibiotics before, during, and after surgery in order to reduce deep PJI. Each paper, authored by an expert in the field, will summarize the published data and clinical guidelines pertinent to the topic and distill the information to pragmatic advice that is ready for use in your practice. Download .docx (.02 MB) Help with docx files Conflict of Interest Statement for Clarke

Highlights of the 2021 American Joint Replacement Registry Annual Report.

Highlights of the 2021 American Joint Replacement Registry Annual Report.

Crosswalks between the Oxford hip and knee scores and the HOOS-12 and KOOS-12 instruments

To develop and validate bi-directional crosswalks between the Oxford Hip Score (OHS) and HOOS-12 summary impact score, and between the Oxford Knee Score (OKS) and KOOS-12 summary impact score. Data were sourced from the Australian Orthopaedic Association National Joint Replacement Registry Patient-Reported Outcome Measures Program. Patients undergoing primary joint replacement for osteoarthritis who completed the OHS and HOOS-12 or OKS and KOOS-12 instruments were included in the analysis. An equipercentile method was used to create four crosswalks, with the distribution of scores smoothed using log-linear models prior to equating. Crosswalk validity was assessed through comparison of actual vs derived scores, Pearson correlation coefficients, root mean square errors (RMSE) and Bland-Altman plots. Paired OHS/HOOS-12 data and paired OKS/KOOS-12 data were available for 4,513 patients undergoing total hip replacement and 5,942 patients undergoing total knee replacement, respectively. Minimal differences were observed between actual and crosswalk-derived mean scores (actual OHS 27.55 vs derived OHS 27.56; actual HOOS-12 53.28 vs derived HOOS-12 53.31; actual OKS 27.34 vs derived OKS 27.34; actual KOOS-12 50.51 vs derived KOOS-12 50.58). High correlation was observed between actual and derived scores (Pearson's r for hip-specific instruments: 0.943-0.946; Pearson's r for knee-specific instruments: 0.925-0.931). Plotted actual vs mean derived scores also indicated robust concordance across the breadth of the instrument scales. These crosswalks provide close approximations of actual OHS, OKS, HOOS-12 and KOOS-12 scores, as indicated by multiple validation metrics. They offer a resource for clinicians, researchers and arthroplasty registries to support PROMs score conversion and data harmonisation efforts.

There Is No "Free Lunch" with Total Hip Arthroplasty Incisions: It Is the Pathways and the Procedure, Not the Surgical Approach!: Commentary on the article by Wayne Hoskins, MBBS(Hons), FRACS, PhD, et al.: "The Effect of Surgical Approach and Femoral Prosthesis Type on Revision Rates Following Total Hip Arthroplasty. An Analysis of the Most Commonly Utilized Cementless Stems".

Commentary Surgical approach in total hip arthroplasty has been a particularly hot topic recently. The purported benefits of the anterior approach, including a more rapid recovery and better outcomes, are apparent to many patients with an easy Google search. This has seemingly prompted many surgeons to adopt and promote this approach in their practices. Despite this increased awareness and use of the anterior approach, the comparative data that exist seem to paint a different picture. A meta-analysis on the use of this approach in total hip arthroplasty reported no benefit of one surgical approach over another1. A recent Charnley Award-winning paper also showed that there were no differences in outcomes between the anterior and posterior approaches2. So why the big push for the use of this incision? Both fellowship programs and implant companies are promoting this approach, with the latter linking this incision to robotic surgery or marketing traction tables to assist with this approach during surgery. A multicenter study by Meneghini et al. showed that the anterior approach had higher rates of both dislocation and femoral stem revision than either the anterolateral or posterior approaches3. With use of data from the Australian Orthopaedic Association National Joint Replacement Registry, the study by Hoskins et al. highlights similar problems with the anterior approach. Although there was no difference in the cumulative percent revision between the anterior and posterior surgical cohorts, the anterior approach was characterized by a higher rate of femoral revision for either loosening or periprosthetic fracture. The authors also identified apparent differences in outcomes between the 5 cementless stems when the anterior approach was utilized. An earlier study by Hoskins et al. assessed all 3 surgical approaches among a larger number of patients with use of data from the same joint registry. In that study, Hoskins et al. found higher rates of revisions for periprosthetic fracture and femoral loosening among procedures performed via the anterior approach; however, that study of >122,000 patients also showed a higher rate of dislocation among procedures performed via the posterior approach4. Additionally, many of these same authors have also reported on a greater learning curve with the anterior approach5. For the present study by Hoskins et al., conclusions must be tempered with the limitations of the study design, which include statistical problems as a result of comparing only 5 stems. Another concern was the lack of control regarding surgeon experience, which may have affected approach-specific findings. A possible limitation of this study might be selection bias between the 2 cohort patient demographics between the anterior and posterior cohort groups. There is more to take from this study than just the statistics regarding the stem design and the higher femoral-sided complication rate with the anterior approach. First, we have to acknowledge a learning curve with the anterior approach. Is it worth enduring such a learning curve for a surgical approach that has no documented outcomes-related benefits? Second, surgeons need to temper their preference for a particular approach with the realization that overpromising and failing to meet unrealistic expectations is a problem for our profession as a whole. The pathways that have been developed for outpatient surgery and the tremendous long-term track record of total hip arthroplasty are what is driving modern day arthroplasty, not the approach6. All approaches have inherent problems. Promoting 1 approach over another is just marketing without substantial proof of superiority. Sticking with evidence-based medicine should be the highest priority for our patients. We should continue to pursue research models that assess implant design in order to help surgeons utilize their preferred approach, with the end goal of providing the best possible care to each individual patient. Certainly surgical technique, clinical experience, and modern-day pathways play the most substantial roles in providing excellent care during total hip arthroplasty. In the future, surgical residents and fellows may consider becoming familiar with all 3 surgical approaches; however, it is unclear whether the typical case volume would allow proficiency in light of the learning curves of each approach. The goal of teaching programs should be to encourage surgeons to tailor surgical approach on a case-by-case basis in order to achieve the best outcomes. Presently, all surgical approaches allow surgeons to successfully perform this remarkable surgical procedure in an outpatient setting in most healthy patients.

In Revision THA, Is the Re-revision Risk for Dislocation and Aseptic Causes Greater in Dual-mobility Constructs or Large Femoral Head Bearings? A Study from the Australian Orthopaedic Association National Joint Replacement Registry.

Dislocation is one of the most common causes of a re-revision after a revision THA. Dual-mobility constructs and large femoral head bearings (≥ 36 mm) are known options for mitigating this risk. However, it is unknown which of these choices is better for reducing the risk of dislocation and all-cause re-revision surgery. It is also unknown whether there is a difference between dual-mobility constructs and large femoral head bearings according to the size of the acetabular component. We used data from a large national registry to ask: In patients undergoing revision THA for aseptic causes after a primary THA performed for osteoarthritis, (1) Does the proportion of re-revision surgery for prosthesis dislocation differ between revision THAs performed with dual-mobility constructs and those performed with large femoral head bearings? (2) Does the proportion of re-revision surgery for all aseptic causes differ between revision THAs performed with dual-mobility constructs and those performed with large femoral head bearings? (3) Is there a difference when the results are stratified by acetabular component size? Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) were analyzed for 1295 first-revision THAs for aseptic causes after a primary THA performed for osteoarthritis. The study period was from January 2008-when the first dual-mobility prosthesis was recorded-to December 2019. There were 502 dual-mobility constructs and 793 large femoral head bearings. There was a larger percentage of women in the dual-mobility construct group (67% [334 of 502]) compared with the large femoral head bearing group (51% [402 of 793]), but this was adjusted for in the statistical analysis. Patient ages were similar for the dual-mobility construct group (67 ± 11 years) and the large femoral head group (65 ± 12 years). American Society of Anesthesiologists (ASA) class and BMI distributions were similar. The mean follow-up was shorter for dual-mobility constructs at 2 ± 1.8 years compared with 4 ± 2.9 years for large femoral head bearings. The cumulative percent revision (CPR) was determined for a diagnosis of prosthesis dislocation as well as for all aseptic causes (excluding infection). Procedures using metal-on-metal bearings were excluded. The time to the re-revision was described using Kaplan-Meier estimates of survivorship, with right censoring for death or database closure at the time of analysis. The unadjusted CPR was estimated each year of the first 5 years for dual-mobility constructs and for each of the first 9 years for large femoral head bearings, with 95% confidence intervals using unadjusted pointwise Greenwood estimates. The apparent shorter follow-up of the dual-mobility construct group relates to the more recent increase in dual-mobility numbers recorded in the registry. The results were adjusted for age, gender, and femoral fixation. Results were subanalyzed for acetabular component sizes < 58 mm and ≥ 58 mm, set a priori on the basis of biomechanical and other registry data. There was no difference in the proportion of re-revision for prosthesis dislocation between dual-mobility constructs and large femoral head bearings (hazard ratio 1.22 [95% CI 0.70 to 2.12]; p = 0.49). At 5 years, the CPR of the re-revision for prosthesis dislocation was 4.0% for dual mobility constructs (95% CI 2.3% to 6.8%) and 4.1% for large femoral head bearings (95% CI 2.7% to 6.1%). There was no difference in the proportion of all aseptic-cause second revisions between dual-mobility constructs and large femoral head bearings (HR 1.02 [95% CI 0.76 to 1.37]; p = 0.89). At 5 years, the CPR of dual-mobility constructs was 17.6% for all aseptic-cause second revision (95% CI 12.6% to 24.3%) and 17.8% for large femoral head bearings (95% CI 14.9% to 21.2%). When stratified by acetabular component sizes less than 58 mm and at least 58 mm, there was no difference in the re-revision CPR for dislocation or for all aseptic causes between dual-mobility constructs and large femoral head bearings. Either dual-mobility constructs or large femoral head bearings can be used in revision THA, regardless of acetabular component size, as they did not differ in terms of re-revision rates for dislocation and all aseptic causes in this registry study. Longer term follow-up is required to assess whether complications develop with either implant or whether a difference in revision rates becomes apparent. Ongoing follow-up and comparison in a registry format would seem the best way to compare long-term complications and revision rates. Future studies should also compare surgeon factors and whether they influence decision-making between prosthesis options and second revision rates. Nested randomized controlled trials in national registries would seem a viable option for future research. Level III, therapeutic study.

Cemented Polished Tapered Stems Have Lower Revision Rates Than Commonly Used Cementless Implant up to 17 Years of Follow-Up: An Analysis of 201,889 Total Hip Replacements From the Australian Orthopedic Association National Joint Replacement Registry.

Data assessing femoral stems may be influenced by grouping together matt and polished stems, despite their differing reported survivorship. The aim of this study is to assess the difference in revision rates between commonly used cemented and cementless stems when polished tapered stems are assessed independently of matt stems. Australian Orthopaedic Association National Joint Replacement Registry data from 1999 to 2019 were used to assess difference in revision rates between the 5 most commonly implanted femoral cemented and cementless stems for osteoarthritis. Cemented matt femoral stems, stems using line-to-line cementing techniques and procedures using non-cross-linked polyethylene, large head (>32 mm) metal-on-metal bearing surfaces or exchangeable necks were excluded. Cumulative percent revision was used to help compare survivorship between stems. There were 201,889 total hip replacements meeting the inclusion criteria, of which 50.0% were cemented and 50.0% cementless. Cemented stems had a lower rate of revision at all time points compared to cementless stems. This was most significant during the first 2 weeks (hazard ratio 0.48, 95% confidence interval 0.40-0.58, P < .001) compared to 2 weeks postoperatively and onwards (hazard ratio 0.85, 95% confidence interval 0.81-0.90, P < .001). A subanalysis of head size, bearing type, and surgeon volume further supported the use of a cemented stem. Commonly used cemented polished tapered stems have a lower revision rate when compared to commonly used cementless prostheses, and are recommended in all age groups for both low-volume and high-volume surgeons especially when head size 32 mm or smaller is used.

CORR Insights®: What Can We Learn From Surgeons Who Perform THA and TKA and Have the Lowest Revision Rates? A Study from the Australian Orthopaedic Association National Joint Replacement Registry.

CORR Insights®: What Can We Learn From Surgeons Who Perform THA and TKA and Have the Lowest Revision Rates? A Study from the Australian Orthopaedic Association National Joint Replacement Registry.

To Cement or Not to Cement: Have We Answered the Question?: Commentary on an article by Hasan R. Mohammad, MBChB, MRes(Dist), MRCS (Eng), DPhil(Oxon), et al.: "A Matched Comparison of the Long-Term Outcomes of Cemented and Cementless Total Knee Replacements, Based on Data from National Databases. An Analysis from the National Joint Registry of England, Wales, Northern Ireland and the

Commentary The debate regarding the optimal method of fixation in total knee arthroplasty (TKA) has continued for almost 40 years, beginning with case series and culminating recently with intermediate-term results from randomized controlled trials (RCTs). The ongoing interest in this debate is justified: TKA patients are getting younger, making implant longevity a priority; post-TKA dissatisfaction remains prevalent, leading to the question of whether implant fixation contributes to pain; and infection is still the most common reason for revision, prompting the desire to simplify surgery and reduce operative time. The popularity of cementless TKA has very recently increased, as reflected in the 2020 annual reports of the Australian Orthopaedic Association National Joint Replacement Registry and the American Joint Replacement Registry. Yet, to date, there have been few long-term (>10-year) large-scale studies that have investigated the clinical outcomes of cemented versus cementless TKA, while accounting for pertinent variables such as age, body mass index, and bone quality. Mohammad and colleagues have challenged this gap in the literature by conducting a rigorous propensity-score-matched cohort analysis of 22,477 patients treated with cementless TKA and 22,477 patients treated with cemented TKA from 2004 to 2018 with Great Britain’s National Joint Registry (NJR). This is the largest long-term matched analysis of TKA outcomes according to fixation type. Their results can be interpreted differently, depending on where your personal loyalties lie. Cement advocates will point out the lower overall implant survival rate, higher rate of reoperation (but not of component revision), and higher rate of revision for pain associated with cementless TKA. Cement cynics will stress the lower infection rate, lower overall reoperation rate, and lower aseptic loosening rate in patients <65 years of age associated with cementless TKA. Regardless of these differences, the study found that both fixation techniques exhibited a survival probability of >95%. Furthermore, historical concerns associated with cementless fixation, including early loosening and periprosthetic fractures, were not observed, nor were older designs associated with higher failure rates. Are the above results enough to encourage the masses to abandon cement in primary TKA? In isolation, probably not. However, the mounting evidence creates a compelling argument. Over the last 10 years, 6 separate RCTs comparing fixation techniques have found little difference in revision rates or survival1-6, at least in the short term. Does the internal consistency of each of these trials apply to your clinical practice? Not universally, but for a young patient who presents with good bone quality, mild/moderate deformity, and no predictors of poor postoperative pain coping, what strong argument exists against attempting cementless TKA? One may be able to point to the observation that cementless components tend to migrate more in the first 3 months to 2 years, but cemented components do so as well, sometimes even to a greater extent7. It is true that several important questions remain: what happens to the current RCT data at intermediate and long-term milestones? Are implant revisions easier with one type of fixation versus the other? Does fixation survival differ in mechanically versus kinematically aligned TKA? Is there an optimal porous surface coverage and keel/stem length that stands above other designs? Evidently, it will take more high-quality studies to answer all of these questions, but that should not necessarily stop surgeons from being selective in their clinical decisions. For now, it is clear that cement is certainly here to stay in primary TKA, especially in older, osteoporotic patients. However, we appear to be headed to what has already happened in hip arthroplasty—a recognition that a one-method-fits-all approach does not work for every patient. I congratulate the authors in helping us get one step closer to this reality.

Shoulder joint arthroplasty in young patients: Analysis of 8742 patients from the Australian Orthopaedic Association National Joint Replacement Registry.

Shoulder replacement is a reliable treatment for the relief of pain and improvement of function in patients with glenohumeral arthritis, rotator cuff arthropathy, osteonecrosis and fracture. Limited data is available comparing revision rates for the different types of shoulder replacement when used in younger patients. This study aims to compare the survivorship of hemi resurfacing, stemmed hemiarthroplasty, total shoulder arthroplasty and reverse total shoulder arthroplasty in younger patients using data from a large national arthroplasty registry. Data from theAustralianOrthopaedic AssociationNationalJoint ReplacementRegistry was obtained for the period 16 April 2004-31 December 2018. The study population included all shoulder arthroplasty patients aged <65 years. These were stratified into two groups: <55 years and 55-64 years. A total of 8742 primary shoulder arthroplasty procedures were analysed (1936 procedures in the <55 years and 6806 in the 55-64 years age group). In the <55 years age group, there was no difference in revision rate for total shoulder arthroplasty versus reverse total shoulder arthroplasty at any time point. Reverse total shoulder arthroplasty had a lower revision rate after six months when compared to hemi resurfacing (HRA) (p = 0.031). Also, reverse total shoulder arthroplasty had a higher early rate of revision in the first 12 months compared to hemiarthroplasty (p = 0.018). However, from 2 years reverse total shoulder arthroplasty had a lower revision rate overall (p = 0.029).In the 55-64 years patient age group, reverse total shoulder arthroplasty had a lower earlier revision rate. This was statistically significant compared to hemi resurfacing (HRA) (p = 0.028), hemiarthroplasty (p = 0.049) and total shoulder arthroplasty (p < 0.001). This study demonstrated that for patients aged <55 years there was no significant difference in the rate of revision when total shoulder arthroplasty and reverse total shoulder arthroplasty were compared. reverse total shoulder arthroplasty had a lower rate of revision when compared to hemi resurfacing and hemiarthroplasty after 2 years. reverse total shoulder arthroplasty had the lowest comparative revision rate in patients aged 55-64 years overall.

The burden of end-stage osteoarthritis in Australia: a population-based study on the incidence of total knee replacement attributable to overweight/obesity

To determine the risk of total knee replacement (TKR) for primary osteoarthritis (OA) associated with overweight/obesity in the Australian population. This population-based study analyzed 191,723 cases of TKR collected by the Australian Orthopaedic Association National Joint Registry and population data from the Australian Bureau of Statistics. The time-trend change in incidence of TKR relating to BMI was assessed between 2015 and 2018. The influence of obesity on the incidence of TKR in different age and gender groups was determined. The population attributable fraction (PAF) was then calculated to estimate the effect of obesity reduction on TKR incidence. The greatest increase in incidence of TKR was seen in patients from obese class III. The incidence rate ratio for having a TKR for obesity class III was 28.683at those aged 18-54 years but was 2.029at those aged >75 years. Females in obesity class III were 1.7 times more likely to undergo TKR compared to similarly classified males. The PAFs of TKR associated with overweight or obesity was 35%, estimating 14,287 cases of TKR attributable to obesity in 2018. The proportion of TKRs could be reduced by 20% if overweight and obese population move down one category. Obesity has resulted in a significant increase in the incidence of TKR in the youngest population in Australia. The impact of obesity is greatest in the young and the female population. Effective strategies to reduce the national obese population could potentially reduce 35% of the TKR, with over 10,000 cases being avoided.

Stainless Steel Femoral Heads Reduce Rate of Revision When Compared to Ion-Implanted Chromium-Cobalt Heads With a Single Cemented Femoral Design: An Analysis of 40,468 Total Hip Replacements From the Australian Orthopedic Association National Joint Replacement Registry.

In order to reduce the incidence of total hip joint replacement revision for wear, multiple advanced materials and alloys targeting hip replacement tribology have been introduced. Ion implantation of chromium-cobalt heads is thought to reduce wear due to increased surface hardness and lower friction. These advances in technology result in additional manufacturing costs. However, it is unclear whether these attributes result in a decreased rate of revision for wear and when used with modern highly crosslinked polyethylene (XLPE). The aim of this study is to compare the survivorship of stainless steel and ion-implanted chromium-cobalt femoral heads in order to determine whether ion implantation has a lower risk of revision. Data from the Australian Orthopedic Association National Joint Replacement Registry included all stainless steel and low-friction ion-treated (LFIT) femoral heads used in conjunction with a primary Exeter/Trident hip replacement combination and XLPE liners performed for osteoarthritis. Kaplan-Meier estimates of survivorship were used to describe the time to first revision. Hazard ratios (HRs) from Cox proportional hazard models, with adjustment for age and gender, were used to compare revision rates between the 2 groups. There were 40,468 total hip replacements that met the inclusion criteria. Stainless steel heads had a lower revision rate compared to LFIT chromium-cobalt heads (HR 0.87, 95% confidence interval 0.76-1.00, P= .048). The difference in the rate of revision was even greater when 32-mm heads were used (HR 0.72, 95% confidence interval 0.58-0.89, P= .002). There was no difference in revision for loosening between head alloys or when stratified by age. Given the increased costs associated with LFIT implants and the lower rate of revision for stainless steel heads, we recommend the use of a stainless steel heads when using an Exeter/Trident hybrid hip with an XLPE liner.

Best option for total hip replacement in young: evidence from National Joint Registry of United Kingdom and Australian Orthopaedic Association National Joint replacement Registry

Introduction&#x0D; &#x0D; Implant longevity is crucial in determining the clinical success of THA. Hence THA in young patients will need a careful consideration as the failure and revision rates of THA are higher due to high functional demands. &#x0D; &#x0D; Method&#x0D; &#x0D; Reviewed the latest evidence from the 17th annual report of National Joint Registry (NJR) of United Kingdom and the 2020 annual report of Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) to determine the optimal mode of fixation, bearing surface and the head size for THA in a patient before the age of 55 years.&#x0D; &#x0D; Results &#x0D; &#x0D; In THA of patients under 55 Years, the 10 Year RR was highest in Uncemented fixations compared to other modes but this difference is insignificant according to the AOANJRR. Uncemented and hybrid fixations were preferred over cemented fixations but uncemented was clearly the predominant mode of fixation and this preference was rising over the past years. COC and COP bearing surface combinations reported to have the lowest 10 YRR and the use of COP in young patients has been rising both in UK and Australia in the recent past. In COC the head size of 40mm showed the best survival rate and in COP 36mm was the largest size with better survival. In COP the increased quality with XLPE (ultra-high molecular weight polyethylene) has been the reason for the ability use a larger head size with low dislocation rates better survival with low wear compared to Non XLPE used in the past. &#x0D; &#x0D; Conclusion&#x0D; &#x0D; Both Registries favour the use of Uncemented or Hybrid fixations with COC and COP bearings in patients

The effect of polyethylene thickness on revision rates of contemporary cruciate retaining knee replacements. A registry analysis

BackgroundAn attribute that may influence knee replacement survivorship is tibial polyethylene (PE) insert thickness. Previous studies have suggested thin polyethylene made from ultra-high molecular weight polyethylene (UHMWPE) leads to higher rates of revision surgery. This study aimed to determine if modern polyethylene thickness is associated with altered survivorship of primary total knee arthroplasty (TKA) procedures. MethodsA retrospective analysis of data from Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) was done on well performing total knee arthroplasty prostheses used in Australia from 1999-2018. Six of the best performing minimally stabilized prostheses were examined and categorized into three PE thickness subgroups: A (≤10 mm), B (11–14 mm) and C (≥15 mm). There were 185,539 TKA procedures, of which 64.3% (n = 119,382) were ≤ 10 mm, 33.5% (n = 62,173) 11–14 mm, and 2.2% (n = 3984) ≥ 15 mm. Differences in revision rates were analysed for all causes, including loosening, wear, and instability. ResultsAt 14 years, respective cumulative point revision (CPR) was A: 4.8, B: 4.2 and C: 6.0. The thickest polyethylene group (≥15 mm) had a higher rate of revision for any reason compared to both 11–14 mm and ≤ 10 mm groups. When non-XLPE was analysed the ≤ 10 mm group had higher rates of revision compared to the 11–14 mm group, but this difference was not seen with XLPE. ConclusionHigher rates of revision were seen overall in the thicker PE group (≥15 mm). This group also had higher rates of revision for loosening, instability, and infection. The use of a thicker insert may be a sign of surgical complexity, but is associated with increased revision.

Assessing the suitability of general practice electronic health records for clinical prediction model development: a data quality assessment

BackgroundThe use of general practice electronic health records (EHRs) for research purposes is in its infancy in Australia. Given these data were collected for clinical purposes, questions remain around data quality and whether these data are suitable for use in prediction model development. In this study we assess the quality of data recorded in 201,462 patient EHRs from 483 Australian general practices to determine its usefulness in the development of a clinical prediction model for total knee replacement (TKR) surgery in patients with osteoarthritis (OA).MethodsVariables to be used in model development were assessed for completeness and plausibility. Accuracy for the outcome and competing risk were assessed through record level linkage with two gold standard national registries, Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and National Death Index (NDI). The validity of the EHR data was tested using participant characteristics from the 2014–15 Australian National Health Survey (NHS).ResultsThere were substantial missing data for body mass index and weight gain between early adulthood and middle age. TKR and death were recorded with good accuracy, however, year of TKR, year of death and side of TKR were poorly recorded. Patient characteristics recorded in the EHR were comparable to participant characteristics from the NHS, except for OA medication and metastatic solid tumour.ConclusionsIn this study, data relating to the outcome, competing risk and two predictors were unfit for prediction model development. This study highlights the need for more accurate and complete recording of patient data within EHRs if these data are to be used to develop clinical prediction models. Data linkage with other gold standard data sets/registries may in the meantime help overcome some of the current data quality challenges in general practice EHRs when developing prediction models.

Association between circulating 25-hydroxyvitamin D concentrations and hip replacement for osteoarthritis: a prospective cohort study

BackgroundTo examine the association between circulating 25(OH)D concentrations and incidence of total hip replacement for osteoarthritis in a prospective cohort study.MethodsThis study examined a random sample of 2651 participants in the Melbourne Collaborative Cohort Study who had 25(OH)D concentrations measured from dried blood spots collected in 1990-1994. Participants who underwent total hip replacement for osteoarthritis between January 2001 and December 2018 were identified by linking the cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. Cox proportional hazard regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) of total hip replacement for osteoarthritis in relation to 25(OH)D concentrations, adjusted for confounders.ResultsEighty-six men and eighty-seven women had a total hip replacement for osteoarthritis. Compared with men in the lowest (1st) quartile of 25(OH)D concentration, the HR for total hip replacement was 2.32 (95% CI 1.05, 5.13) for those in the 2nd quartile, 2.77 (95% CI 1.28, 6.00) for those in the 3rd quartile, and 1.73 (95% CI 0.75, 4.02) for those in the highest quartile of 25(OH)D concentrations (p for trend 0.02). There was little evidence of an association in women.ConclusionsHigher circulating 25(OH)D concentrations were associated with an increased risk of total hip replacement for osteoarthritis in men but not in women. Although the underlying mechanism warrants further investigation, our findings highlight the need to determine the optimal levels of circulating 25(OH)D to reduce the risk of hip osteoarthritis.