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Background: Polished baseplates were introduced into total knee arthroplasty (TKA) systems to reduce the incidence of backside wear. In 2004, a fixed-bearing knee arthroplasty system underwent a change in baseplate material from matt titanium to polished cobalt-chrome (CoCr) with the intention to reduce backside wear. Other design aspects were left unchanged. The aim of this study was to compare these implants with each baseplate using data from the Australian Orthopaedic Association National Joint Replacement Registry., Methods: Primary TKA procedures performed between January 2010 and December 2021 for osteoarthritis, using a single design with cross-linked polyethylene inserts and matt titanium or polished CoCr baseplates, were analyzed. The primary outcome was all-cause revision, summarized using Kaplan-Meier estimates, with age- and sex-adjusted hazard ratios estimated from Cox proportional hazards models. In total, there were 2,091 procedures with matt titanium and 2,519 procedures with polished CoCr baseplates., Results: The 9-year cumulative percent revision was 2.5% (95% confidence interval [CI] 1.8 to 3.5%) and 4.2% (95% CI 3.1 to 5.6%) for the matt titanium and CoCr groups, respectively. Compared to matt titanium, the revision rate of CoCr baseplates was not significantly higher (hazard ratio 1.44; 95% CI 0.96 to 2.15; P = .076)., Conclusions: Polished CoCr baseplates in a single TKA system were not associated with reduced all-cause revision rates compared to matt titanium up to 11 years post-TKA. Our results suggest that the predicted reduction in wear particle debris production from polished CoCr baseplates may not correlate with reduced revision rates in vivo, but further evaluation is required., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Importance: Despite the increasing number of tools available to predict the outcomes of total knee arthroplasty (TKA), the effect of these predictive tools on patient decision-making remains uncertain., Objective: To assess the effect of an online predictive tool on patient-reported willingness to undergo TKA., Design, Setting, and Participants: This parallel, double-masked, 2-arm randomized clinical trial compared predictive tool use with treatment as usual (TAU). The study was conducted between June 30, 2022, and July 31, 2023. Participants were followed up for 6 months after enrollment. Participants were recruited from a major Australian private health insurance company and from the surgical waiting list for publicly funded TKA at a tertiary hospital. Eligible participants had unilateral knee osteoarthritis, were contemplating TKA, and had previously tried nonsurgical interventions, such as lifestyle modifications, physiotherapy, and pain medications., Intervention: The intervention group was provided access to an online predictive tool at the beginning of the study. This tool offered information regarding the likelihood of improvement in quality of life if patients chose to undergo TKA. The predictions were based on the patient's age, sex, and baseline symptoms. Conversely, the control group received TAU without access to the predictive tool., Main Outcomes and Measures: The primary outcome measure was the reduction in participants' willingness to undergo surgery at 6 months after tool use as measured by binomial logistic regression. Secondary outcome measures included participant treatment preference and the quality of their decision-making process as measured by the Knee Decision Quality Instrument., Results: Of 211 randomized participants (mean [SD] age, 65.8 [8.3] years; 118 female [55.9%]), 105 were allocated to the predictive tool group and 106 to the TAU group. After adjusting for baseline differences in willingness for surgery, the predictive tool did not significantly reduce the primary outcome of willingness for surgery at 6 months (adjusted odds ratio, 0.85; 95% CI, 0.42-1.71; P = .64)., Conclusions and Relevance: Despite the absence of treatment effect on willingness for TKA, predictive tools might still enhance health outcomes of patients with knee osteoarthritis. Additional research is needed to optimize the design and implementation of predictive tools, address limitations, and fully understand their effect on the decision-making process in TKA., Trial Registration: ANZCTR.org.au Identifier: ACTRN12622000072718.

Background: Patient-reported outcome measure (PROM) questionnaires in national arthroplasty registries often have low response rates leading to questions about data reliability. In Australia, the SMART (St. Vincent's Melbourne Arthroplasty Outcomes) registry captures all elective total hip (THA) and total knee (TKA) arthroplasty patients with an approximate 98% response rate for preoperative and 12-month PROM scores. This high response rate is due to dedicated registry staff following up patients who do not initially respond (subsequent responders). This study compared initial responders to subsequent responders to find differences in 12-month PROM outcomes for THA and TKA., Methods: All elective THA and TKA patients for osteoarthritis from 2012 to 2021 captured by the SMART registry were included. In total, 1,333 THA and 1,340 TKA patients were included. The PROM scores were assessed using the Veterans-RAND 12 (VR12) and Western Ontario and McMasters Universities Arthritis Index (WOMAC) questionnaires. The primary outcome was differences in mean 12-month PROM scores between initial and subsequent responders., Results: Baseline characteristics and PROM scores were similar between initial and subsequent responders. However, 12-month PROM scores varied significantly. The adjusted mean difference showed that for the WOMAC pain score, subsequent responders scored 3.4 points higher in the THA cohort and 7.4 points higher in the TKA cohort compared to initial responders. Significant differences were also found in other WOMAC and VR12 scores for both THA and TKA cohorts at the 12-month timepoint., Conclusion: This study found that significant differences in PROM outcomes postsurgery occurred in THA and TKA patients based on response to PROM questionnaires, suggesting that loss to follow-up in PROM outcomes should not be treated as missing completely at random (MCAR)., (Copyright © 2023 Elsevier Inc. All rights reserved.)