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Published on: September 7, 2022
Baseline Characteristics Explain Sex Differences in Primary Total Knee Arthroplasty Outcomes: A Prospective
John M Bayram1, Swati Chopra2, Nicholas D Clement3
1School of Medicine, University of St Andrews, St Andrews, UK; Department of Orthopaedics, Golden Jubilee University National Hospital, Glasgow, UK; Edinburgh Orthopaedics, Royal Infirmary of Edinburgh, Edinburgh, UK.
Sex does not independently predict total knee arthroplasty outcomes. Women have worse preoperative profiles, but these differences disappear after adjusting for baseline factors, suggesting targeted interventions can improve TKA results.
Area of Science:
- Orthopedic Surgery
- Biomedical Engineering
- Rehabilitation Medicine
Background:
- Women report poorer outcomes after total knee arthroplasty (TKA).
- It is unclear if sex independently impacts TKA outcomes or if baseline differences explain disparities.
- This study investigated sex-based differences in TKA recovery over four years, controlling for confounding factors.
Purpose of the Study:
- To characterize sex differences in TKA outcomes over a four-year period.
- To determine if sex independently predicts TKA outcomes after adjusting for baseline characteristics.
- To identify potential targets for intervention to improve TKA outcomes for women.
Main Methods:
- Prospective multicenter cohort study of 229 patients undergoing primary TKA.
- Collection of patient-reported outcome measures (PROMs) and physical measures preoperatively and up to four years postoperatively.
- Analysis using linear mixed-effects models with unadjusted, demographic-adjusted, and baseline-adjusted models.
Main Results:
- Unadjusted analyses showed women had worse postoperative trajectories across most PROMs.
- Demographic adjustment attenuated some differences, but baseline adjustment eliminated all significant sex differences in PROMs.
- Women exhibited less favorable preoperative scores in pain, function, and mental health indicators.
Conclusions:
- Sex is not an independent predictor of TKA outcomes when baseline characteristics are considered.
- Women present with more significant preoperative deficits, including pain, functional limitations, and psychological factors.
- Optimizing preoperative status in women may reduce TKA outcome disparities.
