Participation in regular physical activity after total knee or hip arthroplasty for osteoarthritis: prevalence, associated factors, and type.

OBJECTIVE: This study aimed to describe the: rates of participation in regular physical activity (PA) pre- and 3-years following knee or hip arthroplasty; factors associated with participation post-surgery; and types of activity undertaken.

METHODS: A previously acquired, multicentre, prospective cohort of knee or hip arthroplasty recipients was followed-up 3-years post-surgery. Regular participation in PA was defined as participation in PA ≥1 times/week, excluding incidental activities. Participants were interviewed about current participation as well as participation in the year pre-surgery. Joint-specific and health-related quality of life scores and experience of major complications were obtained. Co-morbid information and body weight were updated. Factors associated with 3-year PA participation were determined using multivariable logistic regression modelling.

RESULTS: 74% (1289/1773) of the eligible cohort were followed-up (718 knee, 571 hip). Participation profiles were similar regardless of joint replaced. Participation in PA increased post-surgery [combined cohort, 45.2 to 63.5%, P<0.001]. Participation at 3-years was associated with participation pre-surgery (P<0.0001), better 3-year quality of life (P<0.001), younger age (P=0.002), better 3-year joint scores (P= 0.01), > 1 lifetime arthroplasty (P=0.02), and higher education (P=0.04). Low-impact and non-ambulatory activities significantly increased post-surgery with no change in high-impact activities.

CONCLUSION: Participation rates increase post-surgery when recovery is stable, but approximately one-third of arthroplasty recipients do not engage in PA at least once per week. As participation is associated with habitual activity pre-surgery, a potential role for behaviour change interventions is suggested. That non-ambulatory activities increase indicates current devices measuring ambulatory activity alone are inadequate for capturing PA. This article is protected by copyright. All rights reserved.