Physical Functioning and Prediction of Physical Activity After Total Hip Arthroplasty: Five-Year Followup of a Randomized Controlled Trial

Objective. To examine whether the 1-year effects from a previous walking skill training program on walking and stair climbing still persist 5 years following total hip arthroplasty (THA), to examine recovery of physical functioning from before to 5 years after surgery, and to identify predictors of physical activity 5 years after THA from preoperative measures. Methods. We performed a 5-year followup of a randomized controlled trial and a longitudinal study. Sixty participants with a mean age of 70 years (range 50-87 years; 95% confidence interval 68, 72 years) were assessed. Outcome measures were the 6-minute walk test, the stair climbing test (SCT), active hip range of motion (ROM), self-efficacy, Hip Dysfunction and Osteoarthritis Outcome Score (HOOS), and University of California, Los Angeles (UCLA) activity scale. Data were analyzed by Student's t-tests, generalized linear model, and multivariate regression analyses. Results. The training and control groups were approximately equal on outcome measures of physical functioning, pain, and self-efficacy at 5 years (P > 0.05). In the total group, the recovery course was unchanged from 1 to 5 years (P > 0.05), except for 9% improvement in ROM (P < 0.001) and an increase in time on SCT of 18% (P = 0.004). Preoperative HOOS pain (P = 0.022) and HOOS sport (P = 0.019) predicted UCLA activity scale 5 years after THA. Conclusion. At 5 years after THA, the control group had caught up with the training group on physical functioning, and the participants led an active lifestyle. Those with worse preoperative scores on pain and physical functioning in sport were at risk of being less physically active in the long term following THA.