Optimizing Total Knee Arthroplasty Rehabilitation With Telehealth Physical Activity Behavior Change Intervention: A Randomized Clinical Trial.

Objective: Conventional total knee arthroplasty (TKA) rehabilitation has little impact on sedentary lifestyles that have negative long-term health consequences. The purpose of this trial was to determine the effect of telehealth-based physical activity behavior change intervention on physical activity and functional outcomes following TKA.

Methods: This study was a 2-arm, parallel randomized controlled superiority trial at a regional Veterans Affairs medical center. The participants were 92 US military veterans (mean age = 65.7 [SD =7.8] y) undergoing unilateral TKA. The Physical Activity Behavior Change (PABC) intervention included telehealth-based self-management training (10 30-minute sessions) delivered over 12 weeks. The control intervention included telehealth-based health education sessions that matched PABC frequency and duration. Both groups participated in standardized conventional outpatient rehabilitation. Physical activity, measured as average daily step count, was the primary outcome. Secondary outcomes were Life-Space Assessment questionnaire, 30-Second Chair-Stand test, Timed "Up & Go" Test, 6-Minute Walk Test, Western Ontario and McMaster Universities Osteoarthritis Index, and Veterans RAND 12-Item Health Survey. The Self Efficacy for Exercise scale and daily time spent in different postures (sitting/lying, standing, stepping) were exploratory variables. Outcomes were measured at baseline (before surgery), mid-intervention (8 weeks after surgery), after the intervention (14 weeks after surgery; primary endpoint), and follow-up (38 weeks after surgery).

Results: The PABC group had an estimated 931 (95% CI = 42-1819) more daily steps than the control group from baseline to 14 weeks, though a between-group effect was not sustained at 38 weeks. There were no group differences in secondary outcomes. Participants included only military veterans using Veterans Health Administration services. The intervention targeted self-management and did not include peer support.

Conclusion: The PABC intervention improved physical activity for veterans recovering from unilateral TKA at 14 weeks after surgery, though the effect was not sustained at 38 weeks. Physical function improved with rehabilitation but was not different between groups, indicating that physical function was not a primary driver of physical activity behavior.

Impact: Conventional TKA rehabilitation has a negligible effect on free-living physical activity, which is relevant to long-term health outcomes. This trial identified telehealth physical activity self-management as effective in addressing activity behaviors, separate from conventional rehabilitation strategies.