Especially in younger knee osteoarthritis patients, the ability to perform physical activity (PA) after knee arthroplasty (KA) is of paramount importance, given many patients' wish to return to work and perform demanding leisure time activities. Goal Attainment Scaling (GAS) rehabilitation after KA may improve PA because it uses individualized activity goals. Therefore, our aim was to objectively quantify PA changes after KA and to compare GAS-based rehabilitation to standard rehabilitation.
Data were obtained from the randomized controlled ACTION trial, which compares standard rehabilitation with GAS-based rehabilitation after total and unicompartmental KA in patients <65 years of age. At 2 time points, preoperatively and 6 months postoperatively, 120 KA patients wore a validated 3-dimensional accelerometer for 1 consecutive week. Data were classified as sedentary (lying, sitting), standing, and active (walking, cycling, running). Repeated measures analysis of variance was used to compare PA changes over time.
Complete data were obtained for 97 patients (58% female), with a mean age of 58 years (±4.8). For the total group, we observed a significant increase in PA of 9 minutes (±37) per day (P = .01) and significant decrease in sedentary time of 20 minutes (±79) per day (P = .02). There was no difference in standing time (P = .11). There was no difference between the control group and the intervention group regarding changes in PA, nor between the total KA group and the unicompartmental KA group.
We found a small but significant increase in overall PA after KA, but no difference between GAS-based rehabilitation and standard rehabilitation. Likely, enhanced multidisciplinary perioperative strategies are needed to further improve PA after KA.