Continuous passive motion compared to active physical therapy after knee arthroplasty: similar hospitalization times...

68 consecutive patients who had primary knee arthroplasties because of arthrosis were randomized to postoperative continuous passive motion (CPM) or active physical therapy (APT). Rehabilitation in both groups was initiated on the first postoperative day. The CPM group sustained less postoperative knee swelling with more rapid initial improvement in knee flexion than did the APT group, but there were no differences between the groups in knee flexion at discharge. Postoperative pain rating and hospitalization times were similar in the two groups.