Twenty-two primary total knee arthroplasties were prospectively randomized into one of two treatment protocols. Ten of these patients were managed in the hospital after surgery by means of a postoperative splint. The remaining 12 patients were placed immediately postoperatively in the recovery room into the continuous passive motion (CPM) device. The study compares the range of motion, analgesic use, hospital stay, and the volume of hemovac output in the two groups. These cases demonstrated two statistically significant findings with the use of CPM: (1) decreased use of narcotic analgesics and (2) decreased length of hospital stay.