145 patients who had undergone total knee arthroplasty and had poor postoperative knee range of motion were included in this study. Patients randomized to either a continuous passive motion group or control group for rehabilitation at an inpatient rehabilitation facility. Measures of range of motion (flexion and extension), functional outcome, walking ability, and length of stay were evaluated at discharge from the rehabilitation facility. Results demonstrated no significant differences in any outcome between groups, indicating no benefit of CPM use in postacute rehabilitation after TKA.