Continuous passive motion on pain management in patients with total knee arthroplasty

Continuous passive motion (CPM) has found increasing popularity in rehabilitation of patients undergoing total knee arthroplasty (TKA) over the past decade. However, there is still controversy about its benefits on pain. The objective of this study was to determine whether patients undergoing TKA benefit from CPM. Thirty-two female patients who underwent primary TKA due to degenerative osteoarthritis were included in the study. They were divided into two similar groups (CPM group and non-CPM group). Both groups followed the same postoperative rehabilitation program. Sixteen patients received additional CPM therapy according to a defined protocol for 3 weeks after surgery. All patients were evaluated for pain intensity by VAS and by 'The Knee Society Scoring System' before the treatment, after the treatment, and after the follow-up. Patients were hospitalized for three weeks. The follow-up lasted 3 months. The results showed that the standardized postoperative rehabilitation program relived the pain in both groups. There were no significant differences between the groups, although the patients of the CPM group showed slightly lower pain intensity than those in the non-CPM group. It can be concluded that CPM in TKA patients has no clinical importance for pain relief in postoperative rehabilitation.