Is there any advantage between using continuous passive motion and conventional physical therapy in patients with primary adhesive capsulitis?: A systematic review and meta-analysis.

Background: We are unsure if continuous passive motion (CPM) has any role in the nonoperative management of the Primary Stiff Shoulder (frozen shoulder). We hypothesized that there is no difference in pain improvement, range of motion, and function with or without CPM in patients with a primary stiff shoulder.

Method: We searched the databases for clinical trials comparing CPM versus no-CPM physiotherapy. In the final step, we reviewed five randomized clinical trials. We collected the data of Constant Shoulder Score (CSS), the visual analog scale of pain, shoulder pain and disability index (SPADI), and range of motion (flexion, abduction, external and internal rotation). We used a random-effects model to analyze the data.

Results: Five studies with a total of 224 patients were included. There were 113 patients in the CPM arm and 111 in the control arm. Both the CPM and control groups showed significant improvements in all measured parameters compared to the first visit after 8-24 weeks. Meta-analysis of pooled data showed significant differences in pain improvement, forward flexion, and CSS favoring the CPM. Still, there was no significant difference in abduction, external and internal rotation, and SPADI.

Discussion: The CPM seems to be slightly effective in improving pain and motion in the short term, but its long-term efficacy is still under question. The extra cost and time must be considered when offering the CPM.