The aim of the study was to identify the effectiveness of the continuous passive motion application on clinical outcomes after total knee arthroplasty, based on evidence from recently published high-quality randomized controlled trials.
Two reviewers retrieved platforms of PubMed, Embase, and CENTRAL independently, for identifying eligible randomized controlled trials evaluating the effect of continuous passive motion applied after total knee arthroplasty for knee osteoarthritis. Subgroup meta-analyses were performed for all syntheses based on the follow-up intervals.
A total of 10 randomized controlled trials, involving 841 patients, were finally included. Data were available for 15 different outcomes (including active/passive knee extension/flexion/full range of motion, Western Ontario and McMaster Universities Osteoarthritis Index-pain/physical function/stiffness/total score, visual analogue scale, time up and go, knee girth, Knee Society Scale-function/knee score), at several time points. In general, most of the pools demonstrated similar outcome between continuous passive motion and noncontinuous passive motion groups. Exclusively, the active knee extension at 1 wk (mean difference = 3.00, 95% confidence interval = 0.5-5.5, P = 0.019*), passive knee extension at 1 wk (mean difference = 3.00, 95% confidence interval = 0.28-5.72, P = 0.031*), and 3 mos (mean difference = 3.00, 95% confidence interval = 0.5-5.5, P = 0.019*) were shown to be significantly slightly different between two groups.
This study demonstrated a limited role of continuous passive motion in patients operated with total knee arthroplasty. Thus, there is at this stage no indication for continuous passive motion procedures in patients operated with total knee arthroplasty as a standard postoperative care.