Twenty randomised controlled trials of 1335 participants met the inclusion criteria. There is high-quality evidence that continuous passive motion increases passive knee flexion range of motion (mean difference 2 degrees, 95% CI 0 to 5) and active knee flexion range of motion (mean difference 3 degrees, 95% CI 0 to 6). These effects are too small to be clinically worthwhile. There is low-quality evidence that continuous passive motion has no effect on length of hospital stay (mean difference -0.3 days; 95% CI -0.9 to 0.2) but reduces the need for manipulation under anaesthesia (relative risk 0.15; 95% CI 0.03 to 0.70).
This summary of a Cochrane review presents what we know about the effect of continuous passive motion (CPM) as a treatment to improve range of motion and function after knee replacement surgery.
In people who had knee replacement surgery:
- Continuous passive motion improved their range of motion slightly;
- Continuous passive motion may not make any difference to how long they stayed in hospital;
- We often do not have precise information about side effects and complications. This is particularly true for rare but serious complications.
Range of motion – Active knee flexion
- People who did not have CPM were able to move their knee an average of 75 degrees
- People who did have CPM were able to move their knee 3 degrees more, an average of 78 degrees.
Range of motion – Passive knee Flexion
- People who did not have CPM were able to move their knee an average of 82 degrees
- People who did have CPM were able to move their knee 2 degrees more, an average of 84 degrees.
Length of Hospital Stay
- People who did not have CPM stayed in hospital an average of 13 days, about the same as people who did have CPM.
Bibliography:
Harvey LA, Brosseau L, Herbert RD. Continuous passive motion following total knee arthroplasty in people with arthritis. Cochrane Database of Systematic Reviews 2010, Issue 3. Art. No.: CD004260. DOI: 10.1002/14651858.CD004260.pub2
Online Link:
http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD004260.pub2/
abstract;jsessionid=E6DAD58B745F924E29EAEF961BCE64B5.d03t03