Table 3.

Studies investigating the usefulness of continuous passive motion after total knee replacement

Ref.	Type of study	Outcome
Maniar et al[35]	Prospective randomized trial. To use or not to use continuous passive motion post TKR	No benefit from CPM use in immediate functional recovery post-TKR and postoperative ROM. The postoperative knee swelling persisted longer in the CPM group
He et al[34]	Meta-analysis of randomized trials (Cochrane). CPM or not against VTE	No evidence that CPM reduces VTE after TKR
Harvey et al[33]	Meta-analysis of randomized trials (Cohrane). CPM use or not	CPM increases passive knee flexion ROM by mean 2 degrees and active knee flexion ROM by mean 3 degrees. This effect is too small to clinically justify the use of CPM. Weak evidence that CPM reduces the need for manipulation under anesthesia
Alkire et al[32]	Prospective randomized study. CPM use or not for computer-assisted TKA	No statistically significant difference in flexion, edema or drainage, function, or pain between groups 3 mo post-surgery
Lensenn et al[31]	Randomised controlled trial. Effectiveness of prolonged CPM use vs in hospital only use of CPM	No long term difference in ROM or any of the outcome assessments
Leach et al[29]	Prospective randomized trial investigating the effect of CPM on range of knee flexion, lack of extension, pain levels and analgesic use after TKR	No differences among studied groups
Brosseau et al[28]	Meta-analysis of studies examining the effectiveness of CPM	Significant improvement in active knee flexion and analgesic use 2 wk postoperatively with the use of CPM and PT compared with PT alone

CPM: Continuous passive motion; VTE: Venous thromboembolism; PT: Physiotherapy; TKR: Total Knee replacement; ROM: Range of motion.