Background Continuous passive motion (CPM) is a common procedure in total knee replacement (TKR), but its effectiveness is controversial at early stage after TKR. Some studies have claimed that CPM promoting rapid postoperative recovery and the range of motion (ROM). However, some studies have demonstrated that CPM have any benefit on ROM, length stay of hospital and postoperative recovery (1, 2). Several studies have examined the use of CPM, but there is not any study that compared the effect of repetitive active range of motion (AROM) vs. CPM on early functional outcomes after TKR.
Objectives The aim of this study was to compare the effect of AROM vs. CPM on early functional outcomes after TKR.
Methods The study group consisted of 71 patients, who underwent primary TKR because of arthrosis were consecutively allocated to a AROM group (n=40, with median age; 70.8±7.9 years), and were allocated to a CPM group (n=31, with median age; 69.7±8.4 years). Patients were evaluated regarding knee function score (Hospital for Special Surgery (HSS) score), pain (Numeric Pain Rating Scale (NPRS)), knee circumference, knee range of motion, length of hospital stay, the day of knee flexion angle achieved 70 degrees and quality of life (Short-Form 12 Health Survey (SF-12). Functional activities were evaluated using the Iowa Level of Assistance Scale and walking speed was evaluated using the Iowa Ambulation Velocity Scale. Also functional outcomes were evaluated with timed up and go (TUG) test and 10-meter walk test (10 MWT). Patients were evaluated preoperatively and at discharge.
Results At baseline, demographic and anthropometric characteristics were similar in groups and there was no statistically difference between groups (p>0.05). It was determined that; the AROM group had better results in terms of reduction of pain severity (p<0.001). When the HSS knee scores were compared there was statistically difference between groups (p<0.001) and the HSS knee scores were lower in CPM group after surgery. There were no statistical differences in knee circumference, knee range of motion, the day of achieved active straight leg raise, length of hospital stay, the day of knee flexion angle achieved 70 degrees, quality of life, the IOWA help level score, IOWA walking speed score, 10 MWT score and TUG test score between groups after TKR (p>0.05).
Conclusions In patients with TKR, application of repetitive AROM has better results than CPM to decrease pain severity, improve the HSS knee score. However, AROM has no effect on the early functional outcomes and the other early patients' outcomes. The current results suggest that application of AROM might be an effective method to decrease pain severity, improve the HSS knee score.
Maniar RN, Baviskar JV, Singhi T, et al. To use or not to use continuous passive motion post–total knee arthroplasty: Presenting functional assessment results in early recovery. The Journal of Arthroplasty. 2012;27(2),193–200.
Bruun-Olsen V, Heiberg KE, Mengshoel AM. Continuous passive motion as an adjunct to active exercises in early rehabilitation following total knee arthroplasty–a randomized controlled trial. Disability and Rehabilitation. 2009;31(4), 277–283.
Disclosure of Interest None declared