The effect of mobilization with movement on pain and function in patients with knee osteoarthritis: a randomized double-blind controlled trial

Background Few studies have investigated the effects of mobilization with movement (MWM) in patients with knee osteoarthritis (OA) compared to other procedures. Sham procedures are generally more appropriate control than using no or usual treatments. Moreover, studies investigating the widespread hypoalgesic effects of MWM in patients with knee OA are lacking. The aim was to investigate the effect of MWM on function and pain in patients with knee OA compared to sham MWM. Methods This is a randomized double-blind (patients and assessor) controlled trial. Forty adult patients with knee OA of grade II and above were recruited to receive either MWM treatment or sham MWM for the knee. The outcome measures included the following: a visual analogue scale (VAS) for pain, the pressure pain threshold (PPT) test, the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index, the timed up and go (TUG) test, knee strength and knee range of motion (ROM). The measurements were taken at baseline, immediately after intervention and 2 days later. Results Compared with sham MWM, MWM resulted in greater immediate improvement in pain [mean difference (95% CI): - 2.2 (- 2.8, - 1.6)], PPT at both the knee [176 (97, 254)] and shoulder [212 (136, 288)], TUG time [- 1.6 (- 2.1, - 1.1)], knee flexor strength [2.0 (1.3, 2.7)] and extensor strength [5.7 (4.1, 7.2)] and knee flexion ROM [12.8 (9.6, 15.9)] (all, p < 0.001) but not knee extension ROM [- 0.8 (- 1.6, 0.1)] (p = 0.067). After 2 days of intervention, patients who received MWM also demonstrated a greater improvement in pain [- 1.0 (- 1.8, - 0.1)], PPT at the shoulder [107 (40, 175)], TUG time [- 0.9 (- 1.4, - 0.4)], knee flexor strength [0.9 (0.2, 1.7)] and extensor strength [2.9 (2.1, 3.9)] and knee flexion ROM [8.3 (4.7, 11.9)] (all, p <= 0.026). However, WOMAC scores and knee extension ROM showed no evidence of change at any stage after intervention (p >= 0.067). Conclusions MWM provided superior benefits over sham MWM in terms of local and widespread pain, physical function (walking), knee flexion and extension muscle strength and knee flexion ROM for at least 2 days in patients with knee OA.