The effects of combining electrical stimulation of the calf and thigh muscles on WOMAC pain in knee osteoarthritis: A double-blind, randomised, sham-controlled trial

Objective

To explore the effectiveness of a NMES device in improving pain and function for individuals with KOA.

Method

This was a randomised, sham-controlled, superiority trial recruiting individuals with symptomatic KOA, with both participants and outcome assessors blinded to the treatment allocation. Participants were randomised to receive either self-administered NMES, consisting of quadriceps (5 times a week) and footplate stimulation (7 times a week), or a sham device for 8 weeks. The primary outcome was the change in Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain domain at week 8.

Results

179 participants were randomised; 50.8 ​% female, mean (SD) age 66.9 (8.7) years. 164 attended the follow up visit. No difference in the WOMAC pain domain was seen between groups (−0.7; 95 ​% CI: −1.5, 0.1; P ​= ​0.10), though within group improvements were reported in both groups (NMES: −1.5; 95 ​% CI: −2.0, 0.8; P ​< ​0.01, sham: −0.8; 95 ​% CI: −1.4, 0.2; P ​< ​0.01). There were no differences in strength, exercise and functional capacity, swelling, health related quality of life or anxiety and depression between groups. Sub-group analysis for NMES compliance or recruitment source did not change response in primary outcome.

Conclusion

Use of an NMES device on the quadriceps and plantar flexors did not enhance pain relief or improve function over the sham control in people with KOA.