A Novel Mobile App-based Neuromuscular Electrical Stimulation Therapy for the Management of Knee Osteoarthritis: Results From an Extension Study of a Randomized, Double-blind, Sham-controlled, Multicenter Trial.

Background: Mobile app-based neuromuscular electrical stimulation (NMES) is a promising treatment of knee osteoarthritis as previously demonstrated in a 12-week, randomized, double-blind, sham-controlled, multicenter trial (parent study).

Methods: Sixty-four of the 253 patients with knee osteoarthrosis who completed the 12-week parent study were enrolled in a 14-week extension study during which they continued to receive double-blind, home-based NMES (two 20-minute daily sessions, 5 d/wk) with either the original device ("active NMES") or a low-voltage version ("sham NMES"). All subjects who enrolled in the extension study comprised the intent-to-treat population and subjects who applied NMES (compliance monitored through the mobile app and a remote portal) for at least 2,800 minutes (14-week device usage) comprised the per-protocol therapy compliant population.

Results: In the per-protocol therapy compliant population, the active NMES group (n = 21) had a higher reduction in Visual Analog Scale Nominated Activity (64.7% versus 24.3%, P = 0.020) and Visual Analog Scale Nominated Activity improvement ≥50% (76.2% versus 12.5%, P = 0.002) than the sham NMES group (n = 8). Outcomes were not markedly different between groups in the intent-to-treat population.

Discussion: Applying NMES therapy for an additional 14 weeks (totaling 26 weeks) resulted in notable and clinically meaningful pain relief when patients were fully compliant with NMES.