Does electric stimulation of the vastus medialis muscle influence rehabilitation after total knee replacement?

Abstract

Patients with knee osteoarthritis present with reduced quadriceps muscle strength, which is partially responsible for impaired function and disability. Although total knee replacement (TKR) is an effective surgical procedure, residual muscle weakness is not usually addressed and may persist for years postoperatively. This article reports the results of a prospective, randomized, controlled trial evaluating the effect of electric muscle stimulation of the vastus medialis on the speed and effort of walking, quality of life, and knee performance in patients undergoing TKR. Seventy patients who underwent TKR were randomly divided into 2 groups. Patients in group A received electric muscle stimulation and standard physiotherapy for 6 weeks, while patients in group B received physiotherapy only. All patients were assessed with both subjective and objective clinical scales preoperatively and at 6, 12, and 52 weeks postoperatively. Patients in group A demonstrated a statistically significant increase in walking speed, Oxford Knee Score, and American Knee Society function score compared to those in group B at 6 weeks (P=.003, .001, and .001, respectively) and at 12 weeks (all P=.001). A statistically significant increase in the SF-36 physical component summary score was observed at 6, 12, and 52 weeks (all P=.001). Three patients found the sensation of the electrical stimulation uncomfortable and abandoned its use. No skin reactions and surgical site infections were observed. Electrical stimulation of the vastus medialis muscle in addition to conventional physiotherapy improves functional recovery and early rehabilitation after TKR.