Study Summary

Eleven randomized controlled trials comprising of 571 adults with patellofemoral pain were reviewed. Participants had a mean age ranging from 22 to 46 years, with interventions involving neuromuscular electrical stimulation (NMES) applied primarily to the quadriceps muscle was combined with structured exercise programs. This was compared with exercise alone or exercise with sham stimulation. Primary outcomes included pain intensity, knee joint function, and quadriceps muscle strength, while secondary outcomes assessed muscle activity, activity level, and participation. Outcomes were analyzed at short-term (<6 weeks) and long-term (≥6 weeks) treatment durations. Overall, the results demonstrated that NMES combined with exercise improved knee function and quadriceps strength in longer treatment courses, but did not provide additional benefit for pain relief, muscle activity, or participation compared with exercise alone. The certainty of evidence was rated as very low.