Effects of whole-body vibration plus hip-knee muscle strengthening training on adult patellofemoral pain syndrome: a randomized controlled trial

PURPOSE To investigate whether whole-body vibration (WBV) plus hip-knee muscle strengthening is more efficient in relieving pain and improving function than hip-knee strengthening alone. METHODS Thirty-six participants with patellofemoral pain syndrome (PFPS) were recruited and randomly allocated to either the (1) hip-knee strengthening only (HK group, n = 18) or (2) WBV plus hip-knee strengthening group (WHK group, n = 18). All participants attended 18 physiotherapy sessions (3 sessions/week, 40 min/session) over 6 weeks. Data on symptoms, function, surface electromyography (sEMG) signals from the vastus medialis and gluteus medius, and quality of life were evaluated at baseline (T0), 6 weeks after (T6), and the 12-week follow-up (T18). RESULTS Significant group × time interactions were found for the VAS score (p < 0.001) and vastus medialis performance (p ≤ 0.015). The WHK group exhibited a greater pain relief than did the HK group at T18 (p ≤ 0.014). The WHK group exhibited significantly larger improvements in the RMS value than did the HK group at T6 (p ≤ 0.011). CONCLUSIONS The present study shows that 6 weeks of WBV plus hip-knee strengthening can improve vastus medialis performance and maintain long-term pain relief to a significantly greater extent than can hip-knee strengthening alone.IMPLICATIONS FOR REHABILITATIONThe present study shows that 6 weeks of WBV plus hip-knee strengthening can improve vastus medialis performance and maintain long-term pain relief to a significantly greater extent than can hip-knee strengthening alone.