Additional Effects of an Individualized Risk Factor-Based Approach on Pain and the Function of Patients With Patellofemoral Pain Syndrome: A Randomized Controlled Trial

Objective: To investigate the clinical efficacy of adding risk factor-based approach (including appropriate exercises and orthoses) to routine quadriceps strengthening exercise with respect to pain and function in patients with patellofemoral pain syndrome (PFPS). Design: A parallel group nonblinded randomized controlled trial with 12-week follow-up. Setting: An outpatient Sports Medicine Clinic of Tehran University of Medical Sciences, Tehran, Iran. Participants: Patients (both sexes, 18-40 years) with clinically diagnosed PFPS of the duration over 2 months. Intervention: The intervention group received an individualized program, including exercise therapy plus risk factor modification, and was instructed to practice the tailored interventions at home for 12 weeks. The control group received an exercise program, only focusing on quadriceps strengthening. Main Outcome Measures: The primary outcomes were pain severity during the activities of daily living (0- to 100-point visual analog scale), and function (0- to 100-point Kujala patellofemoral score) at a 12-week follow-up. Results: A total of 53 participants completed the trial: 26 in the intervention and 27 in the control group. After 12 weeks, both groups showed improvements in pain and function, but the changes were significantly greater in the intervention group with regard to pain [adjusted difference, -14.90; 95% confidence interval (CI), -5.86 to -23.93, P = 0.002], and function (adjusted difference, 6.82; 95% CI, 2.54-11.10, P = 0.002). Conclusions: Assessment and modification of the risk factors may add to the treatment effects on pain and function at a 12-week follow-up in patients with PFPS. These findings may lead to a more comprehensive clinical approach to this very common problem.