Comparison of Protonics^™ Knee Brace with Sport Cord on Knee Pain and Function in Patients with Patellofemoral Pain Syndrome: A Randomized Controlled Trial

Context: Protonics^™ knee brace has been suggested as an intervention for patients with patellofemoral pain syndrome. However, the effectiveness of this knee brace compared with traditional conservative methods knee rehabilitation is lacking. Objective: To compare the effect of Protonics^™ knee brace versus sport cord on knee pain and function in patients with patellofemoral pain syndrome. Design: Randomized controlled trial. Setting: Loma Linda University. Participants: There were 41 subjects with patellofemoral pain with a mean age of 28.8 (5.0) years and body mass index of 25.6 (4.7) kg/m² participated in the study. Intervention: Subjects were randomized to 1 of 2 treatment groups, the Protonics^™ knee brace (n = 21) or the sport cord (n = 20) to complete a series of resistance exercises over the course of 4 weeks. Main Outcome Measures: Both groups were evaluated according to the following clinical outcomes: anterior pelvic tilt, hip internal/external rotation, and iliotibial band flexibility. The following functional outcomes were also assessed: Global Rating of Change Scale, the Kujala score, the Numeric Pain Rating Scale, and the lateral step-down test. Results: Both groups showed significant improvement in the outcome measures. However, the Protonics^™ knee brace was more effective than the sport cord for the Global Rating of Change Scale over time (immediate 1.0 [2.1] vs post 2 wk 3.0 [2.2] vs 4 wk 4.6 [2.3] in the Protonics^™ brace compared with 0.0 [2.1] vs 1.3 [2.2] vs 3.0 [2.3] in the sport cord, P < .01), suggesting greater satisfaction. Conclusions: Both study groups had significant improvements in the clinical and functional symptoms of patellofemoral pain. The Protonics^™ knee brace group was significantly more satisfied with their outcome. However, the sport cord may be a more feasible and cost-effective method that yields similar results in patients with patellofemoral pain syndrome.