Effect of a SERF Strap on Pain and Knee-Valgus Angle During Unilateral Squat and Step Landing in Patellofemoral Patients.

Context: A valgus position of the knee on functional loading tasks has been reported to be associated with patellofemoral-joint pain. Training programs to reduce knee valgus have been shown to be effective but take time. It would appear logical to use a brace or strap to help control this knee motion to reduce symptoms. Objective: To assess the impact of the SERF strap on knee valgus and patellofemoral-joint pain. Design: Repeated measures. Setting: University human performance laboratory. Participants: 12 women with patellofemoral pain (mean age 24 ± 3.2 y). Intervention: Application of SERF strap. Main Outcome Measures: Knee-valgus angle on single-leg squat and step landing and visual analog scale pain score. Results: The application of the SERF brace significantly reduced the pain (P < .04) and knee valgus (P < .034) during both tasks. Conclusion: The SERF brace brings about a significant reduction in pain during functional tasks. Although the brace brought about a significant reduction in knee valgus, this failed to exceed the smallest-detectable-difference value, so the difference is likely to be related to measurement error. The mechanism as to why this the reduction in pain occurs therefore remains unclear, as this study in line with many others failed to demonstrate meaningful changes in kinematics that could provide an obvious explanation. [ABSTRACT FROM AUTHOR]