Radiological and Electromyographic Evaluation in Patellofemoral Pain Syndrome

Abstract

Objective: This study aims to investigate the electrical activity of the muscles vastus medialis oblique (VMO) and vastus lateralis (VL) and patellar alignment in subjects with PFPS. Methods: It was carried out a physical and electromyographic evaluation of 20 patients affected by the syndrome and 8 sedentary non-affected ones. Electromyography was performed using a biofeedback device with two channels, one in the VMO and another in the VL. There were three isometric contractions in each knee at angles of 120º and 180º, with duration of ten seconds and rest for thirty seconds. The lateralization of the patella was measured by X-rays by the Method of Bilateral Merchant. Results: There was no significant difference in the VMO / VL for both clinically healthy subjects and for people with PFPS at the different angles of contraction. The radiological analysis showed lower values than the mean values suggested in the literature for the Angle of the Sulcus, Angle of Congruence and Angle of Patellar Inclination. Conclusion: According to the experimental conditions, it was found that healthy subjects and those with PFPS showed a relationship VMO / VL similar regarding isometric contractions at angles of 120° and 180°. The radiographic evaluation in this study showed results different from those of the literature. DESCRIPTORS Patellofemoral Pain Syndrome. Biofeedback. Electromyography.