EMG, functional and postural responses to a physical therapy treatment for patellofemoral syndrome

Abstract

Patellofemoral Syndrome (PFS), a challenging pathology to treat – wherein full pain relief is rarely obtained – results from force imbalance exerted on the patella during its normal movement. This study assessed the effect of a physical therapy treatment on six 18-to-35 year-old subjects with PFS, diagnosed by the University Hospital Orthopedic Outpatient Clinic; five healthy subjects having the same age and level of physical activity as the patients made up the control group. Both groups were submitted to assessment before and after PFS group treatment: of pain through the visual analogical scale; of the patellofemoral joint according to Karlsson; Lysholm scale) lower limb postural alignment; patellar compression test; and electromyography of the vastus medialis and vastus lateralis muscles. PFS group treatment consisted in muscle stretching and strengthening exercises during 5 weeks, after which we observed a 50% reduction in positive signs of patellar compression, better Lysholm and Karlsson scores, lower plantar arches and reduction of valgus ankle; however, no pain relief was reported. Electromyographic data showed higher efficiency of the vastus medialis muscle in carrying out eccentric exercises and increased activity of the vastus lateralis while walking and during upward movement after squatting.