INTRODUCTION: Patellofemoral pain syndrome (PPS) is characterized by diffuse pain in the retropatellar region, increased by daily tasks such as up and down stairs or kneeling. The PPS has a higher prevalence in young women and its etiology is not fully understood. OBJECTIVE: The purpose of this study was to assess the influence of different types of shoes on the patella stabilizer muscles during the tasks up and down stairs. MATERIALS AND METHODS: Ten healthy control women and ten women with patellofemoral pain syndrome (PPS) participated in this study. The subjects performed up and down stair tasks under three conditions; barefoot, with tennis shoes and 10 cm high heel shoes. Electromyographic (EMG) activity was recorded from vastus medialis oblique (VMO), vastus lateralis (VL) and Rectus femoris (RF) muscles during the tasks using surface differential electrodes connected to an EMG system. The intergroup comparison was realized using the unpaired test t and the intragroup using the repeated measures ANOVA post hoc Tukey, all with level of significance of 5%. RESULTS: Results demonstrated higher EMG activity for the VMO muscles during the eccentric and concentric phases performed with high heeled-shoes in the control group. However, in the PPS group, the VMO activity did not influence in any of the proposed conditions. There were no differences in VMO/VL ratio and onset timing for the both groups. CONCLUSION: The results suggest that in asymptomatic women using high-heeled shoes changed activity of all muscles. However, women with PFPS showed no changes in VMO.
Patellofemoral pain syndrome; Electromyography; Shoes
