Document Type : Research Paper


1 Associate Professor, Department of Rheumatology, University of Medical Sciences

2 Associate Professor, Department of Health and Sport Medicine, School of Physical Education, University of Tehran

3 Professor, Department of Health and Sport Medicine, School of Physical Education, University of Tehran


The purpose of this study was to compare the effects of three exercise therapy protocols on pain, muscle strength and function for patellofemoral pain syndrome. 41 women with patellofemoral pain syndrome were randomly assigned to the intervention groups and control group. All intervention groups participated in an eight-week exercise protocol. Pain, knee extensors, hip abductors and external rotators strength and function of patients were assessed before and after the intervention. According to repeated measure ANOVA all intervention groups showed significant improvement in pain, muscle strength and function. There weren’t significant improvements in quadriceps strength and function in the hip group. The observed improvements in pain scale in the three exercise groups were maintained at a 6-month follow-up. Rehabilitation programs focusing on knee strengthening exercises and knee-hip strengthening exercises were both effective in improving function and reducing pain in women with patellofemoral pain syndrome.


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