The Effects of Exercise on Decreasing Pain and Increasing Function in Patients With Patellofemoral Pain Syndrome: A Systematic Review

Context: Exercise or rest is commonly prescribed as treatment for patellofemoral pain syndrome.Study Selection: This study is based on Level I or II research studies examining the effects of exercise and rest on decreasing pain (visual analog scale) and increasing function (Kujala Scoring Questionnaire) using human participants. Articles were limited to those printed in English from PubMed (1966-September 2010), CINAHL (1982-September 2010), and SPORTDiscus (1972-September 2010).Data Extraction: Weighted aggregate effect sizes and 95% confidence intervals were calculated from means and standard deviations extracted from 10 studies, resulting in an analysis of 433 patients.Results: A very large effect for exercise was found for patient-reported functional outcomes (d = 2.19) and perceived pain (d = -1.24) in treated patients, which were larger than functional outcomes (d = 0.77) and pain (d = -0.14) in controls. Short-term follow-up of 191 patients from 4 data sets in 2 studies revealed a large effect for functional outcomes (d = 1.04) and pain (d = -0.82) in patients who performed an exercise intervention. One study reported moderate effect sizes for functional outcomes (d = 0.59) and pain (d = -0.35) at 3 months postintervention.Conclusions: Exercise is the more effective treatment for immediate decrease in pain and increase in function although these differences appear to be less distinguishable over time.