This systematic review and meta-analysis was conducted to determine whether exercise therapy is an effective intervention to decrease pain and patient-reported measures of activity limitations and participation restrictions (PRMALP) in patients with patellofemoral pain. Randomized controlled trials in English and German language, published in Medline, PEDro and Cochrane databases were searched. Eligibility was assessed in two stages. The methodological quality of the studies was rated using the PEDro scale. Data were pooled using random-effects meta-analysis allowing for variability among studies. For clinical use, overall estimates were re-expressed in the original VAS scores. Significance was set at 5%. Fifteen studies with a total of 748 participants were included and pooled for a meta-analysis. Six studies compared the effect of exercise therapy with a control group neither receiving exercise therapy or any other intervention. Four studies compared the effect of exercise therapy versus additive therapy while five papers compared different exercise interventions. In both comparisons exercise therapy resulted in strong pain reduction and improvement of PRMALP effects. Significant short-term effects(≤12 weeks) of exercise therapy were found for pain and PRMALP while long -term effects (≥26 weeks) were seen for PRMALP only.
This meta-analysis offers evidence that exercise therapy has a strong pain reducing effect and reduces PRMALP in patients with patellofemoral pain. However, the question, which exercise modality results in the strongest reductive effect on pain and PRMALP, remains unrevealed. The 15 studies included in this analysis were of variable quality. Large, high quality RCTs are required to further the evaluation of the possible effects of different exercise therapy modalities on patellofemoral pain.