Effectiveness of Exercise Therapy in Treatment of Patients With Patellofemoral Pain Syndrome: Systematic Review and Meta-Analysis

Background and Purpose. This systematic review and meta-analysis was accomplished to determine whether exercise therapy is an effective intervention to reduce pain and patient-reported measures of activity limitations and participation restrictions (PRMALP) in patients with patellofemoral pain. Data Sources and Study Selection. Randomized controlled trials in English and German languages published in the MEDLINE, Physiotherapy Evidence Database (PEDro), International Clinical Trials Registry Platform, and Cochrane databases were searched. Eligibility was assessed in 2 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 visual analog scale scores. Significance was set at 5%. Data Extraction and Data Synthesis. Fifteen studies, with a total of 748 participants, were included and pooled for the meta-analysis. Six studies compared the effect of exercise therapy with a control group receiving neither exercise therapy nor another intervention. Four studies compared the effect of exercise therapy versus additive therapy, and 5 studies 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, whereas long-term effects (>= 26 weeks) were observed for PRMALP only. Limitations and Conclusion. The 15 studies included in this analysis were of variable quality. Large-scale, high-quality randomized controlled trials are needed to further the evaluation of the possible effects of different exercise therapy modalities on patellofemoral pain. This meta-analysis presents evidence that exercise therapy has a strong pain-reducing effect and decreases PRMALP in patients with patellofemoral pain. However, the question of which exercise modality yields the strongest reducing effect on pain and PRMALP remains unanswered.