title: Effectiveness of exercise therapy in treatment of patients with patellofemoral pain syndrome: systematic review and meta-analysis.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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%.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: R. Clijsen, PhD, Department of Health Sciences, University of Applied Sciences and Arts of Southern Switzerland, Weststrasse 8, CH-7302 Landquart, Switzerland, and Health Department, University College Physiotherapy, "Thim van der Laan," Landquart, Switzerland. ron.clijsen@supsi.ch.
authors.forename: Ron
authors.initials: R
authors.lastname: Clijsen
authors.affiliation: J. Fuchs, PT, Health Department, University College Physiotherapy, "Thim van der Laan," Landquart, Switzerland.
authors.forename: Janine
authors.initials: J
authors.lastname: Fuchs
authors.affiliation: J. Taeymans, PhD, Health Department, Bern University of Applied Sciences, Bern, Switzerland.
authors.forename: Jan
authors.initials: J
authors.lastname: Taeymans
mesh_terms: D005081:Exercise Therapy; D006801:Humans; D053580:Muscle Strength; D046788:Patellofemoral Pain Syndrome / Q000503:physiopathology / Q000534:rehabilitation*; D052097:Quadriceps Muscle / Q000503:physiopathology; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome