The Effect of Strengthening Exercises of the Hip Extensor and External Rotator Muscles on Patellofemoral Pain Syndrome

Abstract

Background: Patellofemoral pain syndrome (PFPS) is one of the most common knee disorders generally causing knee pain in active youth, particularly in runners. The main symptom of this complication is a gradual-onset vague pain in the anterior region of the knee and the posterior surface of the patella. In the current study, we aimed to assess the knee pain improvement following hip extensor and external rotator muscles’ strengthening exercises.

Methods: This randomized case-control clinical trial was conducted on 40 patients diagnosed with PFPS. The study group participated in the therapeutic strengthening exercise program for 8 weeks. The knee pain at rest, on running, stairs climbing, and during Scott exercise was measured at the beginning of the study and after completing the strengthening exercise.

Results: A total of 54 individuals were enrolled, out of which 14 were excluded due to insufficient patient data. The remaining 40 patients (all men) with the mean age of 26 ± 2 years were divided into two groups of 20 patients. The mean of the pain scores at the beginning of the study was 8.6 ± 0.8 and 8.2 ± 0.5 in the study group and the control group, respectively. The mean of pain scores decreased significantly to 6.0 ± 0.7 in the study group (P < 0.01). We had significant pain improvement on running, stairs climbing, and during Scott exercise following the strengthening exercise (P < 0.01).

Conclusion: Therapists can recommend this strengthening training program not only for the treatment of PFPS, but also for other knee disorders.