Effect of Therapeutic Modalities on Patients With Patellofemoral Pain Syndrome: A Systematic Review

CONTEXT: Patellofemoral pain syndrome (PFPS) is a common orthopaedic condition for which operative and nonoperative treatments have been used. Therapeutic modalities have been recommended for the treatment of patients with PFPS—including cold, ultrasound, phonophoresis, iontophoresis, neuromuscular electrical stimulation, electrical stimulation for pain control, electromyographic biofeedback, and laser. OBJECTIVE: To determine the effectiveness of therapeutic modalities for the treatment of patients with PFPS. DATA SOURCES: In May and August 2010, Medline was searched using the following databases: PubMed, CINAHL, Web of Science Citation Index, Science Direct, ProQuest Nursing & Allied Health, and Your Journals@OVID. STUDY SELECTION: Selected studies were randomized controlled trials that used a therapeutic modality to treat patients with PFPS. The review included articles with all outcome measures relevant for the PFPS patient: knee extension and flexion strength (isokinetic and isometric), patellofemoral pain assessment during activities of daily life, functional tests (eg, squats), Kujala patellofemoral score, and electromyographic recording from knee flexors and extensors and quadriceps femoris cross-sectional areas. DATA EXTRACTION: Authors conducted independent quality appraisals of studies using the PEDro Scale and a system designed for analysis of studies on interventions for patellofemoral pain. RESULTS: Twelve studies met criteria: 1 on the effects of cold and ultrasound together, ice alone, iontophoresis, and phonophoresis; 3, neuromuscular electrical stimulation; 4, electromyographic biofeedback; 3, electrical stimulation for control of pain; and 1, laser. DISCUSSION: Most studies were of low to moderate quality. Some reported that therapeutic modalities, when combined with other treatments, may be of some benefit for pain management or other symptoms. There was no consistent evidence of any beneficial effect when a therapeutic modality was used alone. Studies did not consistently provide added benefit to conventional physical therapy in the treatment of PFPS. CONCLUSIONS: None of the therapeutic modalities reviewed has sound scientific justification for the treatment of PFPS when used alone.