Efficacy of Graded Motor Imagery Compared to Conventional Physical Therapy in Treating Patients with Complex Regional Pain Syndrome

Introduction: Complex Regional Pain Syndrome (CRPS) is a chronic neurological pain syndrome characterized by allodynia, hyperalgesia, weakness, muscle spasms, skin color and temperature changes, and increased sweating. First line treatment usually consists of a combination pharmacotherapy and intensive physical therapy approach. However, this requires the patient to move their incredibly painful affected limb, which can further cause a pain flare and fear associated with movement. Graded motor imagery (GMI) is an emerging treatment that targets cortical structures using a non-pharmacological and non-invasive approach in which the patient does not need to move the affected limb. This paper will compare the effectiveness of GMI therapy to the conventional PT approach, in patients suffering from CRPS type I in one extremity, at improving function and reducing pain. Methods: A PubMed and EBSCOhost literature search was completed in November 2019. Ten articles were selected based on relevance to the study question. Two randomized controlled trials, 1 cohort study, 1 case series and 3 case reports were analyzed and compared. Results: The majority of the studies demonstrated a statistically significant reduction in pain and improvement in function, of the affected limb. Other positive findings include improved grip strength/active mobilization, perceived overall improvement of their condition and changes in brain activation on fMRI. Follow-up included in 4 of the studies found continued long-term improvement at 6 weeks to 2 years, depending on the study. The two RCT studies included compared the intervention group to a control group that continued to receive their ongoing medical treatment (drug therapy, PT, OT, CBT etc.). Results of case report studies gave insight into the positive effects of GMI in addressing the psychosocial aspects of CRPS treatment, such as fear associated with movement and trying new treatment plans. Discussion: Limited sample sizes, observational study designs, lack of a control group and inadequate follow up prevent findings from having the statistical power to be clinically significant. Nonetheless, significant positive findings were found in each of the articles using varying tools/questionnaires; and no study demonstrated negative health outcomes making GMI a minimal risk alternative. Conclusion: This review does not offer sufficient evidence to state that GMI is equally as or more effective than intensive PT at treating CRPS. The positive findings in these 7 articles suggest that future research is warranted and should be prioritized in reforming treatment guidelines for CRPS. While evidence-based recommendations cannot be made due to lack of power, providers may consider GMI therapy a simple, safe and cost effective alternative for patients who have failed other more conventional treatment options