Effectiveness of Prednisolone in Complex Regional Pain Syndrome Treatment: A Systematic Narrative Review.

BACKGROUND Many patients with complex regional pain syndrome (CRPS) experience refractory pain with severe restrictions in the activities of daily living. Oral prednisolone is commonly used to treat these patients. PURPOSE To review previous studies assessing the effects of prednisolone in CRPS patients. METHODS AND MATERIALS Articles published from January 1, 1980 to July 23, 2021 in the PubMed database were searched using the following key phrases: (prednisolone OR corticosteroid OR steroid) AND (complex regional pain syndrome OR reflex sympathetic dystrophy OR shoulder hand syndrome OR causalgia). Specifically, we included those articles in which oral prednisolone or corticosteroids were used to control the CRPS symptoms. RESULTS In total, 11 articles were included, comprising 3 randomized trials, 5 single-arm prospective observational studies, and 3 retrospective studies. Nearly all previous studies reported that oral prednisolone can effectively control the CRPS symptoms. Moreover, though 30-100 mg/day of oral prednisolone was initially administered in these studies, 30 mg/day was also found to be effective in controlling the symptoms. Although prednisolone was usually administered for 1-3 months, short-term treatment for 1-2 weeks was also reportedly effective. Furthermore, only 0-30% of the patients in these studies had minor side effects after prednisolone treatment. CONCLUSIONS Our review showed that prednisolone may be effective in alleviating the CRPS symptoms. To determine higher levels of evidence, a full systematic review with more highly-qualified studies, such as randomized controlled trials, should be conducted in the future.