THERAPEUTIC SUBSTANCES

BACKGROUND: Complex regional pain syndrome type I (CRPS-I), previously known as reflex sympathetic dystrophy, is common after conservatively or surgicallytreatedwrist fractures. Several studies support the efficacy of vitamin C in preventing CRPS-I, although the data are somewhat conflicting. The primary objective of this systematic literature review and meta-analysis was to assess the efficacy of vitamin C therapy in preventing CRPS-I after a wrist fracture.

METHODS: Randomised, placebo-controlled trials of vitamin C to prevent CRPS-I after wrist fractureswere sought in the three main databases: PubMed (1980 to December 2015), CENTRAL (Central 2015, number 12), andEmbase (1980 to December 2015). Two authors worked independently to select articles. Data from selected articles were collected independently.

RESULTS: Three randomisedplacebo-controlled trials in a total of 875 patients were included.Treatment was non-operative in758/890(85.1%)fracturesand operative in 132(14.9%)fractures. Vitamin C supplementation was started on the day of the injury and continued for 50 days. In the group given 500mg of vitamin C daily, the risk ratio for CRPS-I was 0.54 (95%CI, 0.33-0.91;p=0.02).Thus, the risk of developing CRPS-I was significantly decreased by prophylactic treatment with 500mg of vitamin C per day. The heterogeneity rate was 65% (non-significant).

CONCLUSION: Daily supplementation with 500mg of vitamin C per day for 50 days decreases the 1-year risk of CRPS-I after wrist fracture.

LEVEL OF EVIDENCE: II, systematic review of level I and II studies.