title: Vitamin C to Prevent Complex Regional Pain Syndrome in Patients With Distal Radius Fractures: A Meta-Analysis of Randomized Controlled Trials.
abstract: OBJECTIVE
  To determine whether vitamin C is effective in preventing complex regional pain syndrome (CRPS) in patients with distal radius fractures.
  
  
  METHODS
  MEDLINE (1946 to present), EMBASE (1974 to present), and The Cochrane Library (no date limit) were systematically searched up to September 6, 2014, using MeSH and EMTREE headings with free text combinations.
  
  
  METHODS
  Randomized trials comparing vitamin C against placebo were included. No exclusions were made during the selection of eligible trials on the basis of patient age, sex, fracture severity, or fracture treatment.
  
  
  METHODS
  Two reviewers independently screened articles, extracted data, and applied the Cochrane Risk of Bias tool. Evidence was graded using the Grading of Recommendations Assessment, Development, and Evaluation approach.
  
  
  RESULTS
  Heterogeneity was quantified using the χ test and the I statistic. Outcome data were combined with a random effects model.
  
  
  RESULTS
  Across 3 trials (n = 890) of patients with distal radius fractures, vitamin C did not reduce the risk for CRPS (risk ratio = 0.45; 95% confidence interval, 0.18-1.13; I = 70%). This result was confirmed in sensitivity analyses to test the importance of missing data because of losses to follow-up under varying assumptions. Heterogeneity was explained by diagnostic criteria, but not regimen of vitamin C or fracture treatment.
  
  
  CONCLUSIONS
  The evidence for vitamin C to prevent CRPS in patients with distal radius fractures fails to demonstrate a significant benefit. The overall quality of the evidence is low, and these results should be interpreted in the context of clinical expertise and patient preferences.
authors.affiliation: Division of Orthopaedics, Department of Surgery, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Nathan
authors.initials: N
authors.lastname: Evaniew
authors.forename: Colm
authors.initials: C
authors.lastname: McCarthy
authors.forename: Ydo V
authors.initials: YV
authors.lastname: Kleinlugtenbelt
authors.forename: Michelle
authors.initials: M
authors.lastname: Ghert
authors.forename: Mohit
authors.initials: M
authors.lastname: Bhandari
mesh_terms: D000284:Administration, Oral; D000975:Antioxidants / Q000008:administration & dosage; D001205:Ascorbic Acid / Q000008:administration & dosage*; D015984:Causality; D015897:Comorbidity; D020918:Complex Regional Pain Syndromes / Q000453:epidemiology* / Q000517:prevention & control*; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D010147:Pain Measurement / Q000187:drug effects / Q000706:statistics & numerical data; D011885:Radius Fractures / Q000188:drug therapy* / Q000453:epidemiology*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012307:Risk Factors; D017678:Sex Distribution; D016896:Treatment Outcome; D014954:Wrist Injuries / Q000188:drug therapy / Q000453:epidemiology
chemical_list: D000975:Antioxidants; D001205:Ascorbic Acid