Abstract
Background: Complex regional pain syndrome (CRPS) is a disabling post-traumatic pain condition that may occur after distal radius fracture (DRF), potentially impairing recovery and upper-limb function. Identifying effective preventive strategies after DRF is therefore clinically important. Objective: To synthesize and critically appraise interventions intended to prevent CRPS after DRF, including rehabilitation protocols and clinical prophylaxis strategies. Methods: This systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses PRISMA and was registered in the International Prospective Register of Systematic Reviews PROSPERO (CRD42023408499). Five databases (PubMed, Web of Science, Scopus, ScienceDirect, and B-on) were searched for studies published from January 2013 to 22 September 2023 in English, Portuguese, or Spanish. The primary outcome was CRPS incidence after DRF. Findings were synthesized narratively due to heterogeneity in interventions and diagnostic criteria, and risk of bias was assessed using design-appropriate tools. Results: Nine studies were included (total N = 7075; CRPS cases n = 127). Interventions comprised vitamin C supplementation (2 studies), probiotics, aspirin, polarized/polychromatic light therapy plus conventional treatment, early rehabilitation/home-exercise programs, and general CRPS-prevention protocols after DRF. Probiotics and aspirin did not reduce CRPS incidence. Vitamin C showed mixed findings across the included studies and remains debated in the broader literature. Light therapy was associated with reduced CRPS occurrence in a single study, while early active home-exercise programs appeared promising but were supported by a limited number of studies. Study designs and CRPS diagnostic criteria varied, and risk of bias was moderate-to-serious in several non-randomized studies. Conclusions: Evidence remains insufficient to support a single standardized prevention protocol for CRPS after distal radius fracture. Early active rehabilitation and progressive mobilization appear promising, but the available evidence is still limited and heterogeneous. Adjunctive strategies such as vitamin C and light therapy should be interpreted with caution, as findings for vitamin C remain debated in the literature and the evidence for light therapy is currently based on a single study. Other approaches, including probiotics and aspirin, have shown inconclusive results.