Divergent Dislocation of the Carpometacarpal Joints: A Case Report and Systematic Review.

Background: A divergent carpometacarpal dislocation is a rare, high-energy, multijoint injury where the metacarpals are dislocated in opposite directions. This differs from the more common, lower energy, single-joint carpometacarpal dislocations that feature unidirectional displacement. We report the case of a 55-year-old patient who sustained this injury and provide a systematic review of its presentation, management, and outcomes. Methods: Clinical details for the case report were obtained from hospital records. A comprehensive literature search in English was conducted across PubMed/MEDLINE, Embase, Scopus, Web of Science, and Google Scholar, and completed on September 15, 2024, to identify studies on divergent carpometacarpal joint dislocations. Results: Out of 103 records, after duplicate and irrelevant records were removed, 18 reports were assessed, 4 were excluded, and 14 case reports from the literature, plus the authors' case report, were included, totaling 15 studies. Men made up 93.3% (n = 14) of patients, with an average age of 32 years. Road-traffic accidents caused 73.3% (n = 11) of injuries. Divergence most often occurred between the second and third joints (46.7%, n = 7). Dislocation of 4 carpometacarpal joints occurred in 66.7% (n = 10) of cases, and most injuries involved the dominant hand (90.9%, n = 10). Open reduction and percutaneous pinning were used in 53.3% (n = 8). Conclusions: Divergent carpometacarpal dislocations are rare injuries caused by high-energy trauma and mainly affect young adults. Prompt diagnosis and treatment generally lead to good recovery. Evidence is limited to case reports, and collaborative research is needed to develop treatment guidelines.