Nonunion Rates Among Ulnar-Shortening Osteotomy for Ulnar Impaction Syndrome: A Systematic Review.

PURPOSE: The purpose of this study was to systematically review all available literature reporting nonunion rates of ulnar-shortening osteotomies (USO) used for the treatment of ulnar impaction syndrome (UIS) and to compare those rates among transverse versus oblique cuts for the osteotomy.

METHODS: Electronic databases including PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were searched for studies that evaluated outcomes of both transverse and oblique USO for UIS. Level of evidence was determined by 2 independent reviewers. Studies were screened based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and inclusion and exclusion criteria were applied. A total of 37 studies (1,423 patients) were included in final analysis. The average rate of nonunion and delayed union for each group (transverse and oblique osteotomy) was calculated.

RESULTS: The average rate of nonunion among all osteotomies was 4.0%. The average rate of nonunion was 4.16% and 3.86% in transverse osteotomies and oblique osteotomies, respectively. This difference was not statistically significant. The average rate of delayed union, in those studies that reported delayed union, was 5.7%. The average rate of delayed union was 7.41% and 4.1% in transverse osteotomies and oblique osteotomies, respectively.

CONCLUSIONS: Based on our review of the literature, there is no difference in the rate of nonunion between transverse and oblique osteotomies. Therefore, the decision of which of the 2 surgical techniques should not be based on rate of nonunion.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.