Assessment of Union Rates in Ballistic Hand Fractures.

Abstract

Background: Ballistic hand fractures (BHFs) are complex, multistructure injuries, unique from other hand fractures. We sought to determine BHF union rates and assess factors contributing to nonunion.

Methods: Metacarpal or phalangeal BHFs sustained from 2016 to 2023 were identified from an institutional database. Charts and radiographs were reviewed for fracture characteristics and union by 90 days. Fractures without union by 90 days or without minimum 90-day follow-up were excluded. Comminuted fractures were categorized by severity: (1) complete bone loss (NC); (2) partial bony contact (PC); or (3) full (>80%) bony contact (FC). Univariate and multivariate analysis was performed to determine factors associated with nonunion.

Results: Ninety-seven BHFs were included. Most were comminuted (78.4%, N = 76). Greater fracture severity was associated with larger bony gap (FC: 2.2 vs PC: 10.2 vs NC: 24.0 mm; P < .001). The overall union rate was 48.5% (N = 47); however, less severe BHF (ie, noncomminuted, FC) had higher rates of union than more severe BHF (ie, PC and NC; 93% and 60.5% vs 36% and 7.7%; P = .003). On multivariate regression, bony gap was an independent predictor of nonunion (P = .02). Thirteen BHFs underwent additional surgery with 90% achieving union within 90 days.

Conclusions: Ballistic hand fractures treated with a single surgery demonstrate low union rates (48.5%). Two-stage reconstruction should be considered in all BHFs to improve union rates, particularly when severe comminution or large bony gaps are present. Following stabilization and soft tissue coverage, a second stage with conversion to internal fixation, debridement of devitalized bone, and secondary bone grafting should be performed.