Development of Apex Volar Deformity Following Volar Plating of Pediatric Radius Fractures

Plate fixation in skeletally immature children can cause angular deformity with longitudinal growth even when the plate does not overlie the adjacent physis. While this phenomenon has been described for the distal femur, angular deformity has not been reported following plating in other long bones. The aim of the study was to characterize whether sagittal-plane deformity occurs following volar plating of radius fractures in skeletally immature children and to determine associated risk factors.

A retrospective review of volar plating of acute radius fractures in children with an open distal radius physis at a single institution was completed. In patients with at least 4 months of follow-up, the first radiograph and the last follow-up radiograph were evaluated for any change in sagittal angulation distal to the plate. Demographic information was obtained from the electronic medical record. Linear regression analysis was used to determine if distance from the plate to the physis, follow-up time, age, or coexisting ulnar fracture was predictive of any observed changes in angulation.

Sixty-one acute radius fractures treated with volar plating at a mean age of 12.1 years (67% male, 70.5% White, 90.2% non-Hispanic) were included. When analyzing by fracture location, 78% (21/27) of the distal-third radius fractures with appropriate follow-up developed at least 10° of apex volar angular deformity, with 44% (12/27) exhibiting greater than 20°. Middle-third and proximal-third fractures did not exhibit similar degrees of angulation (only 13% [4/30] and 0% [0/4] of included patients developed more than 10° of deformity, respectively). Linear regression analysis revealed distance of the plate to the physis and follow-up time to be strong predictors of angulation (both p < 0.0001).

Children with radius fractures, particularly those in the distal-third, treated with a volar plate may develop apex volar angular deformity. While the exact rate of this phenomenon is unclear, these findings underscore the importance of strict surgical indications and vigilant postoperative monitoring beyond fracture healing, and represent a paradigm shift in understanding growth modulation following plating.

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.