Vascularized Radial Periosteal Pedicled Flap for Recalcitrant Ulnar Nonunion in Children: Anatomical Study and Case Report.

Abstract

Pediatric cases of bone nonunion are rare and often a result of complex local vascular limitations. The periosteum plays a key role in bone healing through its regenerative properties. Vascularized periosteal grafts have previously been effective in treating complex cases. This study explores the vascular anatomy of the radial periosteum supplied by the anterior interosseous vessels and introduces the vascularized radial periosteal graft (VRPG), successfully implemented in a case of ulnar nonunion. Cadaveric studies of ten upper limbs were conducted under ×2.5 loupe magnification following injection of colored natural latex through the brachial artery. Anterior interosseous vessels (AIOV) branches supplying the radial shaft periosteum were studied with regards to AIOV length, number of periosteal branches, and their respective distances from the distal radioulnar joint (DRUJ). As part of our case report, two pediatric cases of complex ulnar shaft nonunion underwent treatment with a VRPG: one a 15-year-old with a multioperated ulnar nonunion and the other a 5-year-old with congenital pseudoarthrosis. The mean AIOV length was 15.9 cm (range 14.2-17.8). They were found to have an average of 9.6 (range 8-13) periosteal branches with a mean distance to the DRUJ of 16 mm (range 11-23 mm) from the most distal branch and 111 mm (98-136) from the most proximal periosteal branch. Case report follow-up of both cases showed a very early initially ossified prominent callus and early bone union and callus remodeling with excellent function. The AIOV reliably supplies the radial periosteal shaft, allowing for successful harvest of a pedicled periosteal flap. This flap has proven effective in treating 2 cases of pediatric ulnar nonunion and warrants further evaluation and consideration in similar cases in the future.