[Pedicled vascularized bone graft for scaphoid reconstruction after Zaidemberg]

Abstract

Background: Nonunion of the scaphoid as a result of proximal fractures, failed surgical reconstruction, and especially avascular fragment necrosis are possible indications of vascularized bone grafts. Various techniques of vascularized (pedicled and free) grafts have been described. Pedicled grafts from the direct vicinity of the wrist provide several benefits. Harvest-site morbidity is reduced and preserved graft perfusion, without the need for blood vessel anastomosis, may lead to an improved consolidation.

Methods: A common pedicled vascularized bone graft for reconstruction of the scaphoid was first described by C. Zaidemberg and colleagues in 1991. We describe 49 consecutive patients, who underwent vascularized bone-grafting, pedicled on the 1.2 intercompartmental, supraretinacular artery in a modified technique based on Zaidemberg's description. The fixation of the bone graft was performed by Kirschner wires.

Results: A consolidation was detected in 37 cases, and 9 cases showed a persistent nonunion (3 patients did not follow up). According to the classification of Herbert, 44 patients had a nonunion grade D2 or higher, of which 36 patients showed a bony consolidation (8 non-consolidated). Complications occurred in individual cases (1x intraoperative fracture of the radius, 4x transient irritations of the superficial branch of the radial nerve). A loss in the range of motion of the affected wrist was frequent. An indication for a pedicled graft was seen if the preoperative contrast-enhanced MRI showed an impaired perfusion of scaphoid fragments.

Discussion: The more advanced the changes in MRI, the more frequently treatment failed. The vascularized bone graft from the dorsal distal radius described by C. Zaidemberg et al. is one of several ways to address a circulation-impaired nonunion of the scaphoid.

Keywords: Grafting, bone; Injuries, wrist; Os scaphoideum; Pseudoarthrosis; Scaphoid non-union.