Volar Radius Vascularized Bone Flaps for the Treatment of Scaphoid Nonunion.

Vascularized bone flaps (VBFs) improve union rates for scaphoid nonunions compared with nonvascularized grafts. Volar VBFs are indicated in cases of scaphoid nonunion with avascular necrosis and/or humpback deformity. Four volar VBFs are described in this article. The volar carpal artery and pronator quadratus VBFs are most commonly used. The pisiform VBF can be used for replacement of the proximal pole of the scaphoid; it is covered by articular cartilage. The ulna VBF has greater donor morbidity; the ulnar artery is harvested and a palpable donor site deformity results.