Management of scaphoid nonunion.

The primary risk factor for nonunion of the scaphoid is displacement/instability, but delayed or missed diagnosis, inadequate treatment, fracture location, and blood supply are also risk factors. Untreated nonunion leads to degenerative wrist arthritis-the so-called scaphoid nonunion advanced collapse wrist. However, the correlation of symptoms and disease is poor; the true "natural history" is debatable because we evaluate only symptomatic patients presenting for treatment. It is not clear that surgery can change the natural history, even if union is attained. The diagnosis of nonunion is made on radiographs, but computed tomography or magnetic resonance imaging scans can be useful to assess deformity and blood supply. Treatment options vary from percutaneous fixation to open reduction and internal fixation with vascularized or nonvascularized bone grafting to salvage procedures involving excision and/or arthrodesis of carpals.