Scaphoid nonunions treated with corticocancellous graft and Herbert screw fixation: results at the 10-year follow-up

Abstract

BackgroundFracture of the scaphoid bone is the most common fracture of the carpus and frequently, diagnosis is delayed as the unique anatomy and blood supply of the scaphoid itself predisposes to delayed union or nonunion. The Herbert screw is a double-threaded screw that provides superior compression compared with other devices used for internal fixation of scaphoid nonunion.ObjectivesThe aim of this study was to evaluate the outcome and presence or progression of degenerative changes in the wrist after corticocancellous bone grafting and Herbert screw fixation.Patients and methodsThis study reviewed 20 patients with scaphoid nonunion who had been operated with a corticocancellous graft and Herbert screw fixation 10 (3.5-11) years previously, all free from arthritic changes preoperatively. The age of the patients at surgery ranged from 17 to 38 years, mean 24.9 years. The interval between trauma and surgery ranged from 8 to 60 months, mean 19.55 months.ResultsThe function of the operated wrist was evaluated according to the scaphoid outcome score (SOS). Only three patients failed to show union. The mean (SOS) was 8.3 (5-10). Flexion was 11.7%, extension was 14.5%, ulnar deviation was 24%, radial deviation was 27.5%, and gripping force was 14.8% to the normal side. Osteoarthritis was present in six patients; this was related to the absence of correction of the preoperatively existing dorsiflexed intercalated segment instability. There was a correlation between the radiological presence of osteoarthritis and the clinical outcome.ConclusionHerbert screw fixation and volar wedge corticocancellous grafting of scaphoid nonunion is a successful operation, with few complications, that produces excellent to good long-term results because of correction of dorsiflexed intercalated segment instability deformity and reduced progression of osteoarthritis in most cases.