This paper reviews three skeletally immature patients treated with a vascularized distal radius bone graft for a proximal scaphoid nonunion with avascular necrosis. The mean age at the time of the fracture was 15 years and the mean age at the time of surgery was 16.3 years. All injuries occurred during athletic events either following a fall onto an outstretched hand or during blunt trauma. The patients presented at a mean of 16.5 months post injury and were all subsequently treated with a cast without evidence of further healing. The fracture was described as minimally displaced in two patients and moderately displaced in one patient. The sizes of the proximal fragments were 15%, 20%, and 20% of the entire area of the scaphoid. A vascularized distal radius bone graft was performed at 6, 17 and 35 months post injury taken from the 1, 2 intercompartmental supraretinacular artery and fixed with three smooth k-wires. The fixation included a wire from the radial styloid to the distal scaphoid, a wire through the length of the scaphoid, and a wire from the distal scaphoid to the capitate. Two patients underwent a dorsal capsulodesis to correct the dorsal intercalated segment instability noted preoperatively. A long arm cast was maintained for one month followed by a short arm cast until healing. All fractures healed at a mean of 3.4 months postoperatively. All patients were examined clinically and radio-graphically at a minimum of five years after surgery. All scaphoids continued to show revascularization of the proximal pole without any evidence of degeneration of the radial-carpal joint. There was no evidence of carpal instability or collapse in any patient; however, the proximal part of the scaphoid was irregular in shape with a dorsal prominence where the graft had been placed. The lucency surrounding the previous nonunion sites all resolved. In addition, all patients were pain free, had no tenderness to palpation and participated in all activities without restriction. Dorsiflexion and radial deviation of the effected wrist were decreased by a mean of 22 degrees and 15 degrees, respectively.
Avascular necrosis associated with a nonunion of the proximal pole of a scaphoid in a skeletally immature patient is rare. Most fractures in adolescents involve the mid or distal pole of the scaphoid. This study reviewed one treatment method in three patients with uniformly good results. It essentially confirms the feasibility of a vascularized distal radius bone graft in skeletally immature patients. Care should be taken not to injure the physis of the distal radius. There was no comparison control group to a non-vascularized bone grafting with screw fixation. In addition, the need for the dorsal capsulodesis to correct an apparent dorsal intercalated segment instability is unsubstantiated, as well as, the need to cross the radial carpal and midcarpal joints with k-wires. Because of the low incidence of avascular necrosis and nonunion of proximal pole fractures in adolescence, more comparisons may not be possible. Therefore, recommendations on treatment appear to parallel those for the more common adult fracture pattern.
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J Bone Joint Surg