Vascularized bone graft from the iliac crest for the treatment of nonunion of the proximal part of the scaphoid with an avascular fragment

Abstract

Background: It was hypothesized that nonunion of the proximal third of the scaphoid associated with avascular necrosis could be treated successfully with a free vascularized bone graft obtained from the iliac crest.

Methods: Fifteen patients who had a nonunion of the proximal part of the scaphoid that had been present for an average of two years and three months (range, nine months to seven years) were managed with use of a free vascularized bone graft obtained from the iliac crest. Avascularity of the scaphoid, as assessed on preoperative radiographs, was characterized by loss of trabecular structure, collapse of subchondral bone, and formation of bone cysts. The results of the procedure were assessed in terms of osseous union, pain, active motion of the wrist, and osteoarthritis. Postoperatively, vascularity of the scaphoid was evaluated with use of magnetic resonance imaging and color Doppler ultrasonography. The average duration of follow-up was six years and one month (range, two years and one month to eight years and one month).

Results: Preoperatively, one patient had had pain with any movement of the wrist and fourteen had had pain after strenuous manual labor or sports activity. The average pain score, derived with use of a 10-point visual analog scale, was 2.4 points (range, 1.0 to 6.7 points). Postoperatively, union was achieved in twelve patients; six were pain-free, and six had occasional pain during strenuous manual labor or sports activity, or both. The average pain score for these twelve patients was 1.1 points (range, 0.0 to 4.2 points) on the visual analog scale. Preoperatively, osteoarthritis was limited to the region between the radial styloid process and the distal part of the scaphoid in fourteen patients and to the radioscaphoid region in one patient. Postoperatively, the degree of osteoarthritis remained unchanged in seven of the twelve patients who had union and progressed to the radioscaphoid region in five. Vascularity, as seen on the imaging studies, was restored in all twelve patients who had union. The nonunion persisted in three patients, all of whom had progressive osteoarthritis leading to carpal collapse.

Conclusions: The index procedure was successful in twelve of the fifteen patients who had a symptomatic nonunion of the proximal part of the scaphoid associated with avascular necrosis and osteoarthritis that was limited to the radioscaphoid joint.