Iliac crest bone grafting and herbert screw fixation of nonunions of the scaphoid with avascular proximal poles

Abstract

Between 1989 and 1991, 137 nonunions of the scaphoid were treated by the senior author, who noted that 26 of these nonunions had an avascular proximal pole (no punctate bleeding from the bone at the time of surgery). All 26 nonunions were treated with iliac crest bone grafting and Herbert screw fixation. Of these 26 patients, 17 were followed for more than 1 year after their surgery (average follow-up period, 31 months). The average time from injury to surgery was 31 months. Of the 17 patients included in this study, 12 were treated with a palmar approach to the nonunion, 5 with a dorsal approach. The 12 nonunions that occurred at either a midwaist or distal location were approached through a palmar modified Russe incision and treated with interpositional corticocancellous iliac crest bone graft in addition to the Herbert bone screw. The five nonunions with a very small proximal fragment were approached through a dorsal incision and treated with cancellous iliac crest bone graft and Herbert screw fixation. All patients were immobilized after operation in a short-arm thumb spica cast for 3 months and were then allowed active range of motion of their wrists. Return to full activity was permitted once preoperative wrist motion was restored. Radiographic union, as defined as bridging trabeculae of bone present in all x-ray films, occurred in nine patients, an incomplete union or persistent fibrous union in seven, and a nonunion in one patient. Using the scaphoid outcome score, an assessment scale based on pain, occupation, wrist motion, strength, and patient satisfaction, functional results were graded as excellent in six patients, good in five patients, fair in four patients, and poor in two patients. The average range of motion of the wrist did not significantly improve after surgery, but the average grip strength of the injured hand increased by 29 lbs. There were no intraoperative complications. However, three patients required further operative procedures including radial styloidectomy, pin removal, and carpal tunnel release. No patient has required either a proximal row carpectomy or wrist arthrodesis. Previously published results of avascular proximal pole scaphoid nonunions suggest that union cannot be obtained and functional results are uniformly poor. In contrast, the functional and x-ray results of our patients are markedly improved over these previous studies--emphasizing the importance of iliac crest bone grafting, rigid internal fixation, and appropriate postoperative immobilization.