Scaphoid nonunion: does open reduction, bone grafting and Herbert screw fixation justify the treatment?

Abstract

Conventional bone grafting and Herbert screw fixation give satisfactory results for scaphoid nonunion; however, vascularized bone grafting has superior results, especially in the case of avascular necrosis of proximal fragment. Vascularized bone grafting is technically more demanding with small error of margin, problems of getting the appropriate graft, fixation and incorporation, and requires longer duration for wrist immobilization. Forty-five patients of scaphoid nonunion were treated by cancellous bone grafting, cortex containing graft if required and Herbert screw fixation. Functional outcomes were assessed at the latest follow up after surgery (minimum oneyear after surgery). The average pre-operative and post-operative scapho-lunate angle, grip strength, flexion-extension movement, radio-ulnar movement, scaphoid index and modified mayo score were improved from 49.60±6.40° (37-66) to 36.26±4.73° (range 28-46), 20.66±3.17kg (15-27) to 31.11±3.29kg (range 25-40), 78.57±14.22° (45-110) to 132.86±13.90° (100-165), 30.06±6.06° (20-44) to 44.95±6.37°(range 35-59), 0.66±0.076 (0.55-0.79) to 0.60±0.065 (range 0.49-0.73) and 58.66±5.24 (50-70) to 84.37±5.01 (range 75-95), respectively, with P value <0.001. Based on modified mayo score, 21 (46.7%) patients had excellent results, 19 (42.2%) had good results, 4 (8.9%) had fair results and one patient (2.2%) had poor results. Bone grafting and Herbert screw fixation provides a good option for treatment of scaphoid nonunion, especially in the absence of avascular necrosis of proximal fragment. More importantly, vascularized bone grafting in all scaphoid nonunion may not be necessary and could otherwise have been united uneventfully by this technique. However, avascular necrosis of proximal fragment must be ruled out pre-operatively as well as intra-operatively.