Treatment of scaphoid nonunion by vascularized bone flap pedicled on 1,2 ICSRA from the dorsum of the distal radius

Abstract

Objective To study the indication,techniques,and treatment outcomes of using a retrograde pedicled vascularized radius bone flap based on 1,2 intercompartmental supraretinacular artery ( 1,2ICSRA) to treat scaphoid nonunion.Methods Between February 2007 and October 2010,15 patients with established scaphoid nonunion were treated with open reduction and internal fixation in addition to a retograde pedicled vasculatized radius bone flap based on 1,2 ICSRA.Among these patients 9 had nonunion of the scaphoid waist and 6 had nonunion of the proximal pole of the scaphoid.9 patients were associated with avascular necrosis of the proximal fragments,3 with humpback deformity of the scaphoid and dorsal intercalated segment instability (DISI),and 2 with arthritis of radius styloid.In all cases a longitudinal incision was made through radial dorsum of the wrist.Bone graft was fixed with two cross Kirschner wires in 13 cases,and with one Herbert screw and one Kirschner wire in 2 cases.12 pedicled bone flaps were wedged in from the dorsum of the scaphoid,while 3 from the volar aspect of the scaphoid.Postoperative evaluation included the time to union,the range of motion of the wrist,pain relief and grip strength.Results Thirteen patients were follow-up and 2were lost.Duration of follow-up ranged from 6 to 21 months,with an average of 13 months.Union rate was 13 of 13 ( 100％ ) and the averaged union time was 14.2 weeks.All patients achieved complete pain relief.The flexion and extension of the wrist were (59.92±4.82)° and (49.73t±4.58)° respectively.The functional results were encouraging in all patients (9 excellent,2 good,and 2 fair),with an excellent and good rate of 84.6％,which were measured using the modified Mayo wrist score.Conclusion Retrograde pedicled vascularized radius bone flap based on 1,2 ICSRA can promote scaphoid union,especially for those patients associated with proximal pole avascular necrosis. Key words: Scaphoid bone; Fractures,ununited; Bone flap