Treatment of avascular proximal pole scaphoid nonunions with vascularized distal radius bone grafting.

Abstract

To investigate the outcomes of vascularized distal radius pedicled bone grafting secured with K-wires for scaphoid nonunions with small avascular proximal fragments. We included patients with scaphoid nonunions and small, avascular proximal fragments that were too small for screw fixation. The mean size of the proximal pole fragments was 21% (range, 9% to 28%) of the entire scaphoid, based on quantitative radiographic measurement. All patients had distal radius bone grafting based on the 1,2-intercompartmental supraretinacular artery pedicle and fixation with K-wires. There were 21 wrists in 18 men and 2 women with the mean age of 34 years (range, 22 to 57 y). The mean duration of postoperative follow-up was 40 months (range, 12 to 103 mo). Radiographic union and clinical outcomes, including the ranges of wrist motion, grip strength, and the modified Mayo wrist score, were evaluated. Union was achieved in 18 of 21 wrists (86%) at a mean time of 14 weeks after surgery (range, 8 to 28 wk). Nonunions with proximal fragments less than 20% of the total scaphoid healed in 6 of 8 wrists. In a subset of these 8 wrists in which the proximal fragment was less than 15%, healing occurred in 2 of 4. The modified Mayo wrist score significantly improved from 46 to 78 points, and final wrist functions were rated as excellent in 5, good in 5, fair in 10, and poor in 1. Ranges of motion and grip strengths did not show significant changes after surgery. Vascularized distal radius bone grafting and K-wire fixation can heal scaphoid nonunions with small avascular proximal fragments, although motion and grip strength remain unchanged. Healing may be related to the size of the proximal pole fragment.