The Effect of Smoking on the Outcomes of Vascularized Bone Graft Surgery in Scaphoid Nonunion through Meta-analysis

Abstract

Purpose: A vascularized bone graft is an option showing a good result to treat scaphoid nonunion. The analysis of the effects of smoking, which affects vascular and union of fracture, has been limited. We tried to analyze the effect of smoking on the outcomes of vascularized bone graft in scaphoid nonunion through meta-analysis Methods: Two researchers analyzed 923 papers searched for ‘scaphoid AND (vascularized OR vascularised OR flap OR pedicled)’ on MEDLINE and Embase (until November 2020). We selected 31 papers which contain that vascularized bone graft was performed for scaphoid nonunion, and the number or proportion of smokers could be confirmed. Through meta-regression analysis and subgroup analysis, whether the smoker’s rate had an effect on union rate, union period, functional score, imaging evaluation, range of motion, and complications rate was analyzedResults: A significant negative correlation between smoking and bone union rate was confirmed in pedicled vascularized bone grafting, and a significant positive correlation between smoking and bone union duration was confirmed in free vascularized bone grafting. Conclusion: It is necessary to have caution for nonunion when considering pedicled vascularized bone graft in smoking patients with scaphoid nonunion.