The Role of Vascularized Nerve Grafting in Upper Extremity Reconstruction: A Systematic Review.

Purpose: Vascularized nerve grafts (VNGs) have been proposed as encouraging alternatives to conventional nerve grafting; however, there is ongoing debate regarding the clinical advantages of the approach compared with standard grafting. This review aims to gather and analyze reported cases of upper extremity nerve repair using VNGs documented in the published literature. Methods: In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, PubMed/MEDLINE, Embase, and Cochrane were searched. Inclusion criteria for this review included the following: (1) human subjects or cadaveric studies, (2) describing a vascularized nerve grafting procedure or suggesting a nerve and vascular supply for a potential vascularized nerve graft, and (3) upper extremity nerve repair in clinical studies. Results: Data were extracted from 45 clinical studies. Of 535 patients, the most common injury pattern was root avulsion and rupture (88.7%). The most utilized VNG was the ulnar nerve (72.8%), followed by nerve to long head of triceps (8.8%) and sural nerve (8.2%); most common recipients were median (57.6%), axillary (12.5%), and musculocutaneous nerves (11.9%). Between patients who had medical research council scale scores, 69% had functional (M3 and above) motor and 72.7% sensory (S3<) recovery. Conclusions: Vascularized nerve grafts can increase the odds of functional gain in challenging conditions such as large nerve gaps, nerve avulsions, ruptures, and scarred and irradiated beds. With the exception of well-known VNG options, literature on alternative VNGs is largely confined to case reports and series, with additional published cases, outcomes, and basic science research needed to establish the role of VNGs in nerve repair. Clinical relevance: Our findings support the promise of VNGs for complex cases of nerve reconstruction. Evidence from published cases also indicates that VNGs enhance motor and sensory function recovery compared with traditional nerve grafting.