Vascularized Ulnar Nerve Graft: Outcomes in 151 Repairs

Vascularized nerve grafts (VNG) were introduced in 1976. Since then, experimental and clinical studies have suggested their superiority. In this study, the authors presented 23 years of experience with the ulnar VNG.

Between 1981 and 2004, 151 reconstructions with the ulnar nerve have been performed in a center for brachial plexus injuries. Patients were divided into four different groups so analysis would be possible: pedicled (n = 25), and free (n = 21), VNG from ipsilateral donors and VNG to median nerve (n = 13) and to single motor targets (n = 8) from contralateral donors.

In all groups, late cases yielded significantly inferior results to patients who were operated on early, and age of the patient showed a negative correlation with an increase in postoperative muscle grading. Free ipsilateral nerve graft produced inferior results to pedicled ipsilateral nerve graft for deltoid and triceps, but superior results to contralateral nerve grafts. For median nerve reconstruction in the ipsilateral group, motor function was achieved in only a small group of patients who combined young age with short denervation time. In the contralateral group, all the patients except one (19.6%) achieved at least protective sensation. In the contralateral group, there was a significant difference between resulting muscle grading when the median nerve was the target vs. when single motor targets like axillary, MC, or triceps were neurotized. In this second group, denervation time was very important in muscle function restoration. Biceps muscle strength improvement was less than the improvement produced in the ipsilateral group. VNG yielded better outcomes compared to conventional nerve grafts in a previous study (protective sensation in the hand was achieved in 51% of cases compared to 91.6% with VNG. For the biceps, the ipsilateral pedicled VNG yielded excellent results in 28% of the patients and poor results in 37.5% (for conventional nerve grafts, excellent results were found in 12% and poor results in 28%). Better outcomes were also found for the triceps and deltoid with the use of VNG.

Vascularized ulnar nerve grafts resulted in superior outcomes over conventional nerve grafts in brachial plexus injuries. During this 23-year period, only few changes have been made over time. The strategy is as follows: for brachial plexus injuries with C8, T1 root avulsion, the vascularized ulnar nerve graft is the procedure of choice. Neurotization of single motor targets, in young patients, early after injury, yield the most rewarding results.