ABSTRACT
To evaluate the root neurotization properties of extraplexal donor nerves, an avulsion
injury model of brachial plexus was created and repaired by C3,4 nerve-root transfers in the rabbit. Eighteen rabbits were divided into three groups.
In Group 1 (n = 6), the right C5,6 nerve roots were avulsed and bridged by a nerve graft taken from the femoral nerve,
with C3,4 as C3 to C5 and C4 to C6 . In Group 2 (n = 6), the right C5,6 nerve roots were cut and directly sutured end-to-end. Group 3 (n = 6) was a negative
group, in which C5,6 nerve roots were avulsed without repair. All three groups were positively controlled
by the contralateral side. Postoperative behavior observation and anatomic, electrophysiologic
studies were conducted 4 months later for comparison among groups. Axon existence
was observed by acetylcholinesterase staining. Results showed that active motion was
not found in all three groups by the end of the study. Extraplexal nerve transfer
indeed was able to re-neurotize the avulsed nerve roots down to their target organ,
but C3,4 nerve transfer was weaker than direct end-to-end suture, in terms of neurotization
ability. The authors conclude that “root or trunk repair” for avulsion injury of the
brachial plexus is possible, provided that the donor nerve has enough fibers and the
nerve regeneration ability is increased by modern moleculobiologic techniques.
KEYWORDS
Brachial plexus - avulsion injury - nerve transfer