Abstract
The results of 13 patients with end-to-side anastomosis of the axillary nerve to various donor nerves were presented. The results were evaluated by means of functional and electrophysiological methods following avulsion and subsequent reconstruction of the brachial plexus.
End-to-side anastomosis of the rat musculocutaneous nerve (n = 12), with the ulnar one, was used in the experimental model. The retrograde tracers were applied to prove the reinnervation.
Fair and good results were achieved in neurotization of the axillary nerve in 75% of patients with follow-up longer than 24 months. Electrophysiology proved reinnervation in 100% of the patients.
The average muscle strength, according to the muscle test, was 3.80. The functional recovery started within 7-12 months postoperatively.
Retrograde staining in the experimental model demonstrated the reinnervation of the rat bicep muscles after 3 months from end-to-side anastomosis, mainly by collateral reinnervation from the ulnar nerve. The ulnar nerve motoneurons (70 +/- 13) were able to send off collateral sprouts from their intact axons into the musculocutaneous nerve.
Other motoneurons of the same pool (21 +/- 4) regenerated axons directly into the musculocutaneous nerve without collateral sprouting, probably due to the axonotmesis of the motor fibers during the preparation of the perineurial window. Our results demonstrated that end-to-side anastomosis of the peripheral nerve might successfully be used for reinnervation procedures of a brachial plexus injury, mainly in cases with insufficient sources of motor nerve fibers from neighboring intact motor nerves.