When C-5 and C-6 are avulsed the Spinal accessory (SA) nerve, which innervates the trapezius muscle, can be transferred to the Suprascapular nerve, just as it branches off the Upper trunk at Erbs point.
The SA nerve must be sacrificed after it has given some branches to the trapezius to avoid denervating that muscle. This transfer alone may restore anywhere between 10 and 60 degrees of shoulder forward flexion. When possible, an attempt at neurotizing the Axillary nerve is indicated. If the radial nerve (C-7) is uninvolved, the 1st branch to the long head of the triceps can be transferred to the axillary nerve as it exits the quadrangular space.
In the case reported in this article, all nerve roots were avulsed, and so, hand function was lost also. The 1st video shows the functional outcome after Spinal accessory to suprascapular nerve transfer (approximately 30-40 degrees of forward flexion). Because of poor hand function and unsuccessful restoration of elbow flexion, he elected above elbow amputation and prosthetic fitting. The 2nd video shows nearly 90 degrees of shoulder forward flexion once the weight of his arm no longer needed to be overcome.
Nerve transfer surgery usually obviates the need for shoulder fusion in 75- 80% of cases so long as it is performed within the 1st 6 months after injury, and patient age is less than 50 years.
