Role of Nerve Transfer in Treatment of Traumatic Adult Upper Brachial Plexus Avulsion

Abstract

SUMMARY B rachial plexus is a complex neural structure consisting of four lower cervical and first thoracic ventral roots, functions to provide sensation and motor innervation to the skin and muscles of the chest and upper limb. Adult traumatic brachial plexus injuries can effects on the upper extremity function. Injuries causing root avulsion or rupture require intensive treatment and significantly affect patients’ quality of life. Upper root avulsions are devastating injuries because the patient loses both functions of shoulder abduction and elbow flexion. Even if distal innervation is unaffected (C7-T1), without shoulder and elbow stability the wrist and hand cannot perform daily activities. Patients with brachial plexus injuries must be evaluated and treated within an appropriate timeframe, typically within 6 to 7 months after injury. If a muscle remains for a long time without nerve input, it is less likely to be function normally in the future. This is true even if the muscle eventually recovers its nerve signals. A nerve transfer procedure is used when there are no functioning nerve stumps in the neck to which nerve grafts can be connected. In this procedure, a healthy donor nerve is cut and reconnected to the injured nerve to provide a signal to a paralyzed muscle. Restoration of shoulder abduction and elbow flexion is the aim of treatment upper brachial plexus avulsion. Shoulder abduction is controlled by supraspinous muscle from 0 degree to 15 degree which supplied by suprascapular nerve (C5,C6),and by deltoid muscle from 15 degree to 90 degree which supplied by axillary nerve(C5,C6). Elbow flexion is controlled by biceps and brachialis which supplied by musculucutaneous nerve (C5,C6). Our review summarized different types of nerves used as a donor nerve in nerve transfer in treatment of adult upper brachial plexus avulsion, and highlighting some details of procedure used, resulting in final functional result according to Medical Research Concil MRC. Spinal accessory nerve transfer to suprascapular nerve, radial nerve branch to long head of triceps transfer to anterior branch of axillary nerve, rootlet of contralateral C7 transfer to suprascapular nerve with sural nerve graft, phrenic nerve to suprascapular nerve, intercostal