[Paralytic shoulder secondary to post-traumatic peripheral nerve lesions in the adult]

Abstract

A critical review is presented of the indications for nerve repair or transfer and for palliative operations in the management of paralytic shoulder following traumatic neurological injuries in the adult. Different situations are considered: paralytic shoulder following supraclavicular lesions of the brachial plexus, following retro- and infraclavicular lesions and following lesions to the terminal branches of the plexus (axillary, suprascapular and musculocutaneous nerves) and finally problems related to lesions of the accessory nerve and the long thoracic nerve. I. Supraclavicular lesions of the brachial plexus. In complete (C5 to T1) lesions, the possibilities for nerve repair or transfer are at best limited, and the aim is to restore active flexion of the elbow. Palliative operations may be associated in order to stabilize the shoulder. In case of a complete C5 to T1 root avulsion, amputation at the distal humerus may be considered but is rarely performed combined with shoulder arthrodesis if the trapezius and serratus anterior muscles are functioning. The shoulder may also be stabilized by a ligament plasty using the coracoacromial ligament. In cases where the supraspinatus and long head of the biceps have recovered, but where active external rotation is absent, function may be improved by derotation osteotomy of the humerus. In partial C5,6 or C5,6,7 lesions, the indications for nerve repair and transfer are wider, as well as the indications for muscle transfers. In C5,6 lesions, a neurotization from the accessory nerve to the suprascapular nerve gives 60% satisfactory results; this is also true following treatment of C5,6,7 lesions, whereas restoration of active elbow flexion is obtained in 100% of cases in C5,6 lesions but only in 86% in C5,6,7 lesions. In cases where shoulder function has not been restored, palliative operations may be considered: arthrodesis or, more often, derotation osteotomy of the humerus which can be combined with transfer of the teres major and latissimus dorsi. II. Retro- and infraclavicular lesions of the brachial plexus. Twenty-five percent of the lesions of the brachial plexus occur in the retro- or infraclavicular region and involve the secondary trunks, most commonly the posterior trunk. Nerve repair should be performed early. The shoulder may be affected owing to involvement of the axillary nerve in cases of lesions of the posterior trunk, often associated with a lesion of the suprascapular nerve. Regarding the terminal branches (axillary, suprascapular and musculocutaneous nerves), spontaneous recovery may be expected in a significant proportion of cases but is often delayed (6-9 months), and the problem is to avoid unnecessary operations while not unduly delaying surgical repair in cases where it is indicated. MRI may be useful to delineate those cases where surgery is indicated: repair is usually performed around 6 months following trauma. Isolated lesions of the axillary nerve may be repaired with good results using a nerve graft. The lesion may occur in combination with a lesion of the suprascapular nerve; the latter may be interrupted at several levels. Proximal repair may be performed using a nerve graft; distal lesions are more difficult to repair and may require intramuscular neurotization. Lesions of the musculocutaneous nerve may be repaired with good results using a nerve graft. Lesions of the axillary nerve may be seen associated with lesions of the rotator cuff. The treatment varies according to the age and condition of the patient and according to the condition of the cuff muscles and tendons: in a young patient with avulsion of the tendons from bone, cuff reinsertion is indicated; in an older patient, the cuff must be evaluated by MRI or arthroscan, and repair is indicated unless the cuff tear is not amenable to surgery or there is fatty degeneration of the muscles. Palliative surgery may be indicated in cases seen late or after failed attempts at nerve repair. (ABSTRACT