Upper and lower trapezius muscle transfer to restore shoulder abduction and external rotation in longstanding upper type palsies of the brachial plexus in adults.

Lesions affecting the upper roots of the brachial plexus result in paralysis of shoulder abduction and external rotation. In longstanding lesions, neurological surgery is not recommended in which case muscle transfers become an option to improve shoulder function. We describe the surgical treatment of seven adult patients with longstanding lesions of the upper roots of the brachial plexus, in whom the upper trapezius muscle was transferred to the humeral head, whereas the lower trapezius muscle was sutured to the infraspinatous muscle tendon. Within an average of 11.7 months after surgery, patients had recovered 38° of abduction and 104° of external rotation, as measured from full internal rotation. The results of this preliminary series involving the combined transfer of both the upper and lower trapezius muscle seems promising for the treatment of chronic paralysis of abduction and external rotation following brachial plexus injury.