Upper plexus thoracic outlet syndrome: optimal therapy.

Background: Previously, transaxillary first rib resection alone was not considered adequate therapy for "upper plexus" (median nerve) thoracic outlet syndrome. It was thought that the "combined" approach with upper plexus dissection through a supraclavicular incision in addition to the transaxillary approach was necessary. However, with better understanding of anatomy--that the median nerve receives fibers from C8 and T1 as well as the upper plexus and that muscles that compress the upper plexus attach to the first rib--it is now recognized that first rib removal alone will relieve upper plexus compression.

Methods: Assessment of 2,210 operations for thoracic outlet syndrome revealed 250 patients (11%) had symptoms and nerve conduction velocity slowing of the median nerve only (upper plexus), whereas 452 (20%) patients had both median and ulnar nerve compression (upper and lower), and 1,508 patients exhibited compression symptoms and nerve conduction velocity slowing of the ulnar nerve alone (lower plexus).

Results: Transaxillary first rib resection relieved symptoms of median nerve (upper plexus) compression as well as it did for ulnar nerve (lower plexus) compression. Treatment outcome comparisons of patients with median and ulnar compression show no significant differences.

Conclusions: These data refute the need for supraclavicular or combined supraclavicular and transaxillary approaches to treat patients with upper plexus (median) thoracic outlet syndrome compression as previously recommended. The transaxillary approach alone is satisfactory.