Although transaxillary first rib resection is one of the popular treatments for thoracic outlet syndrome today, recurrences and nerve injuries have led to investigation of other operations that might reduce complications and improve results. This article compares the results of transaxillary first rib resection with (1) scalenectomy (anterior and middle) and (2) supraclavicular first rib resection with scalenectomy. Between 1964 and 1987, 668 primary operations were performed for thoracic outlet syndrome on 491 patients. Seventy-one percent were women. Eight-six percent gave histories of neck trauma, often a whiplash injury (traumatic thoracic outlet syndrome); 4.5% had cervical ribs. Common symptoms included paresthesia in the hands (90%); arm pain (80%); neck pain (86%); and occipital headaches (69%). On physical examination, tenderness over the scalene muscles and duplication of symptoms with the arms abducted to 90 degrees in external rotation were present in over 90% of patients. By use of life-table analysis methods, success after surgery was found to be the same for all operations: 91% to 93% at 3 months; 76% to 79% at 1 to 2 years; 70% to 73% at 3 to 5 years; and 69% to 72% at 5 to 10 years. After rib resection plexus injuries occurred in 2.6%, with partial disability in 0.5%. No plexus injuries occurred after scalenectomy, but temporary phrenic nerve palsy occurred in 4.4%. Scalenectomy is as successful an operation as first rib resection for traumatic thoracic outlet syndrome and has fewer serious complications.(ABSTRACT TRUNCATED AT 250 WORDS)