SHOULDER ARM PAIN FROM CERVICAL BANDS AND SCALENE MUSCLE ANOMALIES

Fourteen patients were identified with (1) pain and sensory changes in a brachial plexus distribution, (2) aggravation of pain with use of t he affected extremity, and (3) pain on palpation over the brachial ple xus. All patients had minimal or no intrinsic hand muscle atrophy. Onl y one patient had cervical ribs. Nerve conduction studies were normal, and electromyography (EMG) showed mild chronic neuropathic changes in 2 patients. None of the patients responded to conservative therapy ov er a prolonged period (7-12 months). A compressive brachial plexopathy from abnormally attached or enlarged scalene muscles that affected bo th upper and lower trunks of the brachial plexus was found at surgery in all patients. In 13 patients, at least one fibrous band compressed the lower trunk of the brachial plexus. Therefore, neurogenic thoracic outlet syndrome can occur from cervical bands and scalene muscle anom alies without intrinsic hand muscle atrophy, cervical ribs, enlarged C 7 transverse processes, or EMG abnormalities.