Thoracic outlet syndrome: Does fiction outweigh facts?

Thoracic outlet syndromes (TOS) can be classified as vascular-type TOS (arterial and venous), true neurologic TOS, and the more recently coined disputed neurologic TOS (disputed N-TOS). True neurologic TOS is a rare entity that presents clinically with wasting of the small muscles of the hand, with established pathoanatomy that responds to surgical treatment aimed at preventing progressive neurologic deterioration. Vascular TOS has specific objective clinical findings consistent with arterial compromise, venous compression, or both. Disputed N-TOS, on the other hand, is a vague, subjective pain syndrome with no specific underlying pathoanatomy, and no objective clinical and electrophysiologic findings. It is often treated with varied surgical approaches ranging from transaxillary first rib resection, resection of the scalenus anticus and various other muscles in the vicinity, to resection of various fibromuscular bands and ligaments and neurolysis of the supraclavicular brachial plexus. The results at long term follow-up are generally not encouraging in the posttraumatic disputed N-TOS group covered under a worker's compensation policy. Disputed N-TOS has become the most common indication for surgery for TOS in the United States, accounting for at least 90% of all operations. Diagnosis of disputed N-TOS cannot be made in the presence of the more common true distal peripheral entrapment neuropathies, such as carpal tunnel syndrome and cubital tunnel syndrome, even though it is tempting to bundle it and justify its diagnosis and existence with the clinical concept of double-crush injuries.