Johns Hopkins Surgery
July 23, 2015

Thoracic outlet syndrome (TOS) can be a bear to diagnose, but once it is, says vascular surgeon Ying Wei Lum, “we’re able to help a good 90 percent of our patients.”

Lum leads a team of providers who know this condition unusually well. Patients come from across the country, because Johns Hopkins is one of the few hospitals where TOS is diagnosed and treated. Why? “Thoracic outlet syndrome is rare, and diagnosis is hard,” Lum says. “No single test pinpoints the condition.” The Johns Hopkins team performs between 60 and 80 operations each year to reduce the TOS-causing problem: compression on the brachial plexus, subclavian artery or subclavian vein.

Anyone whose activities involve regular shoulder flexion and abduction and an elbow perched at shoulder height or higher is at risk for TOS. Other causes may be physical trauma, anatomic anomalies like a cervical rib, scalene muscle anomalies, tumors and even poor posture.

The vast majority of cases are injury-related and involve pressure from a scalene muscle, a supernumery cervical rib or both on nerve roots of the brachial plexus.

“This neurogenic type of TOS can go on for a long time and cause pain and even muscle atrophy,” says Lum. “But TOS involving the subclavian vein or subclavian artery should be treated more urgently.”

Compression of the subclavian vein can lead to thrombosis, a swollen arm, bluish color of the hand and fingers, and pain. It is usually managed initially with or without thrombolysis, followed by anticoagulation therapy. Surgery should be considered to prevent recurrent thrombosis. Arterial TOS, the least common and most urgent of the three conditions, poses a risk for subclavian aneurysms and a thromboembolic event that could lead to an ischemic arm.

Lum and his associates are researching ways to improve more accurate detection of TOS and prompt referral. He is also interested in research to determine patient selection to yield the best functional outcomes.

Recent research supports completely removing the first rib to prevent recurrence of symptoms in neurogenic TOS.

“We’re on solid footing to improve outcomes for even more patients,” says Lum.

To refer a patient: 410-955-5165