ZocdocAnswersWhat additional tests can be done to diagnose thoracic outlet syndrome in both the neurogenic and vascular cases?

Question

What additional tests can be done to diagnose thoracic outlet syndrome in both the neurogenic and vascular cases?

I have symptoms in both my arms. I cannot sleep at nighttime on my side because the arm that is underneath will fall asleep in under five minutes (starts off with numbness in the upper arm and shoulder and escalates down to fingers). This is regardless of where I place the arm. When standing, if my arm is raised above my head and my neck is turned to the right, my pulse rate is almost completely gone (checked by a nurse). This suggests that something is pinching on nerves, veins, arteries, etc. and is cutting off blood flow. An MRA of the neck showed no restriction in blood flow. An EMG picked up abnormal nerve signals in the neck. An MRI showed a reverse curve in the neck and a bulging disc, but not touching the spinal cord. What additional tests can be done to conclusively diagnose thoracic outlet syndrome in both the neurogenic and vascular cases and possibly both?

Answer

Thoracic outlet syndrome occurs when the nerves, arteries, or veins that feed the arm are compressed as they are leaving the chest, leading to symptoms such as weakness or numbness and tingling, swelling, and decreased blood flow. Diagnosing this condition requires close coordination between several medical specialists, including a neurologist and vascular medicine specialist. I have a couple of general comments. The first is that the loss of pulse when raising the arm and turning the neck, which is also known as the Adson test, is often falsely positive, and therefore this finding should not be used to diagnose (or even, really, suspect) the condition. On the other hand, the fact that the MRA of the vessels in the neck and chest was negative makes vascular thoracic outlet syndrome much less likely, although MRA is not always the best test to be used in this situation. If your doctors have a high enough suspicion, they may recommend additional testing, such as ultrasound or CT angiography. EMG is the main test used to diagnosis neurogenic thoracic outlet syndrome, and it sounds like the findings were negative in your case. Sometimes, if the suspicion remains high, injecting nerve blocking medications and looking for improvement can be useful. I'd suggest talking about these possibilities with the doctor who is managing your case.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

If you think you may have a medical emergency, call your doctor or (in the United States) 911 immediately. Always seek the advice of your doctor before starting or changing treatment. Medical professionals who provide responses to health-related questions are intended third party beneficiaries with certain rights under Zocdoc’s Terms of Service.