Emergency Medical Technician (EMT) Intermediate Practice Exam

What symptom indicates that a patient may be experiencing thoracic outlet syndrome?

1. Acute chest pain

2. Numbness in the arms

3. Severe headache

4. Rapid heartbeat

The correct answer is: Numbness in the arms

Thoracic outlet syndrome (TOS) occurs when the blood vessels or nerves in the thoracic outlet, the area between the collarbone and the first rib, become compressed. One of the hallmark symptoms of this condition is numbness or tingling in the arms and hands. This symptom arises because the brachial plexus—a network of nerves that controls the muscles and sensation for the arm—can be affected. Patients may describe sensations of weakness, pain, or numbness that can radiate down to the fingers, indicating a disruption in normal nerve function. The other symptoms listed, while they can indicate various medical conditions, do not specifically point toward thoracic outlet syndrome. For instance, acute chest pain is often associated with cardiac events or other thoracic pathology, severe headaches may suggest neurological issues or vascular conditions, and a rapid heartbeat can reflect a variety of systemic responses such as stress, anxiety, or other cardiac problems. However, the presence of numbness in the arms is distinctly linked to the nerve compression characteristic of TOS.