Symptoms of Arterial TOS
Arterial TOS is rare and quite serious. The symptoms of arterial TOS are often sudden and severe. These symptoms are caused by sudden occlusion of one or more arteries in the affected arm. Arterial occlusion blocks blood flow to the arm, which may lead to severe complications if not diagnosed and treated promptly.

Symptoms of Arterial TOS
Patients with arterial TOS may present with acute arterial occlusion, local symptoms, intermittent arterial insufficiency, or chronic arterial insufficiency.
Patients with acute arterial occlusion may experience one or more of the 5 P’s:
- Pain
- Pallor
- Paresthesias
- Pulselessness
- Paralysis
Patients with these symptoms should seek immediate medical attention.
Local symptoms may include an aneurysm or a cervical rib. A patient may notice a cervical rib as a chronic hard lump at the base of their neck. A patient may feel a painless, pulsatile mass at the base of the neck. This pulsatile mass may represent a normal subclavian artery passing over a cervical rib, or a subclavian artery aneurysm.
Intermittent compression of the subclavian artery causes symptoms only in specific arm positions; in other words, symptoms only occur in those arm positions where extrinsic structures compress the artery. Some patients notice their arm “going to sleep” in certain arm positions, or when they wake up from sleep.
Chronic or intermittent compression of the artery may cause scar or stenosis of the artery. As a result, chronically limited blood flow could cause chronic arm fatigue. Under those circumstances of chronically limited blood flow, the patient would experience claudication.
Claudication is a symptom complex resulting from narrowing of a major artery, usually to an arm or a leg. Symptoms of claudication usually progress over time.
Diagnosis of Arterial TOS
Your doctor will find evidence of arterial occlusion, including a cold and pulseless arm. Imaging tests can quickly and accurately demonstrate the presence of arterial aneurysm, blood clot, and occlusion. Learn more about the clinical diagnosis and imaging diagnosis of arterial TOS here.
Treatment of Arterial TOS
Critical treatment decisions revolve around the presence or absence of a blood clot causing arterial occlusion. When present, acute arterial occlusion demands urgent treatment. When absent, surgeons can assess and treat patients with arterial TOS less urgently. Learn more about the treatment of arterial TOS here.