17553 Thoracic Outlet Syndrome Tos
Informed by recognized medical guidance
Overview
Thoracic outlet syndrome (TOS) happens when the nerves or blood vessels between your collarbone and your first rib get squeezed. This space is called the thoracic outlet. It can cause pain, numbness, and weakness in your arm and hand.
Key facts
- TOS is more common in people who do repeated overhead movements, like swimming or painting.
- There are two main types: one affects nerves (more common) and one affects blood vessels.
- Many cases improve with physical therapy and postural changes.
TOS is not very common, but it is not rare either. It affects about 3 to 8 people in every 1,000.
It can affect anyone, but it is most often seen in adults between 20 and 50 years old. Women are more likely than men to develop it.
Symptoms
- Sudden severe swelling in your arm or hand
- A bluish or very pale color in your arm or hand
- Loss of pulse in your arm or hand
- Severe pain that comes on suddenly
- ⚠Numbness or weakness that is getting worse over hours or days
- ⚠Persistent coldness in your fingers
- ⚠Symptoms that follow a recent injury or accident
Common symptoms
- Pain or aching in the neck, shoulder, or arm
- Numbness or tingling in your fingers, especially the little finger and ring finger
- Weakness in your hand or arm
- Swelling or color changes in your arm, if a blood vessel is affected
Causes
Main causes
- Pressure on the nerves or blood vessels from tight muscles in the neck and shoulder
- An extra rib (cervical rib) that some people are born with, which narrows the space
- Repetitive movements, especially overhead activities like swimming, throwing, or painting
- Poor posture, such as slouching or holding a phone between your ear and shoulder
Risk factors
- Jobs or sports that require repeated reaching overhead
- Carrying heavy loads, like backpacks or equipment
- Obesity, which can increase pressure on the thoracic outlet
- Trauma to the neck or shoulder, such as whiplash from a car accident
When to see a doctor
See a doctor urgently if:
- If you have sudden, severe swelling or color changes in your arm, seek emergency care immediately.
- If you have new weakness in your arm or hand that is getting worse, see a doctor the same day.
Book a routine appointment if:
- If you have persistent pain, numbness, or tingling in your arm that does not go away with rest, make an appointment with your general practitioner.
Diagnosis
Your doctor will start by asking about your symptoms, medical history, and daily activities. They will examine your neck, shoulders, and arms. They may move your arms and head into certain positions to see if your symptoms come back.
Tests that may be done
- Physical examination tests, such as the Adson test or Roos test (these check for symptoms while your arms are in certain positions)
- Ultrasound or MRI scans to look at blood vessels or structures in your neck
- Nerve conduction studies, which check how well electrical signals travel along your nerves
What to expect at your appointment
The assessment is usually painless and may take 15 to 30 minutes. Your doctor may recommend imaging or nerve tests based on what they find. They will explain the results and possible next steps clearly.
Treatment
Treatment for thoracic outlet syndrome depends on the cause and how severe your symptoms are. Most people improve with conservative care — physiotherapy, posture changes, and activity adjustments. Surgery is only needed if these do not help or if a blood vessel problem is serious.
Self-care at home
- Improve your posture by sitting straight with your shoulders relaxed and your feet flat on the floor.
- Take regular breaks from repetitive overhead work or long periods of typing or driving.
- Do gentle neck and shoulder stretches as recommended by your physiotherapist.
- Apply heat to a tense area for 10 to 15 minutes, or cold if there is swelling, as comfortable.
Medical treatments
Your doctor may suggest physical therapy to strengthen your shoulder and neck muscles, and to improve your posture. They may also recommend simple pain management methods such as heat or cold, and may refer you to a specialist if symptoms continue. Some people benefit from injection of a numbing medicine around the nerves, but this should only be done by a trained professional.
When is surgery considered?
Surgery might be considered if you have severe nerve compression, a blood clot in the vein, or if symptoms do not improve after 3 to 6 months of conservative care. The surgery releases the pressure by removing part of the first rib or dividing a tight muscle. Your surgeon will explain the risks and benefits.
Living with this condition
Day-to-day living with TOS involves being aware of your posture and movements. Listen to your body — avoid positions that trigger pain or numbness. Many people find that ergonomic changes, like adjusting your chair and desk, make a big difference.
Lifestyle tips
- Quit smoking, as it can affect blood flow and make symptoms worse.
- Keep a healthy weight to reduce pressure on your shoulders and neck.
- Practice stress reduction techniques like deep breathing or yoga, as stress can tense your shoulder muscles.
Diet and exercise
A balanced diet rich in fruits, vegetables, and whole grains supports overall health. For exercise, focus on low-impact activities like walking or stationary cycling. Your physiotherapist can give you specific exercises to stretch and strengthen your upper body safely.
Mental health and emotional wellbeing
Living with chronic pain can be frustrating and may affect your mood. It is normal to feel worried or low at times. Talking to your doctor about your emotions is a good step. They can suggest support, including counselling if needed.
Prevention
While not all cases can be prevented, you can lower your risk by maintaining good posture, taking regular breaks from overhead work, and avoiding carrying heavy bags on one shoulder. Staying active and keeping your neck and shoulder muscles strong are also helpful.
Complications
If left untreated
- Permanent nerve damage, leading to chronic pain, numbness, or weakness in the arm and hand
- A blood clot in the vein (venous thrombosis), which can cause severe swelling and requires urgent care
- Reduced ability to use your arm for daily tasks, which can affect work and quality of life
Long-term outlook
The outlook for thoracic outlet syndrome is generally good. Most people improve significantly with physiotherapy and lifestyle changes. For those who need surgery, the success rate is high. With proper care and patience, you can expect to return to most of your normal activities over time.
Find support
External links open third-party websites. Ruqelo Health is not responsible for external content. Listing an organisation does not imply endorsement.
Always verify with your doctor
Health guidelines vary by country and region. The information in this article is based on international clinical guidelines but may not reflect the specific guidelines, medications, or practices in your country. Always discuss your health concerns with your own doctor or healthcare provider, and refer to your local national health guidelines where available.
Important notice This information is for educational purposes only. It does not replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider about your specific situation. If you are experiencing a medical emergency, call your local emergency services immediately.
Related conditions
Sources and guidance
This article is educational and is prepared with reference to recognized health information and clinical guidance sources where available. Specific source links may vary by topic.
Last updated: July 31, 2026
Educational note: This information is for education only and is not a diagnosis.
Use it to support, not replace, advice from a licensed clinician.
If symptoms are severe, worsening, or urgent, call your local emergency number or seek emergency care.