What is thoracic outlet syndrome?
Thoracic outlet syndrome (TOS) occurs when nerves or blood vessels are pinched in the thoracic outlet. The thoracic outlet is the area between your collarbone and your first rib. Nerves and blood vessels run through the thoracic outlet as they go from your chest out to your hands. Compression of these structures can cause pain, tingling, numbness, and weakness in the neck and throughout the arm.
Different types of TOS
- Neurogenic thoracic outlet syndrome (NTOS) occurs when your nerves are pinched. This is the most common type of TOS.
- Vascular thoracic outlet syndrome occurs when your blood vessels are pinched. Vascular TOS is broken into venous or arterial TOS. Venous TOS occurs when veins are pinched. Arterial TOS is a rare type of TOS that occurs when arteries are pinched.
What are the causes?
Thoracic outlet syndrome can be due to soft tissue tightness, restriction in joints, or anatomical variants. Most commonly, tightness in the neck musculature (anterior scalene) and chest (pectoralis minor) will create compression or tension of the neurovascular structures found within the thoracic outlet area. Occasionally, an anatomical variant such as having an extra first rib (cervical rib) will be seen on an x-ray finding. This can also cause a reduction in the space where the vessels and nerves exit into the arm.
Soft-tissue structures can become tight from repetitive injuries such as carrying heavy shoulder loads, poor posture, a previous neck injury (whiplash), or from participating in sports that involve overhead shoulder movements such as tennis, swimming, and weightlifting.
Common symptoms
Thoracic outlet syndrome may include the following symptoms:
- Neck, shoulder, and arm pain
- Numbness/tingling in the shoulder, arm, hand, or fingers
- Impaired circulation to the extremities (causing discoloration)
- Weakness in the shoulder, arm, and hand
Proper diagnosis
Thoracic outlet syndrome can mimic many other conditions; therefore, it is important to receive a comprehensive examination before an accurate diagnosis can be made. Diagnosing thoracic outlet syndrome usually involves:
Patient history
A medical professional will ask about the patient’s medical history, including when and how current symptoms may have started.
Physical exam
The patient is examined for any signs of possible thoracic outlet syndrome such as reduced muscle tone in the thumb or swelling in the arm. Orthopaedic tests will be performed to see if symptoms such as pain, numbness/tingling can be recreated by testing the tight muscular or vasculature in the arm.
Imaging and diagnostic tests
Depending on whether nerve or blood vessel compression is suspected, various forms of imaging and diagnostic tests may be ordered such as an MRI, CT scan, or ultrasound. Also, nerve conduction studies can test how well electrical signals are being transferred through nerves, and electromyography (EMG) can test electrical signals through muscles, which can also pinpoint potential problem spots.
Treatment options
Nonsurgical treatment for thoracic outlet syndrome
There are several forms of treatment for patients with TOS. These may include:
- Manual therapy with careful nerve stretching movements performed by a qualified and experienced doctor or therapist with experience in treating TOS.
- Mobilization of the first cervical rib to eliminate any joint restrictions.
- Myofascial release or dry needling techniques to reduce tight musculature that might be causing the compression.
- Injections with nerve blocking agents to suppress pain and reduce swelling and compression.
- Nonsteroidal anti-inflammatory (NSAID) medicine, muscle relaxants or pain medication to decrease swelling or pain.
Surgery for thoracic outlet syndrome (TOS)
If nonsurgical treatments do not provide relief or if the health of a nerve or blood vessel is at risk, surgery may be advised. Various types of surgery are possible and will depend on the location of the compression, as well as what is being compressed.
How can I help manage my symptoms?
- Make sure you practice correct posture.
- Try not to sleep with your arms over your head or chest.
- Avoid activities that involve repetitive movements.
- Do exercises as directed to strengthen and stretch your shoulder and neck muscles.
When should I contact my doctor?
You should make sure to contact your doctor or therapist if you are experiencing new pain, numbness, or tingling in your neck, shoulder, arm, or hand. Also, if you have a weak grip and this is new for you, or you notice that one hand looks smaller than the other.