What is thoracic outlet syndrome?

Thoracic outlet syndrome (TOS) is a medical condition that causes pain in the shoulder, arm, and neck area. This syndrome occurs when the nerves or blood vessels located just below the neck are subjected to pressure or compression. This compression can occur between the muscles of the neck and shoulder, or between the first rib and the collarbone [2].

Causes of thoracic outlet syndrome

There are many causes that may lead to thoracic outlet syndrome, including:

• Injuries: Such as those resulting from car accidents or falls, which may lead to changes in the structure of the area and cause pressure on the nerves or blood vessels [2].
• Anatomical defects: Some people may be born with anatomical defects that increase the risk of injury, such as the presence of an extra rib (cervical rib) or abnormal muscle structures [2].
• Tumors: In rare cases, tumors may press on the nerves or blood vessels in the thoracic outlet area [2].
• Poor posture: Maintaining poor posture consistently, especially in the neck and shoulders, can contribute to nerve compression [2].
• Pregnancy: Hormonal and physical changes during pregnancy can lead to the worsening or onset of symptoms of thoracic outlet syndrome [2].
• Repetitive movements: Activities that involve repetitive movements of the arm and shoulder, such as certain types of sports or professions, may increase the risk of injury [2].

Common symptoms

Symptoms vary based on whether nerves or blood vessels are affected:

• If a nerve is compressed: The patient may feel burning, numbness, and tingling along the arm, hand, and fingers. They may also suffer from weakness in the hand [2].
• If a vein is compressed: The hand may become sensitive to cold, or its color may change to pale or bluish. The arm may become swollen and tire easily [2].

Thoracic outlet syndrome is more common in women, and symptoms usually begin to appear between the ages of 20 and 50 [2].

Diagnosis of thoracic outlet syndrome

To diagnose thoracic outlet syndrome, doctors rely on a set of tests, including:

• Clinical examination: This involves evaluating symptoms, medical history, and performing specific maneuvers to check for compression.
• Nerve and imaging studies: Such as nerve conduction studies (Arabic) and electromyography (EMG). Nerve conduction studies measure the speed and strength of electrical signals traveling through the nerves, as damaged nerves can indicate a slower and weaker signal. Electromyography measures the electrical activity of muscles at rest and during movement [1]. These tests help determine whether the symptoms are caused by a muscle or nerve problem [1].
• Imaging tests: These may include X-rays, MRI, or ultrasound to evaluate the structure of the area and rule out other causes of the symptoms [2].

It is important to consult a doctor when any of the mentioned symptoms appear to evaluate the condition accurately and determine an appropriate treatment plan. Early diagnosis contributes to improving outcomes and recovery.

Medical references

• Thoracic Outlet Syndrome
• Electromyography (EMG) and Nerve Conduction Studies