Neurogenic Thoracic Outlet Syndrome

Neurogenic thoracic outlet syndrome (TOS) is a condition involving the compression of the brachial plexus, a network of nerves responsible for transmitting signals from the spinal cord to the shoulder, arm, and hand.

This compression can lead to a variety of symptoms, such as pain, weakness, and numbness in the affected arm and hand.

Neurogenic TOS is caused by several factors, including anatomical abnormalities, trauma, poor posture, and repetitive strain.

Accurate diagnosis through medical history, physical examination, and imaging tests is crucial for effective treatment, which may involve physical therapy, medications, injections, or, in severe cases, surgery.

What is neurogenic thoracic outlet syndrome?

Neurogenic thoracic outlet syndrome is the most common type of TOS, accounting for approximately 95% of all TOS cases.

It occurs when there is compression of the brachial plexus, a network of nerves that send signals from the spinal cord to the shoulder, arm, and hand. This compression can lead to pain, weakness, and numbness in the affected arm and hand.

Learn more: What is thoracic outlet syndrome?

Neurogenic TOS causes

Several factors can contribute to the development of neurogenic TOS, including:

Anatomical abnormalities

• Cervical ribs: Extra ribs arising from the cervical spine can compress the brachial plexus.
• Fibromuscular bands: Tight bands of muscle or ligament can compress nerves.
• Congenital defects: Inherited abnormalities in bone structure or muscle arrangement.

Trauma

• Injuries: Trauma from accidents or falls can lead to neurogenic TOS by causing swelling or hematoma that presses on nerves.
• Repetitive strain: Activities requiring repeated overhead use, such as certain sports or occupations, can contribute to neurogenic TOS.

Poor posture

• Slouching: Poor posture, especially drooping shoulders and forward head posture, can place stress on the thoracic outlet region.
• Prolonged postures: Long periods of sitting or holding arms in certain positions can exacerbate nerve compression.

Other factors

• Tumors: Rarely, tumors or growths in the thoracic outlet can compress the brachial plexus.
• Obesity: Excess weight can increase pressure on the thoracic outlet.

Neurogenic TOS symptoms

Symptoms of neurogenic TOS can vary but often include the following:

Sensory symptoms

• Numbness: Tingling or numbness in the arm, hand, or fingers.
• Pain: Aching or burning pain in the shoulder, arm, or neck.

Motor symptoms

• Weakness: Weakness in the arm or fingers, leading to difficulty with grasping or fine motor skills.
• Muscle atrophy: Severe cases may cause muscle wasting in the hand or arm.

Other symptoms

• Heaviness: Sensation of heaviness or fatigue in the arm.
• Swelling: Swelling of the arm, particularly with excessive use.

Neurogenic TOS diagnosis

Diagnosing neurogenic TOS involves a thorough medical evaluation, including:

Medical history

Your doctor will ask detailed questions about your symptoms, medical history, and activities that may contribute to neurogenic TOS.

Physical examination

A physical exam will assess the range of motion, strength, and areas of pain or numbness. Specific maneuvers may be performed to reproduce symptoms and pinpoint the area of compression.

Imaging tests

Imaging tests may include:

• X-rays: To check for cervical ribs or other bone anomalies.
• MRI: To visualize soft tissue structures and nerve compression.
• CT scans: For detailed images of bone and tissue abnormalities.

Nerve conduction studies and electromyography (EMG)

These tests evaluate the electrical activity in muscles and the speed of nerve signal transmission to help diagnose nerve compression.

Provocative tests

Special tests that provoke symptoms, such as the Adson’s test or Roos test, may be used to identify neurogenic TOS.

Neurogenic TOS treatment

Treatment for neurogenic TOS can vary based on severity and underlying causes. Common approaches include:

Conservative treatments

• Physical therapy: Designed to strengthen and stretch muscles, improve posture, and relieve nerve compression.
• Medications: Anti-inflammatory drugs or pain relief medications to manage symptoms.
• Lifestyle changes: Ergonomic adjustments and avoiding activities that exacerbate symptoms.

Injection therapy

• Botulinum toxin injections: To relax muscles contributing to compression.
• Steroid injections: To reduce inflammation and swelling.

Surgical treatment

If conservative treatments are ineffective, surgery may be considered. Surgical options include:

• Resection of cervical ribs: Removal of extra ribs causing compression.
• Scalenectomy: Removal of portions of the scalene muscles to relieve nerve pressure.
• Thoracic outlet decompression: Procedures to remove fibromuscular bands or other structures compressing nerves.

Living with neurogenic TOS

Managing neurogenic TOS requires a multi-faceted approach involving medical intervention, therapy, and lifestyle modifications. Staying active and maintaining good posture are vital.

Early diagnosis and treatment significantly improve outcomes, allowing individuals to return to normal activities with reduced symptoms.

If you suspect you have neurogenic TOS or have been diagnosed with the condition, it is essential to seek medical advice from a health care professional. With appropriate treatment and management, symptoms can be effectively controlled, enhancing your quality of life.