Understanding the condition
Thoracic outlet syndrome (TOS) describes compression of nerves or blood vessels as they pass from the lower neck into the arm. Neurogenic TOS affects the brachial plexus. Venous and arterial TOS involve blood vessels and require different assessment and treatment pathways.
What might you notice?
- Pain, tingling, numbness or heaviness in the arm or hand.
- Symptoms that worsen with overhead activity or sustained arm positions.
- Arm fatigue or weakness affecting work, exercise or daily activities.
These symptoms can have more than one cause. A clinical assessment is needed to establish the diagnosis.
Specialist assessment
There is no single test that establishes or excludes neurogenic TOS in every patient. Assessment includes the neck, shoulder and upper limb, with targeted investigations where appropriate. Normal routine tests do not automatically exclude TOS, but other explanations must be considered.
Your treatment options
Treatment commonly starts with specialist physiotherapy, changes to activity and support for pain management. Decompression surgery may be considered for selected patients with persistent disabling symptoms or progressive neurological findings. The operation is tailored to the structures involved, and symptom resolution cannot be guaranteed.
Common questions
Can my nerve tests be normal?
Yes. Routine investigations may be normal in neurogenic TOS. Results need to be interpreted alongside the history, examination and possible alternative diagnoses.
Is surgery always required?
No. Many patients begin with structured physiotherapy and activity modification. Surgery requires careful selection and a discussion of benefits, limitations and risks.
General patient information from London Nerve Injury. Decisions about investigations and treatment require an individual clinical assessment.