From the Guidelines
Thoracic Outlet Syndrome (TOS) is a condition where blood vessels or nerves in the space between your collarbone and first rib (thoracic outlet) become compressed, causing pain in your shoulders and neck and numbness in your fingers. This condition occurs when the nerves, arteries, or veins passing through the thoracic outlet become compressed due to anatomical abnormalities, poor posture, trauma, or repetitive movements 1. The compression can occur in three distinct spaces: the costoclavicular triangle, the interscalene triangle, and the pectoralis minor space, each with different presentations and symptoms 1.
Causes and Risk Factors
The causes of TOS include anatomical abnormalities, such as a cervical rib or anomalous first rib, poor posture, trauma, or repetitive movements 1. Patients who perform activities that require repetitive upper-extremity movement, such as swimming or throwing, are at higher risk of developing TOS 1.
Symptoms and Diagnosis
Symptoms of TOS include chronic arm and hand paresthesia, numbness, or weakness, as well as pain in the shoulders and neck 1. Diagnosis of TOS can be made using imaging studies such as CT or MRI, which can help identify anatomical narrowing and compression of the neurovascular structures 1.
Treatment and Management
Treatment of TOS typically begins with physical therapy focusing on stretching and strengthening exercises to open the thoracic outlet, improve posture, and strengthen supporting muscles. For pain management, NSAIDs like ibuprofen (400-800mg three times daily) or naproxen (250-500mg twice daily) can be used 1. Muscle relaxants such as cyclobenzaprine (5-10mg three times daily) may help with associated muscle spasms 1. In more severe cases, a scalene muscle block with lidocaine or botulinum toxin injections might be considered 1. Surgery is reserved for cases with significant vascular compromise or persistent neurological symptoms despite conservative treatment 1.
Prevention and Lifestyle Modifications
Patients should avoid activities that worsen symptoms, maintain good posture, take frequent breaks from repetitive tasks, and follow through with prescribed physical therapy exercises for the best outcomes 1. By understanding the causes and symptoms of TOS, patients can take steps to prevent and manage the condition, improving their quality of life and reducing morbidity and mortality.
From the Research
Definition and Classification of Thoracic Outlet Syndrome (TOS)
- Thoracic outlet syndrome (TOS) is a rare condition caused by neurovascular compression at the thoracic outlet, presenting with arm pain and swelling, arm fatigue, paresthesias, weakness, and discoloration of the hand 2.
- TOS can be classified as neurogenic, arterial, or venous based on the compressed structure(s) 2, 3.
- The diagnosis of TOS is often made in the presence of symptoms with physical examination findings, and it is not a diagnosis of exclusion 2.
Causes and Risk Factors of TOS
- Patients develop TOS secondary to congenital abnormalities such as cervical ribs or fibrous bands originating from a cervical rib leading to an objectively verifiable form of TOS 2.
- Neck trauma or repeated work stress can cause scalene muscle scaring or dislodging of a congenital cervical rib that can compress the brachial plexus 2.
- Postural deviations can contribute substantially to compression of the thoracic outlet 4.
Symptoms and Diagnosis of TOS
- TOS is a symptom complex attributed to compression of the nerves and vessels as they exit the thoracic outlet 4, 5.
- The diagnosis is based mainly on the findings of the history and physical examination 5, 6.
- Diagnostic tests and treatment options for TOS include history, physical examination maneuvers, and imaging 2.
Treatment Options for TOS
- Nonsurgical treatment includes anti-inflammatory medication, weight loss, physical therapy/strengthening exercises, and botulinum toxin injections 2.
- Conservative management is generally recommended as the first stage treatment in favor of surgical intervention 4, 5, 6.
- Surgical treatment options include brachial plexus decompression, neurolysis, and scalenotomy with or without first rib resection 2, 3.
- Patients undergoing surgical treatment for TOS should be seen postoperatively to begin passive/assisted mobilization of the shoulder 2.