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, and the most effective approach to managing TOS involves a combination of physical therapy, pain management, and lifestyle modifications, with surgery reserved for severe cases that do not respond to conservative treatment 1.
Understanding Thoracic Outlet Syndrome
TOS can be classified into three main types: neurogenic (affecting nerves), venous (affecting veins), and arterial (affecting arteries), with neurogenic being the most common. Symptoms typically include:
- Pain, numbness, tingling in the neck, shoulder, arm or hand
- Weakness in the hand
- Discoloration or swelling in the arm TOS is often caused by physical trauma, repetitive arm or shoulder movements, anatomical abnormalities like an extra rib, or poor posture.
Diagnosis and Treatment
Diagnosis involves physical examination, imaging tests like X-rays or MRIs, and nerve conduction studies. Treatment usually begins conservatively with:
- Physical therapy to strengthen chest muscles and improve posture
- Pain medication like NSAIDs
- Activity modifications For severe cases not responding to conservative treatment, surgery may be necessary to remove the first rib or repair compressed blood vessels 1. Prevention strategies include:
- Maintaining good posture
- Taking breaks during repetitive activities
- Strengthening shoulder muscles
- Avoiding carrying heavy bags on your shoulders
Imaging and Radiological Evaluation
Imaging tests such as CT, MRI, and ultrasound can be used to evaluate the thoracic outlet and diagnose TOS. MRI is typically performed with high-resolution T1-weighted and T2-weighted sequences in sagittal and axial planes to delineate anatomy and evaluate cervical radiculopathy, the brachial plexus, muscular attachments, and sites of compression 1. CT evaluation of TOS is typically performed in “neutral” and “stressed” positions, with images obtained from the elbow to aortic arch with the arms adducted (neutral), followed by abduction (stressed) and repeat imaging 1.
From the Research
Definition and Classification of Thoracic Outlet Syndrome
- Thoracic outlet syndrome (TOS) is a condition caused by compression of the neurovascular structures leading to the arm passing through the thoracic outlet 2.
- TOS can be classified as neurogenic, arterial, or venous based on the compressed structure(s) 3.
- Neurogenic TOS is the most common type, accounting for 95% of cases, while venous and arterial TOS account for 4-5% and 1% of cases, respectively 2.
Causes and Risk Factors
- TOS can be caused by congenital abnormalities, such as cervical ribs or fibrous bands originating from a cervical rib 3.
- Neck trauma or repeated work stress can cause scalene muscle scaring or dislodging of a congenital cervical rib, leading to compression of the brachial plexus 3.
- Anatomical variations, such as hypertrophy of the neck musculature, can also contribute to TOS 4.
- Other risk factors include abrupt movements, edema, pregnancy, repeated overhead motions, and abnormal posture 4.
Symptoms and Diagnosis
- Patients with TOS typically experience upper limb pain, numbness, tingling, or weakness that is exacerbated by shoulder or neck movement 4.
- Diagnosis of TOS can be established through history, physical examination maneuvers, and imaging 3.
- Diagnostic tests may include duplex ultrasonography to detect thrombosis in arterial or venous TOS 2.
Treatment Options
- Conservative management of TOS includes postural correction, stretching exercises, and strengthening exercises of the lower scapular stabilizers 5, 6.
- Nonsurgical treatment may also include anti-inflammatory medication, weight loss, physical therapy, and botulinum toxin injections 3.
- Surgical treatment options include brachial plexus decompression, neurolysis, and scalenotomy with or without first rib resection 3, 2.
- A multidisciplinary approach is recommended for proper treatment of TOS, regardless of the type encountered 2.