Differential Diagnosis for Costoclavicular Syndrome

The costoclavicular syndrome is a condition characterized by compression of the neurovascular bundle between the clavicle and the first rib, leading to a range of symptoms including pain, numbness, and weakness in the arm. The differential diagnosis can be categorized as follows:

• Single Most Likely Diagnosis

  • Thoracic Outlet Syndrome (TOS): This is the most direct and common diagnosis associated with the symptoms of costoclavicular syndrome. TOS involves compression, injury, or irritation of the nerves and/or blood vessels (arteries and veins) in the thoracic outlet area, which lies between your collarbone (clavicle) and first rib. This compression can lead to pain in your shoulders and neck and numbness in your fingers.

• Other Likely Diagnoses

  • Cervical Spondylosis: This condition involves wear and tear on the discs in the neck (cervical spine), which can cause similar symptoms to costoclavicular syndrome, including pain and numbness in the arm.
  • Rotator Cuff Tendinitis: Inflammation of the tendons of the rotator cuff muscles can cause pain and weakness in the shoulder and arm, mimicking some symptoms of costoclavicular syndrome.
  • Brachial Plexitis (Neuralgic Amyotrophy): An inflammatory condition affecting the nerves of the brachial plexus, leading to severe pain and muscle weakness in the shoulder and arm.

• Do Not Miss Diagnoses

  • Subclavian Artery Thrombosis: A blood clot in the subclavian artery can lead to severe arm ischemia and potentially result in gangrene if not promptly treated. Although less common, it's critical due to its potential severity.
  • Subclavian Vein Thrombosis: A clot in the subclavian vein can cause swelling, pain, and discoloration of the arm, and it requires immediate medical attention to prevent long-term complications.
  • Pancoast Tumor: A type of lung cancer located at the top of the lung that can invade the brachial plexus and nearby structures, causing shoulder and arm pain, numbness, and weakness.

• Rare Diagnoses

  • Tumors of the Thoracic Outlet: Rarely, tumors (benign or malignant) in the thoracic outlet can compress the neurovascular bundle, leading to symptoms similar to costoclavicular syndrome.
  • Cervical Rib: An extra rib that can cause compression of the nerves and blood vessels in the thoracic outlet, leading to symptoms of TOS or costoclavicular syndrome.
  • Arteriovenous Fistula: An abnormal connection between an artery and a vein in the thoracic outlet area, which can cause a range of symptoms including arm swelling and pain.

Each of these diagnoses has a different set of implications for treatment and management, emphasizing the importance of a thorough diagnostic evaluation for patients presenting with symptoms of costoclavicular syndrome.