Differential Diagnosis for Shoulder Pain Radiating to the Axilla and Arm and Forearm
Single Most Likely Diagnosis
- Subacromial Bursitis or Rotator Cuff Tendinitis: These conditions are common causes of shoulder pain that can radiate down the arm due to inflammation of the bursae or tendons around the shoulder joint. The pain pattern and the involvement of the axilla and arm are consistent with these diagnoses, especially if there's a history of overuse or trauma.
Other Likely Diagnoses
- Adhesive Capsulitis (Frozen Shoulder): Characterized by pain and stiffness in the shoulder, which can radiate to the arm. It often results from inflammation and scarring of the tissues surrounding the shoulder joint.
- Cervical Radiculopathy: Refers to damage or irritation of the nerve roots in the cervical spine, which can cause pain radiating from the neck down to the shoulder, arm, and forearm, depending on the nerve root affected.
- Thoracic Outlet Syndrome: Involves compression of the nerves and/or blood vessels that pass into the thoracic outlet (the space between your collarbone and first rib), leading to pain in the shoulder, arm, and forearm.
Do Not Miss Diagnoses
- Myocardial Infarction (Heart Attack): Although less common, myocardial infarction can present with referred pain to the shoulder, arm, and forearm, especially in women. It's crucial to consider this diagnosis, especially if accompanied by other symptoms like chest pain, shortness of breath, or nausea.
- Pulmonary Embolism: Can cause sudden onset of shoulder pain due to referred pain from the diaphragm, especially if the embolism involves the lung's lower lobes.
- Spinal Cord Injury or Compression: Conditions like spinal stenosis, herniated discs, or spinal fractures can compress the spinal cord, leading to pain, numbness, and weakness in the arms and forearms.
Rare Diagnoses
- Pancoast Tumor: A type of lung cancer located at the top of the lung that can cause shoulder pain radiating to the arm due to invasion of the brachial plexus.
- Brachial Plexitis (Neuralgic Amyotrophy): An inflammatory condition affecting the brachial plexus, leading to severe pain in the shoulder and arm, followed by weakness and atrophy of the muscles.
- Osteonecrosis of the Humeral Head: A condition where the blood supply to the humeral head is interrupted, leading to bone death and potentially causing shoulder pain that can radiate down the arm.