Differential Diagnosis
The patient presents with atraumatic, burning right upper discomfort to the shoulder, back of the shoulder, and associated symptoms. Here's a categorized differential diagnosis:
Single most likely diagnosis
- Subacromial bursitis or rotator cuff tendinitis: The patient's symptoms of burning discomfort in the shoulder, exacerbated by lateral movements and adduction, are consistent with inflammation of the subacromial bursa or rotator cuff tendinitis. The hot feeling down the lateral side of her arm could be referred pain from the shoulder.
Other Likely diagnoses
- Adhesive capsulitis (frozen shoulder): This condition can cause shoulder pain and stiffness, especially with movements like adduction. The pain can radiate down the arm.
- Cervical radiculopathy: The patient's symptoms of neck pain and hot feeling down the arm could be indicative of a cervical nerve root impingement, which can cause radiating pain and sensations.
- Brachial plexus strain: This can cause pain and sensations in the shoulder, neck, and arm, especially with movements that stretch the plexus.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Pulmonary embolism: Although less likely, a pulmonary embolism can cause sudden onset of shoulder pain, especially if the embolism is large and causes pulmonary infarction. The pain can be referred to the shoulder due to irritation of the diaphragm.
- Myocardial infarction (MI): MI can cause referred pain to the shoulder, neck, and arm, especially in women. It's essential to consider cardiac causes, especially if the patient has risk factors.
- Spinal cord injury or compression: Although rare, spinal cord compression or injury can cause pain, numbness, and weakness in the arm and neck.
Rare diagnoses
- Thoracic outlet syndrome: This condition can cause pain, numbness, and tingling in the arm and neck due to compression of the brachial plexus or subclavian artery.
- Pancoast tumor: A rare type of lung cancer that can cause shoulder pain, especially if it invades the brachial plexus or nearby structures.
- Referred pain from abdominal or pelvic pathology: Rarely, abdominal or pelvic conditions like gallbladder disease or ovarian cysts can cause referred pain to the shoulder and arm.