Differential Diagnosis for Wrist and Arm Pain with Nerve Pain

The patient's symptoms of wrist pain, nerve pain in the arm when bending, and absence of carpal tunnel syndrome in testing, along with a history of repetitive computer strain use, suggest several potential diagnoses. These can be categorized as follows:

• Single Most Likely Diagnosis
  • Repetitive Strain Injury (RSI): This condition is highly plausible given the patient's history of repetitive computer use. RSI can cause pain and discomfort in the wrist, arm, and hand, and can lead to nerve pain due to inflammation and strain on the nerves and tendons.
• Other Likely Diagnoses
  • Thoracic Outlet Syndrome (TOS): This condition 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. It can cause pain in the shoulders and neck and numbness in the fingers, and bending the arm could exacerbate symptoms.
  • Cervical Radiculopathy: This refers to damage or irritation of the nerve roots in the cervical spine, which can cause pain, numbness, and weakness in the neck and arm. Bending the arm could irritate the nerve roots further, leading to pain.
  • Growing Pains: Although more common in children, growing pains could be considered, especially if the patient is in a growth phase. However, the association with repetitive computer use makes this less likely.
• Do Not Miss Diagnoses
  • Pancoast Tumor: A type of lung cancer located at the top of the lung that can cause shoulder and arm pain due to compression of nerves. Although rare, it's crucial to consider due to its severe implications.
  • Multiple Sclerosis: An autoimmune disease that affects the brain and spinal cord, leading to a wide range of potential neurological symptoms, including nerve pain. Early diagnosis is critical for management.
• Rare Diagnoses
  • Complex Regional Pain Syndrome (CRPS): A condition characterized by chronic pain, inflammation, and hypersensitivity in one of the limbs after an injury or trauma. It's less likely but should be considered if other diagnoses are ruled out and symptoms persist.
  • Brachial Plexitis (Neuralgic Amyotrophy): Inflammation of the brachial plexus, which can cause severe pain in the shoulder and arm, followed by weakness and atrophy of the muscles. It's rare and often idiopathic but could be a consideration in the differential diagnosis.

The bent arm with corresponding nerve pain supports the differential diagnosis by indicating that the condition is likely related to the mechanical or positional factors that exacerbate nerve compression or irritation, such as in TOS or cervical radiculopathy. However, a thorough clinical examination, including imaging studies and possibly electromyography (EMG), would be necessary to confirm the diagnosis.