Differential Diagnosis
- Single most likely diagnosis
- Cubital Tunnel Syndrome: This condition is the most likely diagnosis given the patient's symptoms of pain in the forearm and little finger, numbness in the little finger, weakness of grip, and decreased sensation to light touch at the tip of the little finger. The paresthesias elicited with compression of the cubital tunnel further support this diagnosis, as cubital tunnel syndrome involves compression of the ulnar nerve at the elbow.
- Other Likely diagnoses
- Ulnar Neuropathy: This could be considered if the symptoms are not exclusively related to compression at the cubital tunnel but still involve the ulnar nerve distribution. It might not fully explain the specific elicitation of paresthesias with cubital tunnel compression but is a broader category that includes cubital tunnel syndrome.
- C8 Radiculopathy: This condition involves the nerve root at the C8 level and could present with similar symptoms, including pain, numbness, and weakness in the hand, particularly affecting the little finger. However, it might not as directly correlate with the specific finding of paresthesias upon cubital tunnel compression.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Pancoast Tumor: Although rare, a Pancoast tumor (a type of lung cancer located at the apex of the lung) can cause ulnar nerve symptoms by invading or compressing the brachial plexus. It's crucial to consider this in the differential diagnosis due to its severe implications and the need for early detection.
- Brachial Plexus Injury or Tumor: Any condition affecting the brachial plexus could potentially cause the symptoms described. While less common, these conditions can have significant consequences and should not be overlooked.
- Rare diagnoses
- Thoracic Outlet Syndrome: This condition involves compression of the nerves and/or blood vessels that pass into the thoracic outlet (the space between your collarbone and first rib). It could potentially cause similar symptoms but is less likely given the specific distribution of symptoms and the elicitation of paresthesias with cubital tunnel compression.
- Multifocal Motor Neuropathy: A rare condition characterized by asymmetric muscle wasting and weakness, it could potentially mimic some of the symptoms but is much less common and would typically have a more widespread presentation.