Differential Diagnosis for Numbness over the Left Ulnar Nerve Distribution of the Hand after a Fall
Single Most Likely Diagnosis
- Ulnar nerve injury or contusion: This is the most likely diagnosis given the direct trauma to the arm or elbow during the fall, which can cause damage to the ulnar nerve, leading to numbness in its distribution area.
Other Likely Diagnoses
- Fracture of the elbow or wrist: A fracture in the elbow or wrist area could compress or damage the ulnar nerve, causing numbness.
- Cubital tunnel syndrome: This condition, where the ulnar nerve is compressed at the elbow, could be exacerbated by a fall, leading to symptoms.
- Radial head fracture or dislocation: Although less directly related to ulnar nerve distribution, significant trauma to the elbow can cause multiple injuries, including those affecting the radial head, which might indirectly affect ulnar nerve function or cause referred symptoms.
Do Not Miss Diagnoses
- Brachial plexus injury: A severe injury that could result from a significant fall, potentially affecting multiple nerves and leading to widespread numbness, weakness, or paralysis in the arm.
- Vascular injury: Damage to the blood vessels supplying the arm could lead to ischemia, causing numbness, pain, and potentially gangrene if not promptly addressed.
- Spinal cord injury: Although less likely given the specific distribution of numbness, a spinal cord injury could result from a fall and might present with numbness in a dermatomal pattern, including potentially the ulnar nerve distribution.
Rare Diagnoses
- Tumor or cyst compressing the ulnar nerve: Pre-existing conditions that could be exacerbated by a fall, leading to increased pressure on the ulnar nerve.
- Infection or abscess: Although rare, an infection in the vicinity of the ulnar nerve could cause inflammation and compression, leading to numbness.
- Diabetic neuropathy or other systemic neuropathies: In patients with underlying conditions like diabetes, a fall might not be directly related to the onset of neuropathic symptoms, but the timing could coincide, leading to a complex diagnostic picture.