Differential Diagnosis for Distal Myopathy with Unilateral Foot Drop
- Single most likely diagnosis
- Charcot-Marie-Tooth disease: A group of inherited disorders that affect the peripheral nerves, leading to distal muscle weakness and atrophy, which can present with unilateral foot drop.
- Other Likely diagnoses
- Peripheral neuropathy: Conditions such as diabetic neuropathy or neuropathy due to other causes (e.g., vitamin deficiencies) can lead to distal weakness and foot drop.
- L5 radiculopathy: Compression or damage to the L5 nerve root can cause weakness and foot drop, typically on one side.
- Distal myopathies (e.g., Welander, Miyoshi, and Udd distal myopathies): A group of inherited myopathies that primarily affect the distal muscles, which can present with unilateral foot drop.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Neoplastic or malignant peripheral nerve sheath tumors: Although rare, these tumors can compress or infiltrate nerves, leading to unilateral foot drop and other neurological symptoms.
- Vasculitic neuropathy (e.g., due to giant cell arteritis or polyarteritis nodosa): Inflammatory conditions that can cause nerve damage and foot drop, which require prompt treatment to prevent further complications.
- Rare diagnoses
- Inclusion body myositis: A rare inflammatory myopathy that can present with distal weakness and foot drop, although it typically affects both sides.
- Focal muscular dystrophy: A rare condition characterized by localized muscle weakness and atrophy, which can present with unilateral foot drop.
- Toxic or drug-induced neuropathy: Certain toxins or medications can cause peripheral neuropathy, leading to distal weakness and foot drop.