ICD-10 Code G56.12 – Other lesions of median nerve, left upper limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G56.12 – Other lesions of median nerve, left upper limb
What it is
Use this code for a documented nontraumatic disorder or lesion of the median nerve in the left upper limb when the exact condition is not otherwise specified. It identifies the left-sided nerve problem, not a wrist or hand diagnosis by itself.
Clinical signs
Findings may include numbness, tingling, pain, or weakness in a median-nerve distribution on the left. Clinical features vary; refer to documentation and any exam or nerve study results that support median nerve involvement.
When to use this code
Assign this code when the provider documents an other lesion, neuropathy, or disorder of the left median nerve without a more specific diagnosis. Use it for left-sided median nerve involvement that is not better captured by carpal tunnel syndrome or another defined condition.
It is appropriate when the record clearly states the median nerve is affected in the left upper limb and no alternate etiology is documented. Check documentation if the note only describes hand pain, paresthesia, or weakness without naming the nerve.
Do not use for
Do not use this code for traumatic nerve injury, carpal tunnel syndrome, or symptoms without a documented median nerve lesion. If the condition is bilateral or on the right, choose the matching code instead.
Coding tip
Verify laterality and the exact nerve named in the assessment before coding.