ICD-10 Code G56.9 – Unspecified Mononeuropathy of Upper Limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G56.9 – Unspecified mononeuropathy of upper limb
What it is
This code identifies a single nerve disorder affecting the upper limb when the specific nerve is not documented. It is used for neuropathic conditions of the arm or hand that are not otherwise classified.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include numbness, tingling, pain, weakness, or sensory loss in a distribution consistent with one upper-extremity nerve.
When to use this code
Use G56.9 when the record supports mononeuropathy in the upper limb but does not name the affected nerve. It is appropriate when the provider documents an unspecified nerve lesion, neuropathy, or entrapment without further detail. Check documentation if laterality or etiology is needed.
Do not use for
Do not use this code for polyneuropathy, radiculopathy, or generalized peripheral neuropathy. If a specific upper-limb nerve is identified, code that more precise diagnosis instead.
Coding tip
Query for the exact nerve involved before defaulting to G56.9.