ICD-10 Code G57.8 – Other specified mononeuropathies of lower limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G57.8 – Other specified mononeuropathies of lower limb
What it is
This code identifies a single nerve disorder in the lower limb that does not fit a more specific ICD-10 category. Use it when documentation names an unspecified or other named mononeuropathy affecting the leg or foot.
Clinical signs
Findings usually reflect dysfunction of one peripheral nerve, such as localized pain, numbness, tingling, weakness, or sensory loss in a nerve distribution. Clinical features vary; refer to documentation.
When to use this code
Use G57.8 when the provider documents a lower-limb mononeuropathy that is not captured by a more specific code, such as a named nerve disorder outside the listed categories. It may also apply when the record states “other specified” mononeuropathy and the affected site is the leg or foot. Check documentation if the nerve or exact type is unclear.
Do not use for
Do not use this code for generalized polyneuropathy, radiculopathy, or nerve disorders of the upper limb. If the documentation supports a more specific lower-limb mononeuropathy, code that diagnosis instead.
Coding tip
Confirm the exact nerve and laterality in the note, and choose G57.8 only when no more specific lower-limb mononeuropathy code applies.