ICD-10 Code G56.23 – Lesion of ulnar nerve, bilateral upper limbs (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G56.23 – Lesion of ulnar nerve, bilateral upper limbs
What it is
G56.23 identifies a disorder affecting both ulnar nerves in the upper limbs. Use it when documentation states a lesion, injury, or dysfunction of the ulnar nerve on both sides.
Clinical signs
Typical findings include numbness or tingling in the ring and little fingers, hand weakness, and reduced grip strength. Clinical features vary; refer to documentation for laterality and nerve involvement.
When to use this code
Use this code when the provider documents bilateral ulnar nerve lesion, compression, or neuropathy limited to both upper limbs. It fits cases where both sides are clearly identified in the assessment. If the record only mentions one side, do not assume bilateral involvement.
Do not use for
Do not use it for unspecified ulnar nerve disorders or conditions involving only one arm. Check documentation if the problem is better described as another neuropathy or a different nerve lesion.
Coding tip
Confirm bilateral wording in the note and code the laterality exactly as documented.