Utilization Review Checklist
Ulnar Nerve Entrapment at the Wrist
Derived from the ACOEM Hand, Wrist and Forearm Disorders Guideline, edition 14 July 2025, as adopted into the California MTUS 2 January 2026. CPT 64718, 64719, 64721. ICD-10 G56.2.
Draft — not reviewed or approved by COA. Prepared by Rette from the ACOEM guideline named above. This is not a COA document and does not reproduce COA’s own checklists.
CriteriaCheck if documented
Confirmatory Diagnosis
Required
Subacute or chronic ulnar nerve compression at the wrist
“Surgical decompression is recommended for subacute or chronic ulnar nerve compression at the wrist after failure of non-operative treatment or if space-occupying lesions are present.” — p. 426
Conservative Care
Any one of the following
Failure of non-operative treatment
“after failure of non-operative treatment” — p. 426
OR
A space-occupying lesion is present
“or if space-occupying lesions are present.” — p. 426
Surgical Considerations (surgical decompression)
Required
Decompression requested at the wrist
“Surgical decompression is recommended for subacute or chronic ulnar nerve compression at the wrist after failure of non-operative treatment or if space-occupying lesions are present.” — p. 426
Procedures — the guideline treats each separately
Surgical decompression for ulnar nerve compression at the wrist
Recommended.
Strength of Evidence — Recommended, Insufficient Evidence (I) · confidence moderate
Two alternative routes and either is enough: failure of non-operative treatment, OR the presence of a space-occupying lesion. A demonstrated lesion — a ganglion in Guyon's canal is the classic — reaches surgery without a conservative trial, so image the canal and say what is there.