ICD-10-CM > S00-T88 > S40-S49 > S44 > S44.0 > S44.00 S44.00 Injury of ulnar nerve at upper arm level, unspecified arm Non-Billable/Non-Specific Codes S44.00XA..., initial encounterS44.00XD..., subsequent encounterS44.00XS..., sequela