ICD-10-CM > S00-T88 > S40-S49 > S44 > S44.4 > S44.40 S44.40 Injury of musculocutaneous nerve, unspecified arm Non-Billable/Non-Specific Codes S44.40XA..., initial encounterS44.40XD..., subsequent encounterS44.40XS..., sequela