ICD-10-CM > S00-T88 > S50-S59 > S54 > S54.9 > S54.90 S54.90 Injury of unspecified nerve at forearm level, unspecified arm Non-Billable/Non-Specific Codes S54.90XA..., initial encounterS54.90XD..., subsequent encounterS54.90XS..., sequela