ICD-10-CM > S00-T88 > S50-S59 > S56 > S56.9 > S56.91 > S56.912 S56.912 Strain of unspecified muscles, fascia and tendons at forearm level, left arm Non-Billable/Non-Specific Codes S56.912A..., initial encounterS56.912D..., subsequent encounterS56.912S..., sequela