ICD-10-CM > S00-T88 > S50-S59 > S56 > S56.9 > S56.91 S56.91 Strain of unspecified muscles, fascia and tendons at forearm level Non-Billable/Non-Specific Codes S56.911Strain of unspecified muscles, fascia and tendons at forearm level, right armS56.911A..., initial encounterS56.911D..., subsequent encounterS56.911S..., sequelaS56.912Strain of unspecified muscles, fascia and tendons at forearm level, left armS56.912A..., initial encounterS56.912D..., subsequent encounterS56.912S..., sequelaS56.919Strain of unspecified muscles, fascia and tendons at forearm level, unspecified armS56.919A..., initial encounterS56.919D..., subsequent encounterS56.919S..., sequela