ICD-10-CM > M00-M99 > M20-M25 > M21 > M21.8 > M21.83 M21.83 Other specified acquired deformities of forearm Non-Billable/Non-Specific Codes M21.831Other specified acquired deformities of right forearmM21.832Other specified acquired deformities of left forearmM21.839Other specified acquired deformities of unspecified forearm