ICD-10-CM > M00-M99 > M65-M67 > M65 > M65.8 > M65.83 M65.83 Other synovitis and tenosynovitis, forearm Non-Billable/Non-Specific Codes M65.831Other synovitis and tenosynovitis, right forearmM65.832Other synovitis and tenosynovitis, left forearmM65.839Other synovitis and tenosynovitis, unspecified forearm