ICD-10-CM > M00-M99 > M80-M85 > M85 > M85.6 > M85.63 M85.63 Other cyst of bone, forearm Non-Billable/Non-Specific Codes M85.631Other cyst of bone, right forearmM85.632Other cyst of bone, left forearmM85.639Other cyst of bone, unspecified forearm