ICD-10-CM > M00-M99 > M80-M85 > M85 > M85.0 > M85.02 M85.02 Fibrous dysplasia (monostotic), upper arm Non-Billable/Non-Specific Codes M85.021Fibrous dysplasia (monostotic), right upper armM85.022Fibrous dysplasia (monostotic), left upper armM85.029Fibrous dysplasia (monostotic), unspecified upper arm