Fibrous dysplasia (monostotic), right upper arm

This code identifies a benign, localized bone disorder characterized by the replacement of normal bone with fibrous tissue and immature woven bone. Specifically, it indicates fibrous dysplasia affecting only one bone (monostotic) located in the patient's right upper arm. This condition can lead to bone weakness, pain, and deformity.

Use this code for patients diagnosed with monostotic fibrous dysplasia confirmed to be present in the right humerus. Documentation should clearly specify the monostotic nature of the lesion and its anatomical location in the right upper arm, typically supported by imaging studies (e.g., X-ray, MRI) and/or biopsy results.

• Ensure documentation specifies "monostotic" to differentiate from polyostotic forms (M85.00-M85.09).
• Verify laterality (right vs. left) and the specific bone involved within the upper arm.
• Do not use for McCune-Albright syndrome, which involves polyostotic fibrous dysplasia and endocrine abnormalities.