M85.029
BillableFibrous dysplasia (monostotic), unspecified upper arm
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M85.029 an HCC code?
No. M85.029 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).
What This Code Means
M85.029 is the ICD-10-CM diagnosis code for fibrous dysplasia (monostotic), unspecified upper arm. Fibrous dysplasia affecting a single bone in the upper arm when the specific side (right or left) is not documented or specified. M85.029 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering disorders of bone density and structure (m80-m85).
M85.029 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.
Use this code only when laterality is not documented in the medical record.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for M85.029 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code only when laterality is not documented in the medical record
- •Attempt to clarify with the provider whether the condition is on the right or left side for more specific coding