M85.9
BillableDisorder of bone density and structure, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M85.9 an HCC code?
No. M85.9 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
M85.9 is the ICD-10-CM diagnosis code for disorder of bone density and structure, unspecified. A general condition affecting bone density and structure that cannot be more specifically identified, such as abnormal bone thickness or composition. M85.9 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).
M85.9 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 the specific bone density disorder cannot be determined from documentation.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for M85.9 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 the specific bone density disorder cannot be determined from documentation
- •Review clinical notes for more specific diagnoses like osteoporosis or osteosclerosis before assigning this unspecified code