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M87

Non-Billable (Header)

Osteonecrosis

Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)

What This Code Means

M87 is the ICD-10-CM diagnosis code for osteonecrosis. M87 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering other osteopathies (m86-m90).

Header codes like M87 cannot be reported on claims directly — they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at M87's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for M87 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Includes

  • avascular necrosis of bone

Excludes 1 — Do NOT code together

  • juvenile osteonecrosis (M91-M92)
  • osteochondropathies (M90-M93)

Use Additional Code

  • code to identify major osseous defect, if applicable (M89.7-)

Child Codes

Code Hierarchy

M87Osteonecrosis
M87Osteonecrosis

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