M87.850
BillableOther osteonecrosis, pelvis
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M87.850 an HCC code?
Yes. M87.850 maps to Bone/Joint/Muscle Infections/Necrosis under the CMS-HCC V28 risk adjustment model (and Bone/Joint/Muscle Infections/Necrosis under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for M87.850
For M87.850 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed M87.850 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M87.850 is the ICD-10-CM diagnosis code for other osteonecrosis, pelvis. Death of bone tissue in the pelvis due to loss of blood supply, affecting the hip bone structure. M87.850 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).
Under the CMS-HCC V28 risk adjustment model, M87.850 maps to Bone/Joint/Muscle Infections/Necrosis (HCC 92) with a community, non-dual, aged base RAF weight of 0.209. Under the older V24 model, M87.850 mapped to the same category but with a base RAF weight of 0.482 — V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Pelvic osteonecrosis is less common; ensure documentation clearly indicates pelvic involvement rather than femoral head. Because M87.850 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for M87.850 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Pelvic osteonecrosis is less common; ensure documentation clearly indicates pelvic involvement rather than femoral head
- •Consider associated conditions like sickle cell disease or prolonged corticosteroid use
Clinical Significance
Osteonecrosis of the pelvis represents a serious condition affecting the hip bones and potentially compromising weight-bearing function and mobility. This diagnosis has significant risk adjustment implications due to the complex care requirements, potential need for major surgical intervention, and impact on ambulation and quality of life.
Documentation Requirements
- ✓Specific identification of pelvic bone involvement in osteonecrosis
- ✓Documentation of causes other than idiopathic or drug-induced osteonecrosis
- ✓Advanced imaging (MRI, CT, bone scan) confirming pelvic bone necrosis
- ✓Clinical presentation including pelvic pain, hip dysfunction, and mobility limitations
- ✓Exclusion of infectious or traumatic causes as primary etiology
- ✓Assessment of impact on weight-bearing capacity and ambulation
- ✓Documentation of any underlying conditions or risk factors
- ✓Provider evaluation of treatment complexity and surgical considerations