M87.044
BillableIdiopathic aseptic necrosis of right finger(s)
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M87.044 an HCC code?
Yes. M87.044 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 M87.044
For M87.044 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 M87.044 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M87.044 is the ICD-10-CM diagnosis code for idiopathic aseptic necrosis of right finger(s). Death of bone tissue in the right finger(s) without infection, occurring without a known cause. M87.044 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, M87.044 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, M87.044 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.
This code is specific to right-sided finger involvement; verify which fingers are affected in documentation. Because M87.044 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 M87.044 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code is specific to right-sided finger involvement; verify which fingers are affected in documentation
- •If multiple fingers are involved, this single code covers all right fingers affected
Clinical Significance
Idiopathic aseptic necrosis of right finger(s) represents bone death in phalangeal bones without identifiable cause, potentially affecting fine motor function and hand dexterity. This condition can significantly impact activities requiring precise finger movement and may require surgical intervention to preserve finger function and prevent joint collapse.
Documentation Requirements
- ✓Documentation of aseptic necrosis specifically affecting right finger bones
- ✓Confirmation of idiopathic etiology with no underlying cause identified
- ✓Imaging evidence demonstrating bone necrosis in right finger phalanges
- ✓Clear laterality documentation specifying right finger involvement
- ✓Exclusion of infectious processes through clinical evaluation
- ✓Assessment of finger function, range of motion, and grip strength
- ✓Treatment plan including conservative management or surgical options
- ✓Documentation of pain and functional impact on fine motor activities