M86.142
BillableOther acute osteomyelitis, left hand
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M86.142 an HCC code?
Yes. M86.142 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 M86.142
For M86.142 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 M86.142 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M86.142 is the ICD-10-CM diagnosis code for other acute osteomyelitis, left hand. A sudden bone infection affecting the bones of the left hand, often resulting from puncture wounds, bites, or other traumatic injuries. M86.142 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, M86.142 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, M86.142 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.
Verify 'left' hand is specified in documentation. Because M86.142 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 M86.142 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify 'left' hand is specified in documentation
- •Hand osteomyelitis can progress rapidly; ensure acute status is confirmed and appropriate treatment is documented
Clinical Significance
Acute osteomyelitis of the left hand bones poses significant functional threats due to the complex anatomy and fine motor requirements of hand function. This condition often results from puncture wounds or trauma and requires immediate intervention to preserve hand mobility and prevent disability.
Documentation Requirements
- ✓Specific identification of left hand bone involvement
- ✓Documentation of acute onset infection
- ✓Clinical evidence of hand bone infection (swelling, pain, fever)
- ✓Imaging confirmation of osteomyelitis in hand bones
- ✓Laboratory support for active infection
- ✓Documentation of causative factors (trauma, puncture wound)
- ✓Assessment of functional impact on hand use
- ✓Treatment plan including surgical consideration if needed