M86.341
BillableChronic multifocal osteomyelitis, right hand
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M86.341 an HCC code?
Yes. M86.341 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 M86.341
For M86.341 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 M86.341 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M86.341 is the ICD-10-CM diagnosis code for chronic multifocal osteomyelitis, right hand. A chronic bone infection affecting multiple areas of the bones in the right hand, including the metacarpals and phalanges. M86.341 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, M86.341 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, M86.341 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.
Confirm the infection involves multiple sites within the right hand rather than a single bone. Because M86.341 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 M86.341 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Confirm the infection involves multiple sites within the right hand rather than a single bone
- •Document which specific hand bones are affected for clinical clarity
Clinical Significance
Chronic multifocal osteomyelitis of the right hand represents a complex condition affecting multiple small bones, potentially causing significant functional disability and pain. This condition requires specialized treatment and monitoring due to the hand's complex anatomy and importance for daily activities.
Documentation Requirements
- ✓Specific documentation of right hand involvement
- ✓Evidence of chronic infection (duration >6 weeks or recurrent episodes)
- ✓Confirmation of multifocal involvement (multiple hand bones affected)
- ✓Imaging findings showing osteomyelitic changes in hand bones
- ✓Clinical assessment of hand function and pain levels
- ✓Laboratory results supporting infectious process
- ✓Documentation of treatment attempts and responses
- ✓Provider confirmation of chronic multifocal osteomyelitis diagnosis
Commonly Confused Codes
- •M86.141 — Acute osteomyelitis of right hand, differs by acute presentation
- •M86.342 — Same condition affecting left hand instead
- •M86.441 — Chronic osteomyelitis with draining sinus of right hand
- •M86.541 — Other chronic hematogenous osteomyelitis of right hand
- •M25.541 — Pain in joints of right hand, lacks infectious component