M86.119
BillableOther acute osteomyelitis, unspecified shoulder
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M86.119 an HCC code?
Yes. M86.119 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 M86.119
For M86.119 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 M86.119 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M86.119 is the ICD-10-CM diagnosis code for other acute osteomyelitis, unspecified shoulder. A sudden bacterial bone infection in the shoulder that is not blood-borne in origin, when the specific side (left or right) is not documented. M86.119 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, M86.119 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, M86.119 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.
Use this code only when laterality cannot be determined from documentation. Because M86.119 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 M86.119 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code only when laterality cannot be determined from documentation
- •Query provider if shoulder laterality is clinically relevant but not documented
Clinical Significance
Other acute osteomyelitis of unspecified shoulder represents non-hematogenous bone infection where laterality cannot be determined from available documentation. This condition requires immediate antibiotic intervention and close monitoring to prevent progression to chronic infection, joint destruction, and permanent shoulder dysfunction.
Documentation Requirements
- ✓Documentation of acute osteomyelitis involving shoulder
- ✓Confirmation that infection is not hematogenous in origin
- ✓Evidence that shoulder laterality is unspecified or unknown
- ✓Clinical presentation consistent with shoulder bone infection
- ✓Imaging findings supporting osteomyelitis diagnosis
- ✓Laboratory markers indicating active infection
- ✓Culture results and organism identification when possible
- ✓Assessment of shoulder function and mobility restrictions