M00.812
BillableArthritis due to other bacteria, left shoulder
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M00.812 an HCC code?
Yes. M00.812 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 M00.812
For M00.812to 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 M00.812 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M00.812 is the ICD-10-CM diagnosis code for arthritis due to other bacteria, left shoulder. A bacterial infection of the left shoulder joint caused by bacteria other than streptococcus, resulting in inflammation and pain. M00.812 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering infectious arthropathies (m00-m02).
Under the CMS-HCC V28 risk adjustment model, M00.812 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, M00.812 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.
Document the specific bacterial organism causing the infection for treatment planning. Because M00.812 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 M00.812 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Document the specific bacterial organism causing the infection for treatment planning
- •Confirm left shoulder involvement is clearly documented in the clinical record
Clinical Significance
Bacterial arthritis of the left shoulder represents a serious joint infection requiring urgent antibiotic therapy to prevent joint destruction and permanent disability. This condition significantly impacts patient mobility and quality of life, often requiring prolonged treatment and potentially surgical intervention.
Documentation Requirements
- ✓Specific identification of bacteria as 'other bacteria' (not streptococcus, staphylococcus, pneumococcus, etc.)
- ✓Confirmation of left shoulder joint involvement
- ✓Evidence of bacterial infection through culture, PCR, or other diagnostic methods
- ✓Documentation of arthritis symptoms (joint pain, swelling, limited range of motion)
- ✓Treatment with antibiotics or antimicrobial therapy
- ✓Exclusion of other causes of arthritis (autoimmune, crystal arthropathy)
- ✓Clinical signs of infection (fever, elevated WBC, increased ESR/CRP)
- ✓Joint aspiration results if performed
Commonly Confused Codes
- •M00011 — Staphylococcal arthritis of left shoulder (specific organism identified)
- •M00211 — Streptococcal arthritis of left shoulder (different bacterial type)
- •M06.812 — Other specified rheumatoid arthritis of left shoulder (autoimmune, not infectious)
- •M19.012 — Primary osteoarthritis of left shoulder (degenerative, not infectious)
- •M75.32 — Calcific tendinitis of left shoulder (calcium deposits, not infection)