M01.X11
BillableDirect infection of right shoulder in infectious and parasitic diseases classified elsewhere
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M01.X11 an HCC code?
Yes. M01.X11 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 M01.X11
For M01.X11to 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 M01.X11 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M01.X11 is the ICD-10-CM diagnosis code for direct infection of right shoulder in infectious and parasitic diseases classified elsewhere. Direct infection of the right shoulder joint resulting from an infectious or parasitic disease classified elsewhere. M01.X11 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, M01.X11 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, M01.X11 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.
Always pair with a code from Chapter 1 (A00-B99) identifying the underlying infectious disease. Because M01.X11 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 M01.X11 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
Clinical Significance
Direct infection of the right shoulder in infectious diseases classified elsewhere represents a serious complication where a systemic infection has invaded the shoulder joint directly. This condition requires dual treatment targeting both the primary disease and the secondary joint infection.
Documentation Requirements
- ✓Documentation of primary infectious or parasitic disease
- ✓Evidence of direct right shoulder joint infection
- ✓Clinical signs of shoulder joint involvement
- ✓Treatment plan addressing both conditions
- ✓Code first the underlying infectious disease
- ✓Laboratory evidence of joint involvement
- ✓Differentiation from reactive versus direct infection
- ✓Assessment of shoulder function and mobility
Commonly Confused Codes
- •M00.811 — Arthritis due to other bacteria, right shoulder (primary bacterial)
- •M02.311 — Reiter's disease of right shoulder (reactive arthritis)
- •M01.X12 — Direct infection of left shoulder (wrong laterality)
- •M06.811 — Other rheumatoid arthritis of right shoulder (autoimmune)
- •M25.511 — Pain in right shoulder (symptom, not infection)