M02.18
BillablePostdysenteric arthropathy, vertebrae
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M02.18 an HCC code?
Yes. M02.18 maps to Bone/Joint/Muscle/Severe Soft Tissue 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 M02.18
For M02.18to 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 M02.18 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M02.18 is the ICD-10-CM diagnosis code for postdysenteric arthropathy, vertebrae. Joint inflammation of the spine and vertebrae that develops as a complication after dysentery infection. M02.18 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, M02.18 maps to Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis (HCC 92) with a community, non-dual, aged base RAF weight of 0.479. Under the older CMS-HCC V24 model, M02.18 maps to Bone/Joint/Muscle Infections/Necrosis (HCC 39) with a community, non-dual, aged base RAF weight of 0.401. 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 vertebral region affected if possible (cervical, thoracic, lumbar) for more precise coding. Because M02.18 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 M02.18 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Document the specific vertebral region affected if possible (cervical, thoracic, lumbar) for more precise coding
- •Confirm this is post-dysenteric and not another form of spondyloarthropathy
Clinical Significance
Postdysenteric arthropathy of the vertebrae represents a serious form of reactive arthritis affecting the spine following dysentery infection. This condition can cause significant spinal inflammation, pain, and functional limitation, requiring specialized management due to its potential impact on spinal stability and neurological function.
Documentation Requirements
- ✓History of dysentery or severe infectious diarrheal illness
- ✓Vertebral or spinal involvement documented
- ✓Evidence of spinal arthropathy (pain, stiffness, decreased mobility)
- ✓Temporal relationship between infection and spinal symptoms
- ✓Chronic or persistent nature of spinal inflammation
- ✓Functional assessment of spinal mobility and activities
- ✓Imaging or physical findings consistent with vertebral arthropathy
Commonly Confused Codes
- •M02.19 — Postdysenteric arthropathy, multiple sites (when multiple joints affected)
- •M46.1 — Sacroiliitis, not elsewhere classified (specific sacroiliac involvement)
- •M45.9 — Ankylosing spondylitis, unspecified (different spondyloarthropathy type)
- •M48.1 — Ankylosing hyperostosis [Forestier] (degenerative spinal condition)
- •M54.9 — Dorsalgia, unspecified (symptom of back pain, not diagnostic)