M02.172
BillablePostdysenteric arthropathy, left ankle and foot
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M02.172 an HCC code?
Yes. M02.172 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 M02.172
For M02.172to 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 M02.172 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M02.172 is the ICD-10-CM diagnosis code for postdysenteric arthropathy, left ankle and foot. Joint inflammation in the left ankle and foot that develops after a dysentery infection (severe diarrheal illness). M02.172 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, M02.172 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, M02.172 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.
Ensure the dysentery infection has been documented and resolved before this post-infectious arthropathy develops. Because M02.172 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 M02.172 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Ensure the dysentery infection has been documented and resolved before this post-infectious arthropathy develops
- •Specify laterality (left) - do not use this code for bilateral or right-sided involvement
Clinical Significance
This diagnosis identifies postdysenteric arthropathy specifically affecting the left ankle and foot, representing a chronic reactive arthritis that severely impacts weight-bearing and ambulatory function. The condition requires comprehensive ongoing management due to its post-infectious inflammatory nature and essential role in mobility.
Documentation Requirements
- ✓Documented history of dysentery or severe diarrheal infection
- ✓Left ankle and foot involvement specifically identified
- ✓Clinical evidence of arthropathy affecting ankle/foot structures
- ✓Established timeline between infection and ankle/foot arthritis onset
- ✓Chronic or ongoing nature of joint symptoms
- ✓Weight-bearing and ambulation capacity assessment
- ✓Physical examination findings supporting ankle/foot arthritis diagnosis
Commonly Confused Codes
- •M02.171 — Postdysenteric arthropathy, right ankle and foot (opposite side)
- •M02.179 — Postdysenteric arthropathy, unspecified ankle and foot (when laterality unknown)
- •M00.072 — Staphylococcal arthritis, left ankle and foot (septic arthritis, not reactive)
- •M19.072 — Primary osteoarthritis, left ankle and foot (degenerative condition)
- •M25.572 — Pain in left ankle and joints of left foot (symptom code)