M12.071
BillableChronic postrheumatic arthropathy [Jaccoud], right ankle and foot
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M12.071 an HCC code?
Yes. M12.071 maps to Reactive and Specified Arthropathies under the CMS-HCC V28 risk adjustment model (and Rheumatoid Arthritis and Inflammatory Connective Tissue Disease 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 M12.071
For M12.071to 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 M12.071 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M12.071 is the ICD-10-CM diagnosis code for chronic postrheumatic arthropathy [jaccoud], right ankle and foot. A chronic joint condition affecting the right ankle and foot that develops after rheumatic fever, characterized by reversible joint deformities without permanent damage to the joint structures. M12.071 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering inflammatory polyarthropathies (m05-m14).
Under the CMS-HCC V28 risk adjustment model, M12.071 maps to Reactive and Specified Arthropathies (HCC 94) with a community, non-dual, aged base RAF weight of 0.000. Under the older CMS-HCC V24 model, M12.071 maps to Rheumatoid Arthritis and Inflammatory Connective Tissue Disease (HCC 40) with a community, non-dual, aged base RAF weight of 0.307. 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.
This code encompasses both ankle and foot involvement on the right side; document which specific joints are affected. Because M12.071 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 M12.071 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code encompasses both ankle and foot involvement on the right side; document which specific joints are affected
- •Assess impact on ambulation and footwear tolerance as part of clinical documentation
Clinical Significance
Chronic postrheumatic arthropathy of the right ankle and foot represents a manifestation of Jaccoud's arthropathy that can significantly impact weight-bearing, ambulation, and balance following rheumatic fever. This condition requires specialized management to preserve lower extremity function while monitoring for cardiac complications.
Documentation Requirements
- ✓Established history of rheumatic fever
- ✓Specific right ankle and/or foot involvement
- ✓Evidence of chronic, reversible joint deformities
- ✓Clinical findings consistent with postrheumatic arthropathy
- ✓Imaging showing absence of joint erosions
- ✓Assessment of right ankle/foot function and gait
- ✓Current cardiac evaluation and status
- ✓Treatment plan and mobility assessment
Commonly Confused Codes
- •M12.072 — Left ankle and foot involvement instead of right
- •M12.079 — Unspecified ankle/foot when laterality is documented
- •M05.771 — Rheumatoid arthritis of right ankle/foot with erosions
- •M25.571 — Pain in right ankle and foot without arthropathy
- •M19.071 — Primary osteoarthritis of right ankle and foot