M02.871
BillableOther reactive arthropathies, right ankle and foot
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M02.871 an HCC code?
Yes. M02.871 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 M02.871
For M02.871to 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 M02.871 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M02.871 is the ICD-10-CM diagnosis code for other reactive arthropathies, right ankle and foot. Joint inflammation in the right ankle and foot that develops as a reaction to an infection or other trigger elsewhere in the body. M02.871 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, M02.871 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, M02.871 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.
This code specifically indicates the right side; use M02.872 for left-sided involvement. Because M02.871 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 M02.871 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code specifically indicates the right side; use M02.872 for left-sided involvement
- •Document the underlying triggering condition (such as recent infection) to support medical necessity and provide complete clinical picture
Clinical Significance
This diagnosis represents reactive arthropathy affecting the right ankle and foot, indicating inflammation of these joints secondary to a remote infectious process. Ankle and foot involvement significantly impacts weight-bearing, ambulation, and balance, requiring comprehensive management to maintain mobility and prevent functional decline.
Documentation Requirements
- ✓Clinical evidence of right ankle and/or foot joint inflammation (swelling, pain, stiffness)
- ✓Documentation of reactive nature - inflammation secondary to remote infection
- ✓Specific anatomical location identified as right ankle and foot joints
- ✓Evidence ruling out direct septic arthritis or other infectious arthropathies
- ✓Documentation of triggering infection or infectious process (if identified)
- ✓Physical examination findings consistent with ankle/foot arthritis
- ✓Exclusion of other arthropathy types (rheumatoid, osteoarthritis, crystal arthropathy)
- ✓Assessment of functional impact on ambulation and weight-bearing
Commonly Confused Codes
- •M00.072 — Staphylococcal arthritis of right ankle and foot (infectious vs reactive)
- •M06.072 — Rheumatoid arthritis of right ankle and foot (autoimmune vs reactive)
- •M19.072 — Primary osteoarthritis of right ankle and foot (degenerative vs reactive)
- •M02.872 — Other reactive arthropathies, left ankle and foot (laterality difference)
- •M25.572 — Pain in right ankle and foot (symptom vs specific arthropathy diagnosis)