M89.641
BillableOsteopathy after poliomyelitis, right hand
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M89.641 an HCC code?
Yes. M89.641 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 M89.641
For M89.641 to 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 M89.641 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M89.641 is the ICD-10-CM diagnosis code for osteopathy after poliomyelitis, right hand. Bone disease that develops as a long-term consequence of polio infection, affecting the right hand. M89.641 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering other osteopathies (m86-m90).
Under the CMS-HCC V28 risk adjustment model, M89.641 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, M89.641 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 is used for post-polio sequelae affecting bone structure; ensure polio history is documented. Because M89.641 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 M89.641 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code is used for post-polio sequelae affecting bone structure; ensure polio history is documented
- •Verify laterality is clearly documented as right before assigning this code
Clinical Significance
Right hand post-polio osteopathy represents chronic bone changes in the hand bones following poliomyelitis infection, potentially affecting hand function, grip strength, and fine motor skills. This condition significantly impacts activities of daily living and requires specialized hand therapy.
Documentation Requirements
- ✓Documented history of previous poliomyelitis infection
- ✓Specific identification of right hand bone involvement
- ✓Imaging evidence of post-polio osteopathic changes in hand bones
- ✓Comprehensive right hand function assessment
- ✓Grip strength and pinch strength measurements
- ✓Fine motor skills and dexterity evaluation
- ✓Activities of daily living impact assessment
- ✓Hand therapy recommendations and adaptive equipment needs