Question 1

What is ICD-10 code M89.49?

Accepted Answer

M89.49 is the ICD-10-CM diagnosis code for other hypertrophic osteoarthropathy, multiple sites. A condition where bones become abnormally thickened and enlarged in multiple areas of the body simultaneously, often causing clubbing of fingers and toes. M89.49 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).

M89.49 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This code indicates involvement of two or more anatomical sites; document all affected areas in the medical record.

Question 2

Is M89.49 an HCC code?

Accepted Answer

No. M89.49 is a billable ICD-10-CM code but does not map to any payment HCC category under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can still be reported on Medicare Advantage encounter data submissions, but it does not contribute to the beneficiary's Risk Adjustment Factor (RAF) score and therefore does not affect the risk-adjusted capitation payment to the plan. V28 reached 100% phase-in for payment year 2026.

Question 3

Is M89.49 billable?

Accepted Answer

Yes. M89.49 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. M89.49 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Question 4

Which HCC does M89.49 map to under V28?

Accepted Answer

M89.49 does not map to a CMS-HCC V28 payment category. Check the current CMS-HCC V28 model file for payment year 2026 rather than an older V24 tip sheet.

Question 5

What does M89.49 pay in RAF?

Accepted Answer

M89.49 has no separately stated V28 community RAF weight. If it is not a V28 payment HCC, it adds nothing to a community RAF score.

Question 6

What is the V28 vs V24 difference for M89.49?

Accepted Answer

M89.49 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither community model rewards M89.49 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's V28/V24 community RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a community payment HCC.

Question 7

What documentation supports M89.49?

Accepted Answer

This code indicates involvement of two or more anatomical sites; document all affected areas in the medical record Verify that multiple sites are truly involved before assigning this code rather than site-specific codes M89.49 is not a CMS-HCC payment code, so MEAT is not the payment hook. Documentation still has to support the diagnosis if you report it.

HCC Buddy Code Card

M89.49

Is M89.49 an HCC code?

Get the V28 RAF + MEAT cheat sheet

What This Code Means

Coding Tips

Child Codes

Code Hierarchy

Work M89.49 in HCC Buddy

M89.49 ICD-10-CM Code: Other hypertrophic osteoarthropathy, multiple sites

HCC Buddy Code Card

M89.49

Is M89.49 an HCC code?

Get the V28 RAF + MEAT cheat sheet

What This Code Means

Coding Tips

Child Codes

Code Hierarchy

Work M89.49 in HCC Buddy