Question 1

What is ICD-10 code M12.142?

Accepted Answer

M12.142 is the ICD-10-CM diagnosis code for kaschin-beck disease, left hand. Kaschin-Beck disease affecting the left hand, causing degenerative changes in the hand joints with pain and functional limitations. M12.142 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).

M12.142 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.

Confirm left hand is documented as the affected site.

Question 2

Is M12.142 an HCC code?

Accepted Answer

No. M12.142 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 M12.142 billable?

Accepted Answer

Yes. M12.142 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. M12.142 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

What is the V28 vs V24 difference for M12.142?

Accepted Answer

M12.142 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 model rewards M12.142 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

Question 5

What should coders know when reporting M12.142?

Accepted Answer

Confirm left hand is documented as the affected site If both hands are involved, assign both M12.141 and M12.142

M12.142

Is M12.142 an HCC code?

What This Code Means

Coding Tips

Code Hierarchy

Open M12.142 in the Interactive Encoder