M65.931
BillableUnspecified synovitis and tenosynovitis, right forearm
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M65.931 an HCC code?
No. M65.931 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).
What This Code Means
M65.931 is the ICD-10-CM diagnosis code for unspecified synovitis and tenosynovitis, right forearm. Inflammation of the tissue lining tendons and joints in the right forearm. This causes pain, swelling, and reduced grip strength or forearm movement. M65.931 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering disorders of synovium and tendon (m65-m67).
M65.931 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.
Ensure documentation clearly indicates 'right' forearm to avoid laterality errors.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for M65.931 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Ensure documentation clearly indicates 'right' forearm to avoid laterality errors
- •Consider if this is related to repetitive strain injuries or occupational activities