L98.A298 ICD-10-CM Code: Non-pressure chronic ulcer of unspecified forearm with other specified severity

L98.A298 is the ICD-10-CM diagnosis code for non-pressure chronic ulcer of unspecified forearm with other specified severity. A long-lasting open sore on the forearm (side not specified) that is not caused by pressure, with a specific but unusual severity level documented. L98.A298 sits in the ICD-10-CM chapter for diseases of the skin and subcutaneous tissue (l00-l99), within the section covering other disorders of the skin and subcutaneous tissue (l80-l99).

Under the CMS-HCC V28 risk adjustment model, L98.A298 maps to Diabetic Skin Ulcer and Severe Skin Conditions (HCC 383) with a community, non-dual, aged base RAF weight of 0.517. L98.A298 was not retained as a payment HCC under the older V24 model, so V28 introduced or recategorized it during the 2024–2026 phase-in. 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.

Use this code only when the severity does not fit into the standard categories (1-6) but is specifically documented. Because L98.A298 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.