S72.8X9C ICD-10-CM Code: Other fracture of unspecified femur, initial encounter for open fracture type IIIA, IIIB, or IIIC

S72.8X9C is the ICD-10-CM diagnosis code for other fracture of unspecified femur, initial encounter for open fracture type iiia, iiib, or iiic. S72.8X9C sits in the ICD-10-CM chapter for injury, poisoning and certain other consequences of external causes (s00-t88), within the section covering injuries to the hip and thigh (s70-s79).

Under the CMS-HCC V28 risk adjustment model, S72.8X9C maps to Pathological Fractures (HCC 402) with a community, non-dual, aged base RAF weight of 0.000. Under the older CMS-HCC V24 model, S72.8X9C maps to Hip Fracture/Dislocation (HCC 170) with a community, non-dual, aged base RAF weight of 0.451. 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.

Coders should report S72.8X9C only when the provider documentation supports the specific condition described, since more specific codes within the same hierarchy can capture additional clinical detail and may carry a higher RAF weight. Because S72.8X9C 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.