851.42 — Cerebellar or brain stem contusion without mention of open intracranial wound, with brief [less than one hour] loss of consciousness

851.42 is an ICD-9-CM diagnosis code for cerebellar or brain stem contusion without mention of open intracranial wound, with brief [less than one hour] loss of consciousness. ICD-9-CM was retired for U.S. claims on October 1, 2015, when ICD-10-CM took over.

The CMS General Equivalence Mappings translate it to 4 ICD-10-CM codes, such as S06.371A (Contusion, laceration, and hemorrhage of cerebellum with loss of consciousness of 30 minutes or less, initial encounter), S06.372A (Contusion, laceration, and hemorrhage of cerebellum with loss of consciousness of 31 minutes to 59 minutes, initial encounter) and S06.381A (Contusion, laceration, and hemorrhage of brainstem with loss of consciousness of 30 minutes or less, initial encounter). All of these are approximate matches, so review the record to pick the right one.