Self-inflicted hammer blows to the head-Literature and case review

Self-inflicted hammer blows to the head are rare occurrences in forensic medicine, particularly when they are lethal. In the majority of cases, no distinction between self-inflicted injury versus assault has to be made. However, when assault is claimed and such distinction is required, the task may be challenging. We report a case concerning a 32-year-old psychotic woman, who had suffered multiple lacerations of the scalp and survived after claiming she had been assaulted with a hammer by an acquaintance. A clinical forensic examination was performed as well as the inspection of the scene of the incident for bloodstain pattern analysis. In summary, findings were inconsistent with assault and the injuries were determined to be self-inflicted. In addition, a retrospective analysis of our own autopsy records as well as a search in scientific literature and the internet for self-inflicted hammer blows to the head was conducted. For the majority of published cases a positive psychiatric history is reported. While published cases were few, potentially characteristic properties of self-inflicted hammer blows to the head were identified. For example, self-inflicted hammer blows may be identified by the absence of defensive wounds, injuries to the face and extracranial injuries and the finding that they are most commonly distributed in an area usually covered by a 'zuchetto' skull cap.