The use of pathological conditions in age and sex determination, important factors in personal identification, is not widespread in anthropology and legal medicine. Hyperostosis frontalis interna (HFI) is a bone condition that mainly affects the inner table of the frontal bone. Although there are numerous publications on the subject, at the present time its etiology remains obscure. Several associations of symptoms, whose incidence varies according to the population studied, have been described. Age and gender appear to be linked with the preponderance of this condition, as does the presence of behavioral disturbances. The aim of our study, based on a series of 1532 autopsies, was to define the incidence and the associations observed with other pathological conditions. Thirteen cases of HFI were identified (0.8% of autopsies), 12 women and one man whose mean age was 59.15 years (range: 42–79 years). All had behavioral disturbances and most were under psychiatric care. This study emphasizes the value of this condition in medico-legal identification.