Tripartite Inca Bone in Skeletal Remains.
Shojiro Takasu
Abstract
Open AccessThe Inca bone, also known as the interparietal bone, is an anatomical variant resulting from incomplete fusion of the occipital bone during embryological development. Although its presence has been reported with varying frequencies among specific ethnic groups, its relevance in forensic anthropology remains underexplored. This report describes a human skull discovered along a riverbank, exhibiting advanced postmortem changes, including complete loss of soft tissue and dentition, as well as cranial bone destruction. Morphological analysis suggested the individual was a male over 40 years of age. Notably, a tripartite Inca bone was identified beneath the lambdoid suture. Due to its low prevalence and morphological variability, the Inca bone may serve as a useful marker in forensic identification and ancestry estimation. Accurate recognition of this variant is also important in cases of cranial trauma, where it must be differentiated from fractures. While the absence of antemortem data precluded positive identification in this case, radiological comparison with antemortem cranial imaging may facilitate identification in similar future cases. The identification of an Inca bone in forensic skeletal remains can provide meaningful anthropological and forensic insights. Forensic practitioners should remain aware of this anatomical variant during skeletal examinations to improve the accuracy of both trauma analysis and personal identification.