Inca bone, also known as the pre-Inca bone or os inca, is a relatively rare anatomical variation found in the human skull. It refers to an additional bone structure located in the posterior region of the cranium, specifically in the occipital area.
The Inca bone, seemingly named after the ancient Inca civilization, is considered an atavism, which is the reappearance of a trait or structure that was present in ancestral species but lost in subsequent generations. This anomaly is believed to be an evolutionary remnant from our distant ancestors, such as early hominids.
Typically, the Inca bone is a small, plate-like bone that is separate from the occipital bone and can be found either within the occipital bone or situated on top of it, creating an extra layer of bone. However, the size, shape, and position of the Inca bone can vary among individuals.
While having an Inca bone is mostly harmless and often goes unnoticed, it has been associated with certain conditions or disorders, such as cervical spine abnormalities or occipital neuralgia, where the occipital nerves become inflamed or compressed.
In summary, the Inca bone is an additional bone structure found in the posterior region of the skull, thought to be a throwback to our evolutionary ancestors. While it is usually benign, it can be linked to some medical conditions affecting the neck or head.
