Humans have engaged in surgical practices for millennia, stretching far beyond modern hospitals and sterile techniques. Among the earliest forms of physical intervention, one procedure stands out as the most ancient and widely practiced: the surgical drilling or scraping of a hole into the human skull. This operation, known as Trepanation, is considered by archaeologists and medical historians to be the oldest known surgical procedure for which extensive evidence exists.
Defining the Ancient Operation
Trepanation is the intentional perforation of the cranium, creating an opening in the skull vault to expose the dura mater, the thick membrane covering the brain. The procedure was performed on living patients, distinguishing it from simple post-mortem examination or ritualistic bone removal. The physical evidence for this survival is found in the skeletal remains themselves, where the edges of the surgically created hole show signs of bone remodeling and healing.
This characteristic bone regrowth proves that the individuals lived for an extended period—weeks, months, or even years—following the operation. The medical context of this ancient procedure demonstrates that the practitioners were skilled enough to avoid immediately fatal damage to the brain and major blood vessels. The term itself is derived from the ancient Greek word trypanon, which translates to “borer” or “auger,” reflecting the nature of the technique.
Archaeological Timeline and Global Distribution
The history of trepanation extends deep into prehistory, with the earliest unequivocal evidence dating back to the Neolithic period, approximately 7,000 BCE. One of the oldest examples is a skull found in Ensisheim, France, dating back to this era. However, some evidence suggests the practice may have roots even earlier, possibly in the Mesolithic period around 6000 BCE in regions like North Africa and Ukraine.
This surgical practice was not confined to a single geographic area or culture, indicating a widespread, independent development across the globe. Over 1,500 trephined skulls from the Neolithic period alone have been uncovered across various continents, representing a significant portion of all cranial remains from that time. Notably, the procedure was common in ancient Peru, where it was practiced extensively by cultures like the Incas, and in parts of Europe, including France and Russia.
Archaeologists determine the age and success of these operations by meticulously analyzing the skeletal remains. The presence of smooth, rounded edges and osteoblastic activity—the formation of new bone—confirms that the patient survived the immediate procedure and the body initiated a healing response. In ancient Peru, for instance, a remarkable success rate of over 60% has been estimated based on the percentage of trephined skulls showing evidence of healing.
Purpose and Methods of the Procedure
The reasons for ancient people performing trepanation generally fall into two main categories: medical and magico-religious. On the medical side, the procedure was a common response to head trauma, such as depressed skull fractures resulting from combat or accidents. By removing bone fragments and relieving pressure, the operation functioned as a primitive form of emergency neurosurgery to treat subdural hematomas or swelling.
Ancient practitioners may have also employed the technique to treat chronic conditions like severe headaches, epilepsy, and seizures, which were often attributed to internal pressure or spiritual causes. The spiritual theory posits that the hole was created to release evil spirits or demons believed to be causing mental illness or pain in the patient. In some cultures, the removed bone fragment was even kept as a prized amulet to ward off further misfortune.
The methods used varied widely, but the fundamental techniques involved scraping, cutting, or drilling the bone using rudimentary tools. Stone implements, such as sharpened pieces of flint or obsidian, were the primary instruments used to create the opening. The scraping technique involved gradually abrading the bone until the inner layer was pierced, while the cutting method used intersecting incisions to remove a section of the cranium. Despite the high risk of infection and hemorrhage without modern antiseptics or anesthesia, the archaeological evidence demonstrates a surprisingly high survival rate in many prehistoric populations.