Published in the International Journal of Paleopathology, the research conducted by Spanish scientists, primarily Sonia Díaz-Navarro from Valladolid University’s Prehistory Department, sheds light on this incredible find. The woman, aged between 35 and 45 at the time of death, was among 1,348 individuals resting in the graveyard used from 2,566 to 2,239 BCE. However, her skull bore evidence of a series of trepanations, surgical procedures involving the removal or scraping of the outermost layer, the dura mater, encompassing the brain and spinal cord.
The Surgical Evidence
Upon closer examination, two overlapping holes emerged between the woman’s forehead and the upper part of her ear. The larger aperture measured 53mm wide and 31mm long, while the second, smaller one measured 32mm by 12mm. The absence of fractures or distinct edges suggested these holes were not the result of injuries but rather remnants of two separate surgeries.
Díaz-Navarro remarks, “We identified two distinct holes resulting from two different interventions.”
The Surgical Technique
Analyzing the inclination of the holes and their walls, researchers determined that a “scraping technique” was employed in the trepanations. This process involved the gradual abrasion of the skull’s dome using a rough-surfaced stone tool, necessitating the individual’s likely immobilization or treatment with psychoactive substances to mitigate pain or induce unconsciousness.
Astonishing Recovery
Remarkably, the healed bone on the skull indicates the woman survived both surgeries. Researchers speculate she lived several months after the second operation.

Díaz-Navarro notes the rarity of documenting prehistoric surgical procedures, especially in the temporal region known as the “rarely seen event.” In the Iberian Peninsula, trepanation was more common in the frontal and parietal (upper) regions.
Challenges and Risks
Surgery in the temporal region posed inherent challenges due to natural difficulties in accessing it through the scalp. This area houses numerous blood vessels and muscles, making it vulnerable to easy bleeding during surgery.
However, prehistoric trepanations using the scraping technique proved more successful and secure than drilling. “Ancient surgeons often avoided harm to the meninges or brain, reducing the risk of postoperative infections. The use of sterile tools and plants with natural antibiotic properties might have contributed to preventing infections,” explains Díaz-Navarro.
Unfortunately, the reason behind the woman’s surgeries remains unclear. Despite evidence of healed rib fractures and some dental decay, these ailments likely had no connection.
“We cannot overlook the high prevalence of traumatic injuries documented in skeletons from Camino del Molino. The possibility of surgery being a result of trauma cannot be dismissed. The procedure could have eliminated signs of bruising or cuts, and damaged bone fragments might have been removed during the process.”