In the past few decades, scientists discovered prehistoric human skulls with traces of trepanation in several regions of the North Caucasus. They claimed that around 7,000 years ago, there were skilled surgeons in Ancient Greece, North and South America, Africa, Polynesia, and the Far East. They performed surgery on humans by drilling holes into their skulls. According to scientists, the most amazing thing is that ancient people survived the surgery and lived with holes in their skulls.
In 1997, archaeologists found several ancient skulls while excavating a prehistoric burial site near the Rostov-on-Don region, Russia. Elena Batieva, an anthropologist at the Southern Federal University in Rostov-on-Don was given the skulls to analyze and study them.
She immediately found the traces of trepanations in the skulls which belonged to the Bronze age, and they were unusual.
Later in 2016, Batieva teamed up with Julia Gresky, an anthropologist at the German Archaeological Institute in Berlin, and published their study in the American Journal of Physical Anthropology.
Scientists discovered 13 skulls (6 males, 6 females & one unidentified) with approximately equally spaced holes on the back of the heads.
Gresky found out that only two skulls showed no traces of healing, but the rest of them survived after the surgery. She suggested that there were skilled surgeons in ancient Russia.
Gresky and her colleagues found out that trepanation was performed in one of two ways: by scraping, in which the skull bone was scraped out with a sharp instrument until a hole formed in it, and by excision.
She also said that scraping is safer than excision, and the patient is more likely to survive after it. Her team examined 13 skulls, and out of them eight healed well, three not very well, and two did not heal at all.
She suggested that the scraping process helped ancient surgeons to know when to stop. They could scrape out with a clean, freshly chipped piece of flint, which helped to protect the wound from infection. It is possible that surgeons also used plants with anti-inflammatory properties.
She also explained that if the patient survived the first weeks and months after the operation, he/she did not develop inflammation, and the wounds healed. The hole in the skull was covered with skin, and scar tissue formed.
Scientists noticed that the largest hole was oval in shape, 9 centimeters long and about 4.5 centimeters wide.
It is still not clear why the ancient people drilled holes into the heads while performing surgery.
In some cases, surgery was performed due to trauma: an ancient surgeon tried to remove a piece of bone from a fractured skull to relieve pressure on the brain. This practice is known among the modern aborigines of the Kisii tribe in Kenya.
However, in a study by Gresky and her colleagues, the similar location of the holes and the absence of trauma that might require surgery led the researchers to speculate that the trepanation might not have been done for medical purposes.
Researchers believed that trepanation could have been done for ritual purposes.
A Russian archaeologist named Maria Mednikova who studied trepanation in other sites agreed that the skull drilling was done probably for performing rituals. They also analyzed the skulls, using X-rays and CT scans, but did not find any sign of tumors or injuries.