PhysOrg takes a deeper look at the reasons why prehistoric doctors poked holes in their patients’ heads:
However, evidence shows that healers in Peru practiced trepanation—a surgical procedure that involves removing a section of the cranial vault using a hand drill or a scraping tool—more than 1,000 years ago to treat a variety of ailments, from head injuries to heartsickness.
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“For about 400 years, from 600 to 1000 AD, the area where I work—the Andahuaylas—was living as a prosperous province within an enigmatic empire known as the Wari,” [Santa Barbara bioarchaeologist Danielle Kurin] said. “For reasons still unknown, the empire suddenly collapsed.” And the collapse of civilization, she noted, brings a lot of problems.
“But it is precisely during times of collapse that we see people’s resilience and moxie coming to the fore,” Kurin continued. “In the same way that new types of bullet wounds from the Civil War resulted in the development of better glass eyes, the same way IED’s are propelling research in prosthetics in the military today, so, too, did these people in Peru employ trepanation to cope with new challenges like violence, disease and depravation 1,000 years ago.”