The Unbelievable Skills of Inca Surgeons

Would you undergo cranial trepanation surgery without anesthesia and without antibiotics? Don’t worry, there is no surgeon in the world who would propose it to you today, but in the past things were different, and not two or three hundred years ago: from the Incas to ancient Greece, it was a more widespread practice than previously believed – and in certain periods with excellent results.

At the time of those ancient civilizations, many were subjected to similar interventions and, as evidenced by the findings, many survived for months and years. Today, hundreds of cases of trepanations performed by Inca “doctors” are known with surprisingly high success rates, up to 80-90 percent – a much higher survival rate than similar operations performed, for example, during the American Civil War. , some 400 years later, which never exceeded 50 percent.

David Kushner (neurologist, University of Miami), John Verano (bioarchaeologist, Tulane University, New Orleans) and Anne Titelbaum (bioarchaeologist, University of Arizona) conducted research – published in World Neurosurgery (summary, in English) – on badger success of cranial surgery over different cultures and historical periods. Kushner explains: “It is possible that trepanations were initially designed to clean up skull fractures and relieve blood pressure on the brain after blows to the head,” however not all drilled skulls examined by the team show signs of injury, so it is possible that surgery has also been used to treat particular diseases, such as chronic headaches and mental illnesses.

Skulls with various types of trepanation have been found all over the world, but Peru, with its dry climate and excellent storage conditions, boasts hundreds of them. The team of researchers examined 59 skulls from the southern coast of Peru, dated between 400 and 200 BC. (I group), 421 artifacts from the central highlands of Peru, dated from 1000 to 1400 AD. (Group II), and 160 skulls from the highlands of Cusco, the capital of the Inca Empire, dated between the early 1400s. and the middle of 1500 A.D. (III group).

The clue to the success or failure of the surgery is given by the state of the bone around the trepanation: if there are no obvious signs of healing, the patient must have died during or shortly after the surgery. On the contrary, a smooth perimeter around the opening shows that the patient survived for months or years after the surgery.

The results of the study are surprising: only 40 percent of the first group survived the surgery, but then it goes to 53 percent for the second group and 83 percent during the Inca period (group III). There is also an astonishing 91 percent of surviving patients in another, actually small, sample of nine skulls from the northern highlands, dated between 1000 and 1300 AD.

According to the researchers, the techniques improve over time: smaller and less invasive holes, evidently to reduce the risk of damaging the protective membrane of the brain. «We were able to ‘see’ a progressive refinement in trepanation methods in a process that lasted a thousand years: those surgeons weren’t just lucky, they were really skilled! Several patients also seem to have survived multiple trepanations: a skull from the Inca era shows as many as five healed surgeries “, says the researcher

Kushner and Verano then compared the results achieved by Inca medicine with cranial interventions performed with similar methods on soldiers during the American Civil War. Surgeons from those battlefields also treated head injuries by cutting bones while trying not to puncture the delicate membrane of the brain. According to the medical records of the time, however, 46 to 56 percent of patients died, compared to 17-25 percent of Inca patients.

“These differences are partly justified by the nature of the injuries: on the battlefields of the Civil War the traumas must have been very different from those collected at the time of the Incas,” says Emanuela Binello, neurosurgeon (Boston University), who conducted similar studies on trepanation techniques in ancient China. Many Civil War soldiers suffered from gunshot and cannonball injuries and were treated in crowded and dramatically dirty hospitals, which certainly favored infections, “but the drill survival rate in Peru is still somewhat higher,” concludes Binello.