New study indicates the success rates of skull surgeries by Incan premodern surgeons was shockingly high: up to 80% during the Inca era, compared with just 50% during the American Civil War some 400 years later.

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New study indicates the success rates of skull surgeries by Incan premodern surgeons was shockingly high: up to 80% during the Inca era, compared with just 50% during the American Civil War some 400 years later.