Experts from a US museum believe it could be one of the oldest examples of advanced surgery. The Museum of Osteology in Oklahoma said the skull is reported to have been that of a man who was injured in battle before undergoing surgery to implant a piece of metal in his head to repair a fracture.
https://www.nationalgeographic.com/history/article/what-is-trepanation-skull-surgery-peru-inca-archaeology-science