A child who lived on the Indonesian island of Borneo around 31,000 years ago underwent the oldest known surgical operation, an amputation of the lower left leg, researchers say.

One or more hunter-gatherers who performed the operation possessed detailed knowledge of human anatomy and considerable technical skill, enabling the youngster to avoid fatal blood loss and infection, say archaeologist Tim Maloney of Griffith University in Southport, Australia, and colleagues.

Healed bone where the lower leg was amputated indicates that the ancient youth survived for at least six to nine years after surgery before dying at age 19 or 20, the investigators report September 7 in Nature. Since there is no evidence of crushing from an accident or an animal’s bite at the amputation site, the researchers suspect that an unidentified medical problem led to the operation.

Maloney’s team excavated this individual’s remains in 2020 from a grave inside a large, three-chambered cave. Radiocarbon dating of burned bits of wood just below the grave along with another dating technique on a tooth from the youth’s lower jaw let the researchers estimate when the surgery took place.

Until now, the oldest known amputation involved a farmer from France whose left forearm was surgically removed nearly 7,000 years ago. In North Africa, surgeries to create skull openings may have occurred as early as 13,000 years ago (SN: 3/31/22).

Faced with rapid wound infections in a tropical region, ancient people on Borneo developed antiseptic treatments from local plants, Maloney’s group suspects. It’s unknown what type of tool was used in the Stone Age operation or whether the patient was sedated with a plant-based concoction.