Two Egyptian mummies were scanned in Los Angeles with half-millimeter precision, and doctors found something they weren't expecting in a 2,200-year-old spine

In January, a team at Keck Hospital of USC received a rare set of patients: two ancient Egyptian mummies, Nes-Min and Nes-Hor, on loan from the California Science Center before being put on display in “Mummies of the World: The Exhibition.” They took the lids off the wooden sarcophagi to do the scans, but doctors only had a few hours to do it before the mummies had to be put back into their cases for the show, which opens Feb. 7 and runs through Sept. 7.

Using the hospital’s most advanced CT scanner, Dr Summer Decker, Grace Whisler Professor of Medicine at the Keck School of Medicine and founding director of the USC Center for Innovation in Medical Visualization, was able to capture slices as thin as half a millimeter, about the width of a grain of sand. Each mummy had about 25,000 images compared to about 1,000 for a typical living patient. Decker, who studied forensic anthropology before going into medicine, said the team wanted to make sure they didn’t miss anything because once the mummies went on display they were going to be off-limits again.

As soon as the scans got underway, Decker could see the tiny details of how the bodies had been wrapped up centuries ago: the beaded net that had been draped over Nes-Min’s shroud, the spot where Nes-Hor’s blackened linen had been tucked in carefully to hold it in place. And those little things, she said, are reminders of the human hands that cared for these bodies once.

A hole in the spine that shouldn't be there
As Decker and her colleague Dr Jonathan Ford examined Nes-Min’s lower back, they identified a compression fracture in one of his vertebrae. That alone would have meant serious, chronic pain. But right behind the fracture they found something even stranger: a little hole in the bone with tool marks and signs that it had healed over time.

That combination suggests trepanation, a surgical technique in which ancient practitioners drilled or scraped a hole in bone to relieve pressure or pain. Trepanation of skulls has been documented before, but even then it appears to have been quite rare in ancient Egypt compared with other ancient cultures, according to a study published in Neurología. Nes-Min’s case is unique for its location. This appears to be one of the first documented cases of the procedure being performed on the spine rather than the head. Researchers are consulting with mummy specialists to confirm the discovery, and Decker said the team has been poring over the images for weeks.

They were real people with real pains and aches
The scans also revealed a left hip fracture in Nes-Hor, who died at around age 60, according to USC's research team. The injury never healed correctly, but the surrounding bone and muscle suggest he kept walking on that leg for years anyway.

Nes-Min, who lived around 330 BCE, was thought to have died from a dental abscess, but according to USC's research team, the new scans revealed his dental woes weren't serious enough to be life-threatening, leaving his true cause of death a mystery.

Diane Perlov, senior vice president for special projects at the California Science Center, was in the room when the scans were taken. She said getting right up to the mummies and seeing their well-preserved facial features made them feel startlingly familiar, almost like seeing someone you might pass on the street today. She said that finding out that these “exotic specimens” treated back pain, toothaches, and broken bones the same way we do today has a humanizing effect on visitors, turning ancient strangers into people we can relate to.

3D printing breathes life into 2,300-year-old objects
Alongside the medical results, Decker and Ford’s team 3D printed life-size copies of Nes-Min’s broken spine, Nes-Hor’s damaged hip and the protective amulets found on Nes-Min’s body, including ones in the shape of scarab beetles and a fish. The ancient Egyptians believed these amulets would help the dead reach the afterlife safely.

Decker, with the printed amulets in her hands, said it struck her that no human hand had touched anything like them in over two thousand years. The replicas are now part of the exhibition, offering a tangible link to the past for visitors. Experiences like these help people develop an emotional connection to history that pure information on a placard cannot, said Dr. Lynn Dodd, who runs USC’s Archaeology Research Center and its Extended Reality Lab. Her lab employs similar 3D tools to let people virtually interact with other historic objects, such as a 15th-century illuminated manuscript and artifacts from the oldest hunting lodge on Catalina Island.

A full-circle moment, and a reminder that science keeps moving
For Decker, this project was personal. As a graduate student, more than 15 years ago, she helped scan mummies and was part of the inaugural run of “Mummies of the World” in 2010. Nes-Min and Nes-Hor were last scanned in the 1990s; the improvements in image quality are part of the reason for the new findings.

You see that pattern elsewhere too. Imaging technology continues to improve, and with every upgrade, scientists can revisit objects and remains scanned decades ago with much less detail. The same logic applies to modern forensic work, where cold cases are reopened when DNA analysis is advanced enough to yield new information from old evidence.

Trepanation has a long, strange history across cultures, used for everything from treating head injuries to releasing evil spirits in some belief systems, according to a 2024 review in the Journal of Perioperative Practice. Another case study published in the journal Anatomy & Cell Biology found a probable case of therapeutic trepanation on a skull dating to the Old Kingdom period of Egypt, around 2181 to 2160 BCE. This indicates that the practice in Egypt may be even older than previously thought.

The larger point, Decker says, is that science keeps finding ways to speak to the dead. “There's something new coming out next year or the year after,” she said, “and it's going to change everything.”