When Egyptian scientists performed the first CT scan of the mummy of Tutankhamun, they turned up a key clue: Bone fragments from the pharaoh's...

CHICAGO — When Egyptian scientists performed the first CT scan of the mummy of Tutankhamun, they turned up a key clue: Bone fragments from the pharaoh’s first vertebra, near the skull, were not coated with embalming fluid.

Instead, the fragments were clean at the breaks, meaning that the damage had to have occurred after the pharaoh’s remains were prepared for burial. The evidence seems to rule out a blow to the base of the skull as the cause of Tut’s death, a theory in play ever since X-rays of the boy king were taken in 1968.

It’s most likely that the bones broke when Englishman Howard Carter and his team rough-handled the mummy after they discovered it in 1922, said Dr. Ashraf Selim, who reported the first detailed findings from the scans Monday at the Radiological Society of North America’s annual meeting in Chicago.

Selim, a radiologist at Kasr Eleini Teaching Hospital at Cairo University, led an international team of scientists who used a mobile CT scanner to obtain more than 1,900 digital cross-sectional images of the 3,300-year-old mummy.

Preliminary results of the scanning were announced early last year by Zahi Hawass, Egypt’s top archaeologist, who said the results indicated that Tut did not die from a blow to the head.

On Monday, Selim reported on how that conclusion was reached.

The sophisticated CT scans carried out by his team could pick out the residue of the resin used to preserve bodies in ancient Egypt, allowing the scientists to deduce when damage to the bones had occurred.

A second clue was found by examining a major fracture in Tut’s left thigh bone. The femur had a thin coating of embalming resin around the break, indicating that Tut had broken his leg just before he died and that his death may have resulted from an infection or other complications, Selim said. Another possibility is a fat embolism that could have acted like a clot to cause a heart attack.

“The leg fracture was induced just before death,” Selim said. “When they embalmed the body and poured liquid resin, it went through a wound to coat the edges of the fracture.”

Tut ascended to the throne at age 8 and was about 19 when he died.

Field Museum archaeologist James Phillips noted that although the images clearly show a leg fracture, the actual cause of death is still unknown.

“Yes, he broke his leg, and, yes, 1337 B.C. medicine wasn’t as great as it is today, and perhaps an infection occurred which caused death,” Phillips said.

“But there are other explanations. He might have died of natural causes — even a heart attack, stroke or other type of disease which was endemic in Egypt. It’s still up in the air.”