Tut had been affixed to his coffin by resins used in the embalming process.
Carter and his colleagues dismembered much of the mummy while removing the body from its sarcophagus. The damage they did is in some cases difficult to distinguish from the damage dating back to the king's lifetime or the embalming process.
During an x-ray of the mummy in 1968, scientists found bone fragments in Tut's skull, prompting a sensational theory that the boy king had been bludgeoned to death by his political enemies during a particularly volatile time in Egyptian history.
(See a National Geographic magazine feature on King Tut's life and death.)
The latest scan, however, showed no skull fractures. It did show that the two bone fragments in Tut's cranial cavity exactly matched some missing pieces from the pharaoh's first vertebra, near the skull.
Because the fragments were loose and not covered with solidified embalming material, the damage must have occurred after the pharaoh's remains were prepared for burial, scientists concluded.
Selim believes the bone fragments may have been dislodged when Carter's team tried to remove Tut's gold mask, which was tightly glued to the body.
"The damage probably occurred because of the bad handling of the mummy," Selim said.
"If these pieces of bone [were dislodged] before death, we would assume they would be stuck to the resin inside the skull, not just loose there."
The scientists set up a mobile, noninvasive CT scanner in Luxor to perform a full-body scan on the king's remains, obtaining about 1,900 digital cross-sectional images.
Selim says Tut's remains are "in a terrible shape," with most of the bones having been broken after the mummy was discovered.
The scientists have focused on a fracture in Tut's left thigh bone as the most likely cause of death.
The CT scan showed a thin coating of embalming resin around the leg break, suggesting that Tut broke his leg just before he died and that his death may have resulted from an infection or other complications.
"The resin flowed through the wound and got into direct contact with the fracture and became solidified, something we didn't see in any other area," said Selim.
"We could not find any signs of healing of the bone."
There were no antibiotics 3,000 years ago, so the probability of a severe infection resulting from such a break would be quite high, according to Selim.
"It's probably what killed him," he said.
John Benson, who is the chief of radiology at Mount Desert Island Hospital in Bar Harbor, Maine, has used similar medical imaging to determine what killed a group of French settlers who arrived on Saint Croix Island in Maine in 1604.
He agrees that the leg break likely led to Tut's death.
"But there's always going to be speculation," he said.
"There is a number of possible causes of death for which there would be no residual evidence. Tut could have had pneumonia, or he could have died from a communicable disease.
"Maybe his immune system was a little impaired because he was trying to heal the [leg] fracture, and he caught some other kind of disease that we wouldn't really be able to prove one way or the other."
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