Surgeons have used stem cells from fat to help repair skull damage in a seven-year-old girl in Germany.
It was apparently the first time such fat-derived cells have been exploited to grow bone in a human.
The girl had been injured two years before in a fall, which destroyed several areas of her skull totaling nearly 19 square inches, the German researchers reported.
Other surgeons had failed to correct the defects, and the girl wore a protective helmet. Her brain could sometimes be seen pulsating through the missing areas of her skull.
But several weeks after the stem-cell surgery, she was able to leave her helmet behind, the researchers report in the December issue of the Journal of Cranio-Maxillofacial Surgery.
The skull is now smooth to the touch, the missing parts replaced by thin but solid bone, said Dr Hans-Peter Howaldt of the Justus-Liebig-University Medical School in Giessen, Germany.
Dr Howaldt, who performed the surgery last year, said the damage was too extensive to be repaired with bone grafts from her body. He said the hope was that if bits of the child's bone were mixed with stem cells, the cells would turn into bone-building cells that would create additional bone.
That appears to have happened. "I cannot prove that our success comes from the stem cells alone," Dr Howaldt said, "but the combination of the two things simply worked".
Dr Howaldt and his colleagues recovered bone from the girl's pelvis and about 1.5 ounces of fat tissue from her buttocks.
The bone was milled into chips about one-tenth of an inch long and placed in the missing areas of the skull. Then surgeons added the stem cells to the bone chips. The cells had been extracted from the girl's fat in a laboratory while surgeons prepared the girl's skull.
Dr Howaldt said the bone chips appeared to instruct the stem cells to make more bone. While the new bone should grow as the child grows, she's old enough that her skull won't grow much more anyway, he said.
AP