An estimated 7.9 million bone fractures occur annually in the United States at an approximate cost of $70 billion. Of this number, about 10 to 20 percent do not heal. To address this problem researchers from the University of North Carolina at Chapel Hill School of Medicine have combined adult stem cells and a bone-generating hormone to correct bone fractures that do not heal.
 
Anna Spagnoli, MD, associate professor of pediatrics and biomedical engineering, and a team of researchers, have used an animal study to show that the transplantation of adult stem cells, which are combined with a bone-regenerating hormone, can heal bone fractures.

Bone fractures that do not heal within a normal period of time are referred to as non-union fractures. In the study, researchers used a mouse with a non-union fracture in order to transplant adult stem cells enriched with the bone-regenerating hormone IGF-1. 

Mesenchymal stem cells taken from the bone marrow of adult mice was engineered to express IGF-I, and put the stem cells into the others non-union fracture in the tibia. Then, using computed tomography (CT) scanning; Spagnoli found that mice treated with the stem cells enriched with IGF-1 healed better than those treated with stem cells alone or not treated at all. 

"We envision a clinical use of combined mesenchymal stem cells and IGF-1 similar to the approach employed in bone marrow transplant, in which stem cell therapy is combined with growth factors to restore blood cells," said Spagnoli. "I think this treatment will be feasible to start testing in patients in a few years."

This research was presented at The Endocrine Society's 93rd Annual Meeting in Boston, Massachusetts on Sunday, June 5.