Broken bones in humans and animals are painful and often take months to heal. Studies conducted in part by University of Georgia Regenerative Bioscience Center researchers show promise to significantly shorten the healing time and revolutionize the course of fracture treatment. Fractures in rats have been healed in two weeks. They are trying to get consistent results with sheep. Even before this works on humans there would be a market for repairing the bones of thoroughbred horses.
Researchers used plasmalemmal sealing and axonal repair by polyethylene glycol and methylene blue and microsutures to repair rat sciatic nerves in minutes and days instead of months and years.
To start the bone regeneration process, the RBC used adult stem cells that produce a protein involved in bone healing and generation. They then incorporated them into a gel, combining the healing properties into something Stice calls “fracture putty.”
With Peroni’s assistance, the Houston-based team used a stabilizing device and inserted putty into fractures in rats. Video of the healed animals at two weeks shows the rats running around and standing on their hind legs with no evidence of injury. The RBC researchers are testing the material in pigs and sheep, too.
“The small-animal work has progressed, and we are making good progress in large animals,” he said.
More work is needed to get to human medical trials, but the threat of losing federal funding for biomedical work through the DOD means they will have to find new ways to fund the project.
“Complex fractures are a major cause of amputation of limbs for U.S. military men and women,” said Steve Stice, a Georgia Research Alliance Eminent Scholar, animal and dairy scientist in the UGA College of Agricultural and Environmental Sciences and director of the UGA Regenerative Bioscience Center.
“For many young soldiers, their mental health becomes a real issue when they are confined to a bed for three to six months after an injury,” he said. “This discovery may allow them to be up and moving as fast as days afterward.”
Stice is working with Dr. John Peroni to develop a fast bone healing process. “This process addresses both human and veterinary orthopedic needs,” said Peroni, an associate professor of large animal surgery in the UGA College of Veterinary Medicine and a member of the RBC.
“The next step is to show that we can rapidly and consistently heal fractures in a large animal,” Peroni said, “then to convert it to clinical cases in the UGA [College of Veterinary Medicine] clinics where clinicians treat animals with complex fractures all the time.”
Once they have something that works for animals, it will be passed over to the DOD for human use.
Peroni, who is chairman of the North American Veterinary Regenerative Medicine Association, is hopeful this material will be promoted to the veterinary and human medical fields through the educational efforts of NAVRMA and the RBC.
However, the RBC isn’t the only group working on a faster fix for broken bones.
“Our approach is biological with the putty,” Stice said. “Other groups are looking at polymers and engineering approaches like implants and replacements which may eventually be combined with our approach. We are looking at other applications, too, using this gel, or putty, to improve spinal fusion outcomes.”