It was thought that fibrin played a key role in fracture healing. However, a new study from Vanderbilt University suggests that may not be the case.
Instead, the research team suggests in a news release from Vanderbilt University Medical Center, it is the breakdown of fibrin that is essential for repairing bone fractures.
The study was recently published in the August issue of Journal of Clinical Investigation.
“Many of the current pharmaceutical protocols are based on using fibrin to promote fracture healing,” says Jonathan Schoenecker, MD, PhD, assistant professor of Orthopaedic Surgery and Rehabilitation and one of the study’s authors, in the release.
“In certain instances it may help, but we’ve shown for sure that you don’t need it. Bone biology does not require fibrin to heal a fracture,” he continues in the release.
Fibrin is involved in blood clotting; it forms a meshlike net that traps platelets to form a clot. When bones break, so do blood vessels, and clots form to stop the bleeding, the release explains.
Since fibrin is the main protein at the site of a fracture, it was thought to promote repair by providing a scaffold for the initial phase of new bone formation. Schoenecker and colleagues found, however, that fracture repair was normal in mice missing the fibrin precursor fibrinogen, the release continues.
The findings may explain why obesity, diabetes, smoking, and advanced age impair fracture repair. They are all associated with impaired fibrin clearance, Schoenecker explains in the release.
Per the release, the findings may also explain why children heal so quickly—because their fibrinogen levels are about half the levels in an adult.
“If we could lower fibrinogen levels—or increase the activity of enzymes that get rid of fibrin—we could make adult patients more like kids and improve healing,” Schoenecker states in the release.
Schoenecker and his team are working toward “orthobiologics” to reduce fibrin levels or enhance fibrin clearance and improve fracture healing. They are also working to improve the mechanical devices—such as rods and plates—used in orthopaedic surgeries, so that those devices don’t disrupt the ability of blood vessels to grow and reconnect, the release explains.
He points out in the release that some of the medications developed for cardiovascular medicine—to prevent clotting—may find new purposes in enhancing tissue repair and regeneration.
[Source(s): Vanderbilt University Medical Center, Science Daily]