Biosynthetic “fracture putty”
The most severe bone injuries are often repaired with a combination of bone grafts, pins, plates, screws, and even external fixators that hold pieces of bone in position during the healing process. These repairs often necessitate multiple surgeries and extended periods of recuperation. Even so, patients are often left with uneven results in terms of function. Sometimes, doctors treating these “non-union” fractures have no choice but to amputate the affected limb. Through a grant from the U.S. Department of Defense, orthopedic surgeon Dr. Bradley Weiner, Dr. Ennio Tasciotti, and a team from the Research Institute and other institutions are working to develop a different method for the repair of these severe orthopedic injuries — a point of particular interest for the Department of Defense, which is seeking more effective ways to avoid amputation and return soldiers to health after traumatic injury. In the project, Dr. Weiner and his colleagues have developed a form of “fracture putty” — called a BioNanoScaffold — designed to be injected into the site of the shattered bone. This putty includes nanoporous silicon embedded with bone growth factors; as it hardens, it will bear weight. In the meantime, the body’s own cells will gradually infiltrate the putty and begin creating new bone. As the putty slowly degrades, the regenerating bone will bear an
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1: BioNanoScaffold material (gray spheres) and growth factors (magenta) are injected into the fracture site. 2: As the material hardens, the body’s bone-creating cells infiltrate the area. 3: The BioNanoScaffold material naturally deteriorates, leaving behind healthy cells. 4: New bone forms, completing the healing process.
increasing share of the patient’s weight — aiding in functional recovery and strengthening the bone. Successful results may one day change the way severe injuries to bones are treated and may help to prevent countless amputations, for soldiers and civilians alike.
“ BioNanoScaffolds combine the mechanical advantages
of biodegradable synthetic polymers with the biological functions of natural biomaterial scaffolds. This approach achieves the correct strength requirements while enhancing the regeneration of healthy bone tissue at the fracture site.
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– Bradley K. Weiner, MD Vice Chair,
Department of Orthopedic Surgery
Medical Director, Surgical Advanced Technology Lab
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Houston Methodist Research Institute