Finally, they added bacteria and showed that titanium beads with vancomycin on the surface killed the bacteria. When the beads were exposed to more bacteria, the vancomycin continued to kill the new infection. The vancomycin was not only chemically bound, but aggressively curtailed re-infection as well.
The researchers, led by Irving Shapiro, Ph.D., professor of orthopedic surgery at Jefferson Medical College, and including collaborators at the Rothman Institute at Jefferson and the University of Pennsylvania are supported by a grant from the U.S. Department of Defense to develop techniques to protect titanium surfaces with antibiotics.
"The recent results are another step toward our ultimate goal of preventing infections in battlefield fractures and hip and knee implants," Dr. Shapiro says.
"This technology bonding antibiotics to the implant surface is analogous to having land mines," says orthopedic surgeon Javad Parvizi, M.D., who treats implant-related infections and works on the project. "Once the organism steps on the surface, the antibiotic mine explodes and kills the bacteria. It holds great promise for our patients."
When a hip or knee implant is infected, physicians give extensive antibiotic treatment and the old implant is replaced. The treatment can include cement-containing antibiotics. "The hope is that the drugs in the glue will protect the implant, but that doesn't always work," Dr. Hickok explains. She notes that while they are infrequent, such infections can occur right after surgery from contamination during the operation. Later, infections can start on the implant from a different source in the body, such as a bladder infection or a dental procedure.
Dr. Wickstrom says the same approach can be used for other antibiotics and other implants. "There are plastic devices b
Contact: Steve Benowitz
Thomas Jefferson University