New medical tool that will reduce the exposure to X-rays for patients with broken bones

May 27 2004

Searching for a device to reduce X-ray exposure during surgery, Roanoke orthopedic surgeon Al Durham took his request to Carilion Biomedical Institute (CBI). The CBI Medical Director Andy Muelenaer collaborated with Alfred Wicks, associate professor in mechanical engineering in the College of Engineering at Virginia Tech.

Wicks involved his graduate students to develop a design. The result is a new, low-cost, hand-held magnetic surgical tool.

When surgeons set a long bone such as the femur, a titanium nail is inserted into the marrow cavity. To hold the bone in place, screws are drilled into small holes in the nail, which is the tricky part of the process.

With the new tool, a Magnetic Targeting Device, a doctor may precisely locate the holes for the screws. The process calls for sliding a magnet down the hollow tube of the large nail that will hold the broken femur together and uses electronic sensors instead of X-rays to find the exact location in the magnetic field of the screw holes.

One of Wick's students, David Szakelyhidi Jr., continued the design project as part of his graduate research and created a working device. CBI and the Virginia Tech Applied Biosciences Center (VTabc) funded his research. VTabc is a unique collaboration among Virginia Tech, the Carilion Health System, and the University of Virginia. Research activities range from basic biomedical research to experimental device development and laboratory demonstrations.

Szakelyhidi's design was passed on to Triad Semi-conductor of Winston-Salem, N.C. The company successfully developed a new surgical product with direction from Muelenaer.

Plastics One, a Roanoke based plastics engineering company developed the plastic handle to hold all of the electronic elements of the device.

In testing and surgery, the procedure using the device is precise. "The successful design of this product is a tribute to what students can do when given a real-world problem to solve," Wicks said.

The device will be used in orthopedic and trauma surgery and has multiple advantages. Battery-powered, the portable tool can be used in remote locations. Costing about $100, it can be disposed of after surgery. It reduces the amount of X-rays a surgeon is exposed to on a routine basis and also can eliminate the need for using costly and cumbersome X-ray equipment.

"Developing the Magnetic Targeting Device was truly a collaborative effort spearheaded by the CBI," Muelenaer said. "This project creates a powerful model to bring together physicians with the valuable research assets at Virginia Tech and those of local industrial partners such as Plastics One. I very much look forward to replicating this model on future projects."

A demonstration video using the Magnetic Targeting Device is available from CBI. For more information, go to: http://www.biomedicalinstitute.org.