YOU KNOW THE DRILL.

The article reports that in a long bone such as the femur, surgeons may use a device called an intramedullary nail, which consists of a hollow metal rod that is inserted into the canal of the bone marrow. Alfred Durham, an orthopedic surgeon practicing in Roanoke, Virginia, noted that it is hard to correct mistakes when drilling the hole through the bone. X-ray equipment must be aligned with the hole between the patient and surgeon, exposing his hand to direct X-rays while drilling. Durham had an idea of using a magnetic field and sensors to locate the predrilled hole in the metal tube, thus eliminating the need for X-rays. Durham stopped by the office of Alfred Wicks, a professor of mechanical engineering at Virginia Tech, and explained his idea.