Rehab sensor sticks directly to the bone

Researchers at the University of Arizona http://arizona.edu have developed a new sensor for monitoring bone recovery. The sensor is attached directly to the bone and provides doctors with important data on the healing process of fractures. The data from the paper-thick electronics is read out using NFC. An electromagnetic field from the outside activates a tiny coil in the electronics, which generates enough electricity for a transmitter, which is also integrated, to transmit the data to the outside.

For rehabilitation and therapy

The sensor is barely bigger than a one pence coin. "This technology platform allows us to develop investigative tools to figure out how the musculoskeletal system works and use the information we collect for rehabilitation and therapy," says Philipp Gutruf, assistant professor of biomedical engineering. "Because the device is so thin, it easily conforms to the curvature of the bones," adds graduate student Alex Burton.

Fractures associated with conditions like osteoporosis make for longer hospital stays than heart attacks or breast cancer. That could change with the small device, the researchers hope. Once approved for use in humans, they say, it could be used not only to monitor healing but also to improve health. For example, it will indicate when the stability of the bone decreases to such an extent that new fractures are imminent.

Adhesive fuses with bone

The novel sensor is attached to the bone with a special adhesive, which is considered to be the body's own. Normal adhesives would be rejected after a short time, as the outer layer of bone regularly renews itself. The adhesive and thus the sensor would fall victim to this process. John Szivek, Professor of Orthopaedic Surgery and Biomedical Engineering, solved the problem. His adhesive, which contains calcium particles with an atomic structure, resembles that of bone cells. "The bone thinks the device is part of it and grows together with it," Gutruf says. "This creates a permanent bond, so measurements can be made over long periods of time."

Source: pressetext, Wolfgang Kempkens