Research engineers at the Georgia Institute of Technology are refining a wearable device that can enable precise detection of noises emanating from the knee joint. In the future, this capability may assist orthopaedic specialists in assessing joint damage and tracking the progress of rehabilitation therapies. Omer Inan, PhD, assistant professor of electrical and computer engineering undertook the development work under a grant from the Defense Advanced Research Projects Agency (DARPA) who had issued a call for research proposals on wearable technologies for assisting rehabilitation of injured service personnel. Inan, a former NCAA champion discus thrower, had the further motivation of his own chronic knee pain from repeated joint stress during competition. His team of 17 researchers have published their work online in the journal IEEE Transactions in Biomedical Engineering.
The sounds of cracking and grinding, or crepitus, occur in healthy intact joints as well as those that have been compromised by injury or disease, but the resulting acoustic patterns are markedly different. An injured knee will produce erratic noise patterns, whereas a healthy knee produces a more constant sound. Using the new acoustic sensing technology, it may be possible to graph and decode the sounds of the knee in different motions and conditions, creating an intelligible physiological signal for clinicians to evaluate, similar to that of an electrocardiogram. Read more about this engineering advance and future potential here.