Osteoarthritis, or OA, is initiated by damage to articular cartilage between the bones of joints and can lead to severe pain and debilitation. However, cartilage loss has not been found to predict the severity of symptoms, suggesting that other tissue may influence pain and disability.
With the assistance of an over $1.8 million grant from the National Institutes of Health, Dr. Kyle D. Allen, associate professor of the J. Crayton Pruitt Family Department of Biomedical Engineering, will investigate the conditions of several tissues as OA symptoms improve or deteriorate.
“What this grant is focused on is trying to look beyond the articular cartilage to see what changes in what tissues are really driving the symptomology of (OA),” Allen said.
The non-cartilage factors potentially contributing to OA symptoms that will be focused on in this project include bone structure, inflammation and neural sensitivity within rodent models of OA, Allen said.
Exercise, one of the most clinically effective forms of OA management, will allow tissue changes to be studied during improvement of OA symptoms.
Although effective, exercise can be difficult for some patients due to OA related pain. In addition, exactly how exercise elicits improvement in the first place is not yet completely understood, Allen said.
“With exercise, disability improved even though that exercise tends to not improve articular cartilage,” Allen said about a pilot study from his lab.
Symptoms, namely pain and disability, will be monitored by measuring changes in hind-limb sensitivity to touch and walking patterns, or gait.
Gait analysis will be performed using GAITOR Suite, an original system developed by Allen for OA models. This method utilizes highly sensitive force plates to fully detect ground forces exerted by walking in OA models, a unique feature as other systems only partially detect these forces, Allen said.
GAITOR Suite also includes high-speed video capture of up to 1000 frames per second.
“We can detect changes that are on the scale of hundredths of seconds (or) thousandths of seconds,” Allen said. “That has this huge effect because of the higher speed at which rodents walk.”
Findings from this study could bring about new drug targets to help alleviate symptoms and make it easier for patients to reap the benefits of exercise, Allen said.
“If there are things that we can do to protect the joint from pain during the act of exercising that might make exercising a little bit more feasible for the person to incorporate into their lifestyle then potentially, this is a better way of managing osteoarthritic pain and disability,” Allen said.
By Jonathan Griffin, BME Ph.D. student