January 27, 2022
Athletes and sports fans know that a torn ACL puts a player out of action, requires surgical repair, and involves a lengthy recovery. But for many injured athletes, being sidelined temporarily is just the start of a lifelong struggle.
According to Eni Halilaj, an assistant professor of mechanical engineering at Carnegie Mellon University and a biomechanic specializing in orthopedic rehabilitation, 60% of those who suffer from this common knee injury also develop osteoarthritis early in life. Degenerative joint disease, which affects approximately 32.5 million people in the United States, is particularly problematic for younger patients because of the longer duration the chronic disease can cause debilitating pain, stiffness, and stiffness. limited mobility.
“How can we make the 60% have the same long-term outcome as the 40%? asked Halilaj, who struggles to understand the difference between those who develop and those who do not develop osteoarthritis following knee trauma.
Halilaj and his interdisciplinary team of mechanical engineers, bioengineers and computer scientists strive to integrate insights from their experimental and computational work to develop effective rehabilitation strategies aimed at restoring and maintaining pain-free mobility. throughout life.
Halilaj’s motion capture lab experiments focus on identifying mechanical risk factors for debilitating diseases like osteoarthritis. The 1,000 square foot lab is equipped with 20 cameras positioned along the ceiling throughout the room, which are used to view highly reflective spherical markers strategically placed on a human subject’s body to track movement and analyze gait. . A split-belt treadmill further analyzes subject movement by measuring the force exerted by each step. Electromyography (EMG) sensors are used to assess muscle activations during movement by measuring electrical activity produced by skeletal muscles.
Although the data collected in this type of research laboratory is essential for identifying mechanical risk factors, patient access to these facilities is limited. Recent studies have shown that the presence of researchers observing gait analysis tests has a measurable effect on how patients walk, which could affect the reliability of the results of traditional gait analysis studies.
The key to better understanding may lie in monitoring how patients move in natural environments as opposed to specialized labs like Halilaj’s. Musculoskeletal Biomechanics Laboratory.
“Using flexible wearable sensors that look like band-aids, we monitor movement outside the lab, where patients don’t perform optimally and may adopt walking strategies to avoid pain that damages their joints at home. long term,” Halilaj said.
Her group combines wearable sensing data with advanced magnetic resonance imaging of the knee to uncover problematic gait strategies associated with early osteoarthritis – what she calls “digital biomarkers of osteoarthritis.”
In addition to gait adaptation after surgery, physiotherapy plays an important role in recovery. Recent advances in computer vision now offer untapped potential for motion analysis from video, enabling real-time tracking and feedback to improve physical therapy. Halilaj and his team are also developing open-source software that merges computer vision algorithms with biomechanical modeling to enable precise motion tracking from inexpensive cameras, like those built into personal smartphones.
Observational studies that monitor patients in physical therapy and natural settings will help researchers like Halilaj discover digital biomarkers of future disease, which can be targeted in the future with preventative technologies. Working with haptics experts, Halilaj’s team is developing wearable haptics systems to help train patients to change the way they move.
“In the not-too-distant future, we envision clinicians using data from these minimal wearable sensors and smartphone video to isolate the 60% of patients at risk of debilitating osteoarthritis, customize their treatment accordingly, and even prescribe a wearable haptic device that helps them correct their gait before it’s too late,” concluded Halilaj.