Grant: Doctoral: Vanier Canada Graduate Scholarships

Muscle activity determines how the load is applied to the knee joint, and this is crucial for knee osteoarthritis (OA) genesis and progression. The load application is controlled by two mechanisms: the first one is to change which portion of the muscle is active, thus altering in which direction each single muscle produces forces; secondly, the load can be changed by altering which muscles are activated in a coordinate way. Understanding if this happens in people with knee OA, and if this depends on the clinical presentation of the pathology, would likely change how knee OA is diagnosed and treated. To investigate these questions we will recruit 50 people diagnosed with knee OA and with different characteristics in terms of compartment of the joint that is most degenerated, self-reported pain and disability. As control group, we will recruit age- and sex-matched individuals. All participants will be required to perform a range of tasks, such as walking, standing up from a chair and squat for few seconds. Individual patterns of muscle activation will be extracted with two innovative techniques based on readings of their muscle electrical activity: the allows to study from single muscle from more than a hundred locations, while the second one enables to understand which muscles are activated simultaneously. These two techniques are optimal for understanding how muscle subportions and muscle coordination are altered in people with knee OA, as well as to relate this abnormal muscle activity to parameters such as localization of the degeneration, pain and disability. These findings will be a step forward towards a better understanding of what is dysfunctional in people with knee OA. This could be a starting point for scientists and clinicians to develop a new diagnostic tool, guide exercise prescription and verify the treatment effectiveness, contributing to prevent or slow the progression of knee OA in the long term.