What is this research about?
Osteoarthritis (OA) is the most common type of arthritis, affecting up to 5 million Canadians. People who have had a knee injury are much more likely to develop post-traumatic knee OA. To improve treatments and better predict disease progression, we need to understand how post-traumatic knee OA differs from non-traumatic knee OA that develops without injury. Do the joints or muscles work differently? In particular, the impact of how leg muscles work while walking was not well understood.
What did the researchers do?
Dr. Shawn Robbins and his team used motion capture cameras to study how people with post-traumatic and non-traumatic knee OA walked, compared to people without OA. They also used sensors to measure how seven different muscles in the thigh and calf were working.
What did they find?
Overall, the leg muscles in people with post-traumatic knee OA worked more similarly to people without any OA. In contrast, people with non-traumatic OA had more active thigh muscles and their knees moved differently. The results suggested that knee OA that occurs with or without a past injury have differences in their “biomechanics” – or the ways that the body moves.
How can this research be used?
This research adds significantly to the body of knowledge on OA biomechanics – the science of how the body moves with OA. Since people with non-traumatic OA moved in a different way than people without any OA, and since their knee muscles worked differently than those of people with post-traumatic OA, these muscle changes might be involved in initiating OA or its progression. On the other hand, in post-traumatic OA, it’s possible that OA starts more because of tissue damage resulting from the injury. These questions require additional research.
This study’s findings can be used by researchers to probe further into the fundamental differences between how OA works after an injury or without one, with implications for how each type should be managed.
What impact could this have?
Physical therapy and education are cornerstones of OA treatment, which can help people manage their symptoms and keep moving in their daily lives.
Understanding how the joints and muscles work in different types of OA could inform ways to retrain muscles to work differently or modify how people walk to prevent pain and minimize further damage. It could also help healthcare professionals to predict who might have a high risk of disease progression – people who might benefit from earlier treatment. This could help people with OA keep moving in their daily lives.
About the researcher
Dr. Shawn Robbins, who trained as a physiotherapist, is a scientist and associate professor at McGill University. His research was supported in part by an Arthritis Society Canada Young Investigator Operating Grant and Young Investigator Salary Award, both awarded in 2014.
Researcher Reflection
When working as a physiotherapist, I wondered why some people with knee osteoarthritis progress to severe stages of the disease. My work explores different factors in osteoarthritis progression and if these factors vary between different types of knee osteoarthritis. Finding these answers will help in the development of treatments that are patient-specific.
– Dr. Shawn Robbins, McGill University
Real-world Reaction
In the 35 years since my diagnosis of non-traumatic OA, my quest has been for information, research findings, knowledgeable healthcare professionals, and effective activity, exercise and movement routines. This recent OA biomechanics research helps me to continue to learn about the ‘keeping moving’ component that is so important in my life!
– Peter Pullinger, Arthritis Society Canada Online Consumer Panel Member