Some see horses and cows in a field. We see a way to stop us going weak at the knees.

“The knees of horses and cows are allowing us to better understand human knee weakness and offer us a new, powerful means to understand osteoarthritis.”

Professor Richie Gill, Department of Mechanical Engineering

Professor Richie Gill expects that almost a quarter of us will experience osteoarthritis in our knees at some point. Perhaps no surprise when osteoarthritis is fast becoming the leading cause of disability around the world.

Each year, 90,000 of us are already having knee replacements. And, as our population ages and obesity increases, this figure is expected to rise by 120% in the next decade. Because replacements don’t last forever, re-do, or ‘revision’, operations are sometimes needed, especially for younger patients who are at greater risk of requiring one.  In the next 10 years, the number of revisions is expected to rise by a staggering 300%.

Osteoarthritis is the degeneration of joint cartilage and underlying bone. It causes pain and stiffness, usually getting worse over time. It particularly affects our hips, thumbs and knees – which is where Professor Richie Gill, in our Centre for Orthopaedic Biomechanics comes in.

Richie is finding ways to discover more about knee joint cartilage and so better understand osteoarthritis. With the development of a new analysis tool to measure and test collagen he has chosen horses and cows for comparison as there are correlations between the lifestyle of an animal and the form and function of its knees. Horse knees are those of ‘well evolved joggers,’ and cows are more those of ‘domesticated couch potatoes.’

Professor Richie Gill said ‘Our method enabled us to study the makeup of cartilage in the knees of cows and horses, rather than just knee morphology – how the knee joint is formed. Overall we saw highly significant differences between the cartilage of horses and cows. Horse cartilage is thicker, compresses less and has a greater resistance to deformation – it almost certainly developed this way to allow for the speeds at which horses travel, and increased pressure on the knee joint.

“Our observations have implications for the study of human knee cartilage and its diseases. Evolutionary pressures in human knees may have increased our knee range of motion, but not driven significant change in cartilage material properties.”

Looking further, our research could offer a new, powerful means to understand osteoarthritis and classify knee joint failures – literally helping us to stop going weak at the knees.

Related links

Find out more about Richie Gill

Listen to Richie Gill’s inaugural lecture ‘What is wrong with knee replacement?’

Centre for Orthopaedic Biomechanics

Centre for Regenerative Medicine