Canada Research Chair in Musculoskeletal Rehabilitation, Trevor Birmingham, is working on a biomechanical approach that can slow the progression of knee osteoarthritis
Date published: 2026-05-11 12:00:00
3D gait analysis in the Wolf Orthopaedic Biomechanics Lab.
Photo: Western University
Deep, aching joint pain, stiffness and reduced range of motion are keeping the roughly four million Canadians who suffer from osteoarthritis (OA) from living their best lives. Since the knee is the most commonly affected joint for people with OA, many live with pain for several years (sometimes decades) while they wait for the optimal window to undergo knee replacement surgery—the definitive treatment for knee OA.
“Knee OA causes pain and decreases mobility—it limits the ability to remain active, stay healthy, work and play,” says Trevor Birmingham, Canada Research Chair in Musculoskeletal Rehabilitation. “The personal and economic costs of knee OA are huge.”
Birmingham, a physical therapist and biomechanist, is co-director of the Wolf Orthopaedic Biomechanics Lab (WOBL) at Western University’s Fowler Kennedy Sport Medicine Clinic, a state-of-the-art biomechanics lab. Aside from providing next-level gait analysis and imaging equipment, WOBL is a transdisciplinary space that brings health professionals together with scientists to work on innovative approaches to musculoskeletal disorders.
Recently, Birmingham and his team published their results from a clinical trial supported by funding from the Canadian Institutes of Health Research (CIHR). They discovered a lesser-known surgery—High Tibial Osteotomy (HTO)—not only reduced pain and other symptoms, it actually slowed the progression of joint damage significantly when performed on patients with moderate knee OA. The clinical trial was painstakingly designed with blinding mechanisms and external partners to ensure outcome measures would be valid and reliable.
“To our knowledge, this is the first study to show that a treatment for knee OA can modify the natural course of the disease, by both slowing down joint damage and improving symptoms at the two-year follow up,” says Birmingham.
A tale of two surgeries
Preparing a patient for 3D gait analysis in the Wolf Orthopaedic Biomechanics Lab.
Photo: London Health Sciences Centre Research Institute
He notes these results aren’t applicable to all patients with knee OA, since all 145 trial participants had two things in common—moderate OA (not end-stage) and varus alignment (bow-leggedness).
Varus alignment is a risk factor for knee OA. Although almost everyone puts more load on the inner portion of their knee when they walk, people with bowed legs do it even more, which can cause faster degeneration of the tissues. HTO surgery can lighten the load.
Jeffrey Gray, a personal support worker in southwest Ontario, had the HTO surgery in September 2025 after years of being prescribed steroids and pain medicines.
“Nothing worked,” says Gray. “For six years, whenever I was walking, I was in absolute agony. Then I was referred to the Fowler clinic and learned the pain was related to being severely bow-legged since birth.”
Gray says the surgery is one of the best things he’s ever done; 90% of the pain is gone.
“Unlike knee surgeries that remove or replace damaged joint structures, HTO attempts to preserve those structures by redirecting the loads acting on the joint,” says Birmingham. “It is very much a biomechanical intervention.”
Birmingham’s team did another study that showed 79% of patients who had the HTO surgery didn’t have to undergo additional knee replacement surgery afterwards.
Although the findings only apply to a portion of people with knee OA, these studies have wider implications, since they show correcting unfavourable biomechanics can lead to long-term benefits.
Standard of care
The HTO surgery might be the headliner, but Birmingham also highlights the importance of nonsurgical treatment for knee OA. All trial participants, whether they were in the surgery group or the control group, received the same standard of care—OA-specific exercise and education, delivered by therapists in the Fowler Kennedy Clinic.
“The group that had that standard of care plus the surgery had the largest improvements, but even the non-operative group had clinically important improvements in pain and function,” says Birmingham.
Trevor Birmingham.
Photo: Western University
“Our joints like to be moved, even when they have OA, so it's a good thing to stay active,” says Birmingham. “These interventions are intended to help people do that.”
Walk the walk
Birmingham, himself, had HTO surgery about 10 years ago. His varus alignment meant he had a higher risk for developing knee OA. However, it wasn’t his only risk factor.
“When I was younger, I had an anterior cruciate ligament (ACL) injury and reconstruction,” he says. “ACL is a common knee injury, particularly in young, active individuals. It’s also one of the strongest risk factors for the development of osteoarthritis.”
He says he knew 30 years ago that he had two important risk factors for knee OA. “So that only increased my interest in the topic as a physiotherapist and a biomechanist.”
Birmingham is well aware that not every HTO surgery will lead to outcomes as positive as the ones he’s enjoyed. The trial found that roughly 7% of participants had adverse events after the HTO—some even required follow-up surgery.
“I'm not part of the study I did,” says Birmingham. “But, I also had HTO and I'm doing well a decade later. You could say that not only do I talk the talk, I also walk the walk.”
Want to learn more?
To find out more about the research conducted at WOBL, visit the WOBL website. To learn about the HTO intervention, read an article about Birmingham’s study published by Western News or this paper, published in the Canadian Medical Association Journal, that evaluates the incidence of knee replacement after HTO.