A novel educational and personalized physical therapy program is showing signs that it may help people to mitigate their risk of developing knee osteoarthritis after an injury.
Speaking at the Canadian Arthritis Research Conference: Research with Impact, Jackie Whittaker, PhD, observed that initial work from the Stop Osteoarthritis (SOAR) program showed that meaningful improvements in knee-related quality of life and improvement in participants’ perceived self-management could be achieved.
Further feasibility work is ongoing and a proof-of-concept and phase 3 study need to follow, but the research suggests the approach could potentially help to reduce the substantial burden of managing people who develop posttraumatic OA (PTOA) of the knee.
Understanding the post–knee injury period
“Despite the progress that we’ve made in preventing injuries, and reducing disability in people with osteoarthritis, we lack good evidence about what should be done in the period between joint injury and the onset of osteoarthritis to delay or halt that onset,” Dr. Whittaker said at the virtual meeting, which was sponsored by the Arthritis Society, the Canadian Rheumatology Association, and Canada’s Institute of Musculoskeletal Health and Arthritis.
That’s where the SOAR program comes in. For the past 8 years, Dr. Whittaker, an assistant professor in the department of physical therapy at the University of British Columbia in Vancouver and affiliated to Arthritis Research Canada, and collaborators have been looking into the post–knee injury period with the aim of developing an intervention that could potentially reduce the risk of OA further down the line.
Much work has gone into understanding the burden and risk factors for PTOA of the knee in order to know who exactly to target with the intervention and what the risk factors may be for the subsequent development of OA .
This research suggests that knee injuries are most commonly seen in people aged between 15 and 35 years who participated in sporting or other physical activities, so this is the target population for the SOAR intervention.
Broadly speaking, sustaining any knee injury is associated with a sixfold increased risk for subsequent PTOA, Dr. Whittaker observed.
“Despite the fact that ACL [anterior cruciate ligament] and meniscal tears get all the press, collateral ligament injury are still associated with about a fivefold increased risk of osteoarthritis, and therefore maybe shouldn’t be so easily dismissed as an important target,” Dr. Whittaker said.
Postinjury risk factors for OA
“Basically, what all prevention comes down to is our understanding of risk factors and our ability to be able to modify them,” she said.
Previous joint injury is one of the strongest and most established modifiable risk factors for developing knee OA, and Dr. Whittaker and associates have performed two small but “mighty” cohort studies comparing people who have and have not had a knee injury. These two studies have looked at different time periods following injury to see if they could first identify the risk factors for developing OA some 3-10 years later, and then to look more closely at some of those risk factors in first 2 years after injury with a view to targeting these with an intervention.
Data analysis of the latter study is still ongoing but have shown that, among injured subjects, there is a fear of movement and reinjury, knee strength is weaker in both injured and uninjured knees, and they are perhaps less physically active than those who have not been injured.
“Going into those two studies, we knew that this group of people already [had an] increased risk for osteoarthritis because they had an injury. However, what we found is that it looks like this risk may be compounded through adiposity [and] deficits in muscle strength and physical inactivity, which are associated with pain, stiffness, lack of confidence, and at times, unrealistic expectations and poor pacing,” Dr. Whittaker said.
She added: “It also looks like some of these additional factors and particular adiposity or fat gain may develop after injury, which would then give us a concrete target for delaying or halting the onset of osteoarthritis in the segment of the population.”