I can say it, I have runner’s knee. It popped in yoga class April before last but I think it stems from getting hit by a car and fracturing my hip when I was 16. More about that later. So I called my friend with a PhD in physiotherapy and she sent me exercises and told me not to get a brace. So I got a little brace then a bigger one. I also read for like 100 hours about runners knee and braces on running blogs. Now I’m back to the little one and wondering what is the science on runners knee I mean I am a scientist after all so here it is. As a scientist I know I’m no expert on this but I know where to find the good stuff. It’s all peer-reviewed and referenced, your welcome.
My sore knee
I’ve talked a bit about this in other posts but here is the whole storey. When I was 16 I was backed into very, very slowly in a crosswalk. For not really all that great reasons I didn’t get to go to the hospital right away and it hurt like hell. About 2 months later I got X-rays and they showed a mostly healed hairline fracture in the stem that connects the ball of the hip to the pelvis and later as it acted up more X-rays and they called it traumatic bursitis. Every so often it acted up, but reliably so when I did a rescue with egg-beater kick as a lifeguard. Some days it put me on the couch. But in my late 20’s it was almost never a major issue save for one random couch day at 29.
Then about four or five years ago I made exercise more of a priority mostly mountain biking and some running. It was never an issue. Two years ago I got into road racing and started doing a training plan for my first 10k at Bluenose. That meant running became my main thing and I was out there 5 days a week. I was fit from 1000’s of km on my bike in the woods, shovelling the winter’s record breaking snowfalls (200 m driveway), lots of yoga and splitting 4 chord of wood very inefficiently (video evidence of how I started) with a 10 lb maul. But that spring I dove into running foot first going from nothing to 35+ km a week. Classic overtraining. One day for the first time in a long time my hip hurt again so I called my friend from MtA with a PhD in physiotherapy. She gave me some exercises and they worked, I stopped doing them and went back to running full steam ahead. Then one day at yoga my knee popped and I’ve had issues with it ever since. That 10k hurt like hell and I have the pictures to prove it. So I called Gill again and she told me to sit the f&^$ on the couch until it stopped hurting, gave me some exercises, in the form of a screen shot and told me not to buy a brace and if I did make it a strap only, since bigger ones just keep you injured. So I kept running, and now half marathon training, with my little strap brace. This training program followed the rules like the 10% rule and by the time the race was on the calendar I wondered if I really needed it anymore.
Then it got cold in December and I didn’t run for 30 days. Then we got two shorts weather days back to back in December I jumped off the couch and ran 22 km. And right after my knee was worse than ever. So I did the exercises Gill sent me and bought a bigger brace. I wore it for every km this running season, until this past weekend. And my knee stayed pretty good. I felt that it helped even though the reading I had done suggested it wasn’t anything other than a phycological effect. The past two weeks my knee has been hurting again and on my Sunday run it was excruciating and I took the brace off, it felt better, I took it easy and ran my first 3.5 km without a brace in two years. Today I went out and with new shoes (stay tuned for a review) and last year’s little brace.
So what do running blogs say about braces
Not a whole lot, maybe that they don’t officially help but some runners feel they do. That runners knee originates from the hips maybe and that shoes are important and that’s about it. You’ll read a few theories as well that it’s really about weak hips and that the the patella or knee cap tracks outside where it should causing pain, but that might not be the case. Also one guy on reddit bought a brace for his bad knee and qualified for Boston 6 weeks later, where do I get that brace? There isn’t clear direction and I still have so many questions. Do they work? Do they just keep you injured like Gill said? How do you know when/ if you can stop wearing them? Was it my not so great running shoes keeping it sore? For my hours and hours of reading that’s what I got. So I decided to look into it and I figured I might as well write it down and share.
What does scientific literature say about knee braces?
Dating back to the 1980’s and 1990’s studies suggested that there was no significant difference between based and non braced runners (1) and that has yet to be disproven (5). Many studies, as well as runners and the start lines of races suggest that more than a few runners find that they help anyway. But 25% of athletes diagnosed with runners knee or patellofemoral pain syndrome will stop participating in sports because of it (2). There is an idea that abnormalities in bone marrow or cartilage cause runner’s knee. The thing is even though it is occasionally seen in runners with pain its just as regularly seen in people without pain (3). But there may be some truth to the ideal that patella maltracking could be to blame. Incidence of bisect offset, congruence angle, increased lateral translation (maltracking), lateral patellar spin, and a tendency toward increased lateral tilt are more common in MRI imaging in people with knee pain then those without (4). Certain muscle imbalances are also more common in patients with runners knee such as weakness in the quadriceps, vastus medialis muscle and vastus lateralis muscle both muscles that originate in the hips (5).
But can braces cause you harm? Well yes they can. When the straps of a knee brace are tightened more than suggested there is no corresponding reduction on the side to side motion of the knee joint. But tightening the straps increases the pressure on the soft tissue of the thigh and leg. This can lead to decreased blood flow, muscle oxygenation and lead to earlier fatigue in the muscle. This is true at rest and can lead to abnormal levels durning exercise. (6) Since muscles might be partially to blame wearing a brace that cuts off blood flow might make it worse. So maybe there is some truth to Gill’s words that braces just keep you injured.
Surgical interventions are a mixed bag at best right down to not advised unless as a last resort. Physiotherapy is recommend as a best practice currently and the only treatment known to give long term, sustained improvements. Specifically exercises targeting the hip external rotator and abductor muscles and knee extensor muscles (5). So here is the answer to my first question, how often and for how long do you preform the exercises? The answer is for 6 weeks, and the exercises should be conducted two to four times daily with 10 repetitions per exercise session (7). There is good evidence that taping (both classic and Kinesio) works but also that sham taping has a fairly robust phycological effect and there are not long term benefits (5). Braces have been shown to change patella tracking when but there has been insufficient evidence to recommend their use. But… recently a study, a really good study, found that there was a great positive effect initially in pain reduction but that has almost entirely gone away after a year (8). The recommendations of an expert panel of researchers into runners knee, yes there is such a thing, actually favour taping over knee braces but suggest that there is a place for braces in the short and medium term, both recommendations stress that this should be as a supplement to physical therapy (9).
Question number two, do knee braces work? Well we can find that information within the scientific literature too and the answer is an oddly definitive, yes and no. Yes braces, much more so than pressure sleeves and slightly more than knee straps do limit the side to side movement and forces generated within the knee that lead to runners knee. But braces alone are not sufficient to return to normal tracking or cure the condition. What braces do wonderfully is increase contact with the knee cap and the knee which leads to pain reduction but is not enough to get long term relief (10). In the short term braces are effective in reducing pain as is taping but the consensus is that the best way to go forward is exercise therapy. Since generally physiotherapy is recommended and then taping before braces are to be used there is no recommendation on the length of time braces should be used except to say in the ‘short term’ that I could find. And trust me I looked.
So what does this all mean?
Well this week I was out for a terrible run. My knee has been acting up lately since I’ve upped my milage in preparation for a half early next season. Also I did a few private yoga sessions in the last few weeks. Every time I stopped to adjust my brace, which was a lot since my knee was killing me, the auto-pause on my app stopped my run. After 2 km I was fed up and I took off my brace, turned off auto-pause and ran 3.5 km, brace free. Since then I’ve returned to my little strap from last year and decided I needed to look into all this.
So as my mom likes to say… I’m not the kind of doctor that helps people (joking) but here’s what I’m going to do going forward. I’m taking a break for a month from yoga classes with all those physical corrections and practicing gently at home. Most importantly of all do those exercises and four times a day, not once as I was doing before, going forward. I even drug my second sucky yoga mat into the living room floor from the back of the spare bedroom closet. I’m going to be running brace free, but bringing my strap incase the pain gets bad. And if I’ve used a brace in the last 6 weeks the exercises continue. I think that even though I got good advice last year I was looking for a quick fix. Putting on a knee strap last year reduced my pain and I went with it. When it acted up again I went for a bigger brace. But as the literature suggests that effect is typically gone within a year, 16 months in my case. But braces can get me over the hump should it act up again when my milage goes up again in the future. Also tell me more about patella taping…
Hindsight is 20/20 as they say but like most runners out there I just wanted to keep running consequences be dammed. I paid too much attention to the blogs and posts that said what I wanted to hear, even though this post from early this year suggests I knew better. Looking back I feel like I should have done this sooner, but if I was running, what did it matter? In retrospect I feel like I missed out on the opportunity to actually make myself better rather than just keep running by going the brace route.
Check out the peer reviewed studies below, a lot of them have free PDF’s available online if you don’t have access to a university library system. What are your experiences with knee braces and are they similar to mine?
- Effects of a functional knee brace on the biomechanics of running. Devita et al., 1992. Medicine and Science in Sports and Exercise
2. Unsatisfactory long-term prognosis of conservative treatment of patellofemoral pain syndrome. Rathleff et al., 2012. Ugeskr Laeger
3. Structural Abnormalities on Magnetic Resonance Imaging in Patients With Patellofemoral Pain: A Cross-sectional Case-Control Study. van der Heijden et al., 2016. American Journal of sports medicine.
4. Which patellofemoral joint imaging features are associated with patellofemoral pain? Systematic review and meta-analysis. Drew et al., 2016. Osteoarthritis Cartilage
5. Patellofemoral pain in athletes. Petersen et al., 2017. Open access journal of sports medicine.
6. The effects of functional knee bracing on muscle function and performance. Styf. 1999. Sports Medicine
7. Patellofemoral pain syndrome. Petersen et al., Knee Surgery, Sports Traumatology, Arthroscopy. 2014.
8. Evaluating the potential synergistic benefit of a realignment brace on patients receiving exercise therapy for patellofemoral pain syndrome: a randomized clinical trial. Petersen at al., 2016.
9. 2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 2: recommended physical interventions (exercise, taping, bracing, foot orthoses and combined interventions). Crossley et al., 2016 British Journal of Sports Medicine.
10. Update on Rehabilitation of Patellofemoral Pain. Dutton et al., 2014. Taping, prevention and rehabilitation.
11. The ‘Best Practice Guide to Conservative Management of Patellofemoral Pain’: incorporating level 1 evidence with expert clinical reasoning. Barton et al., 2017, British journal of sports medicine.
Sweat Sweetly 