by Kaylie Wilson
Hi, my name is Kaylie Wilson and I am a Physical Therapist at Momentum Health in Calgary, AB. I have been practicing for almost 7 years in private orthopedics, so I have seen a lot of different injuries! I am also an avid runner and have been for 15 years. I have competed in 2 half marathons, and 1 full marathon, though currently, all my runs are with my very active border collie, Jackson. Due to the present COVID-19 pandemic, there are more people taking up running with gyms being closed, so now would be a good time to discuss common running injuries. The first one I am discussing in this week’s blog is Patellofemoral Pain Syndrome, otherwise known as Runner’s Knee.
What is Patellofemoral Pain Syndrome?
Patellofemoral Pain Syndrome (PFPS) is pain around the patella (knee cap) and anterior knee. It can range from a dull ache to throbbing, sharp pain. Typically, the aggravating factors for PFPS are running, stairs, squatting, jumping, or any weight-bearing activity that involves bending the knee. Occasionally pain can be constant, but typically it only comes on with activity. PFPS does not typically have a mechanism of injury, most people will report onset of pain after running for a period of time.
What causes PFPS?
Research has theorized that the medial structures of the patella are put under stress secondary to decreased internal rotation control from the hip, and excessive use of the inner thigh muscles during activity. Since PFPS is a dynamic injury, generators of pain won’t necessarily show up on diagnostic imaging as these are pictures taken with the limb in a static position.
Though there is not one specific exercise or method to prevent PFPS from ever happening, there are steps one can take to reduce the risk of developing anterior knee pain. If you are a beginner to running, start gradually with intervals (running/walking) that have longer periods of walking (2 or 3:1 ratio). Don’t be too concerned with distance when you’re starting out, instead focus on closing the gap on your walking/running intervals.
It is also important for runners to include strength training as part of their weekly regime. Strength training can help to increase power output (for example, running up a hill during your run) and improve running economy overall. Strength training also creates load on tissue which can help our knees adapt to various forms of stress, like running. Often in PFPS, it is a decreased tolerance to load on the tissue around the knee that leads to excessive stress and pain, but with gradual loading and added strength training, the tissue can adapt.
Another way to change load on your anterior knee is by increasing your step count during a run (cadence). To measure your cadence, count how many times your feet hit the ground in one minute. Once you have this value, try to increase to number of foot contacts per minute by 5-10%. The important thing to remember is cadence is not an increase in running speed, you can increase your foot contacts without running faster.
What if I already have knee pain?
My first recommendation is to have your knee pain assessed by a physiotherapist to assure it isn’t something more serious. At this time, it is difficult to go into a clinic to be assessed, but many clinics are offering Telehealth, which is physiotherapy via a webcam. The good news is most overuse injuries from running can be managed with a supervised and gradual exercise program, all of which can be done with Telehealth.
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