Runner’s Knee: Beating the Injury
On Sunday, August 25 I went to Whistler, British Columbia to be a team Physiotherapist for a group of three athletes taking part in Ironman Canada. A 3.8KM swim, 180 KM bike, and 42KM run. The sheer determination and strength, both physical and mental, of the 2800 + contestants is absolutely amazing. Training and competing in such an intense race requires the proper “pre-hab” and re-hab. In the following weeks I will go through the 4 major injuries encountered by these athletes in the marathon portion of their race.
Week 1: Runner’s Knee
What is it?
Runner’s Knee, clinically known as Patellofemoral Pain Syndrome (PFPS), is a common complaint of injured runners. It is the irritation of the cartilage between the patella (knee cap) and the underlying femur. Typically PFPS is an overload injury caused by faulty biomechanics.
How does it present?
PFPS or runner’s knee typically presents itself during or after prolonged runs, while descending stairs/walking downhill, or during prolonged bouts of sitting. Often times there is no pain when palpating the area, and if swelling is present, it is often mild in nature. If there is marked swelling, likely there is additional injury to the surrounding tissues.
Clinically, I often see a deficit in Gluteal and inner Quadriceps strength (Vastus Medialis Obliquus, aka VMO), as well as faulty tracking of the patella throughout knee flexion and extension. A quick test is to perform a single leg squat, if the knee approaches midline and the runner is unable to maintain a stable pelvis it is likely that strengthening of the VMO and Gluteal muscles (abductors and external rotators of the hip) is required.
How to treat and manage Runner’s Knee (PFPS)
In acute cases of runner’s knee, stop exercise and ice to decrease swelling of the affected area. Specific exercise to target and isolate the muscles that require strengthening is needed. This article will focus on strengthening the hip abductors/external rotators, as well as the VMO. Once the runner can isolate the muscles correctly, then more functional exercises can commence in order to expedite the return to running.
Exercise #1 : Isolating the VMO
Sit on the floor with the distal thigh (underneath the thigh above the knee crease) resting on a foam roller (if you do not have a foam roller, filling up an empty 2 L plastic bottle with sand works just as well). The knee should be bent and relaxed at an angle around 30 degrees. Place a ball between the legs, such as a soccer ball or football that is large enough to maintain proper leg alignment (the hip, knee, and 2nd toe should be in line). Allow the big toe to point slightly outwards. While squeezing the ball between your legs, slowly extend the knee to full extension. You should be able to feel the VMO harden on the inside of the distal thigh. Hold for 6 seconds. Slowly bend the knee back to resting position. 3 sets of 12 repetitions.
Exercise # 2: Isolating the hip abductors/ external rotators
Lay on your side with hips in neutral position*. Bend the knees at a 90-degree angle and stack the heels on top of each other. Keeping the heels together, bring the top knee away from the bottom knee. Do not allow the hip to fall backwards or the lumbar spine to twist. Once at end range (you will feel as though you can not bring the knee up any farther without the hips wanting to move), hold the contraction for 3 seconds. Slowly lower the knee and repeat. 3 sets of 12 repetitions per leg.
*Common error for this exercise is to have the hips flexed.
Functional Progression:
Exercise #3
Place a theraband (any elastic will work) around your knees that provides moderate tension when your feet are shoulder width apart. Maintain a neutral position of the foot and at all times do not allow the knee to move inwards towards the midline of the body (think engaging the same muscles as in exercise #2). Bend the knees and hips slightly and maintain a ¼ squat position. Sidestep 15 paces in a slow and controlled manner being careful of the knee alignment (middle of patella in line with the second toe). Repeat in the other direction. 3 sets, each direction.
Exercise #4:
Stand close to a wall parallel with it. The leg to be strengthened will be furthest away from the wall. Place an exercise ball between the wall and your hip. Bend the knee closest to the wall so that the foot is off the floor. Ensure the outside foot is in line with the knee and hip. Slowly bend the knee and lower yourself into a single leg squat. Ensure that the knee remains in line with the second toe. If at a point your knee starts to move inwards, stop and repeat the movement prior to the ‘breaking point’.
Can you continue to run?
Initially a break from running is advised as you begin the therapeutic exercise and physiotherapy. Cross training such as cycling, elliptical, and swimming are good options to maintain aerobic fitness and keep the knee moving while rehabilitating as long as these activities are pain free. Once the acute stage is over, it is recommended a gradual increase in running frequency, intensity, and duration. Since every case of runner’s knee is different, it is important to consult with your Physiotherapist prior to progressing to the next stage of your rehabilitation.
By physiotherapist Jonathan Tom-Yew
