Common Running Injuries: Patellofemoral Pain Syndrome (Runner’s Knee)

Millions worldwide embrace running as an easily accessible form of physical fitness, myself included. There is no argument about the health benefits that consistent running imposes on your body, which is why in recent times endurance running has become the number one activity for persons seeking a better quality of health and wellness. However, it is estimated that between 30-70% of habitual runners develop some type of repetitive stress injury on a yearly basis. In this series of posts, I will provide an overview of the most common injuries suffered by runners with the intent to increase awareness of signs and symptoms, provide simple home treatment techniques, and promote preventative habits to employ so that you can get the most out of your running. We start with the dreaded Runner’s Knee or patellofemoral pain syndrome.

What is Patellofemoral Pain Syndrome (PFPS)?

PFPS is pain in the knee that is caused by degradation of and/ or irritation to the cartilage on the underside of the kneecap.

Symptoms

Symptoms include pain in the front of the knee that is usually flared up when the knee is in a bent position for a prolonged period of time. Squatting, ascending/descending stairs, running, and jumping/landing are common activities that will flare up knee pain. In more severe cases some experience popping, grinding, or catching in the knee with any type of physical activity/knee movement.

Causes

To understand the cause of PFPS, you have to fully understand the mechanical nature of the condition. The root cause is cartilage on the underside of the kneecap becoming irritated and inflamed. So you need to ask the question “How does this cartilage become irritated?” The answer is multi-factorial.
1. Tight Quadriceps: The quadriceps muscles come together to form the superior/inferior patellar tendons and the lateral/medial retinacula of the knee. Basically, we have all this tissue in the front of our knees that is directly affected by the quadriceps. If the quadriceps are tight, these tissues are tight. When these tissues are tight, the kneecap becomes restricted and compressed. That means that the underside of the kneecap (the area with all that cartilage) becomes approximated into the distal femur. When movements at the knee are performed and the kneecap is in this restricted/compressed state, the cartilage will be more susceptible to irritation.
2. Weak Quadriceps: Tight and weak muscle goes hand in hand. When you have a pathologically tight muscle, the muscle becomes weaker because it is less able to function and participate in the kinetic chain properly. Likewise, when you have a pathologically weak muscle, the muscle becomes tighter to create a false sense of stability, especially when there is more demand placed on the muscle. Therefore, if your quadriceps are weak, they will tend to be tighter. And we already know how tight quadriceps affects the cartilage under the kneecap.
3. Misalignment of the Patella: Not many people realize this, but the kneecap is vital to proper functional motion of the knee. For a variety of reasons, the kneecap can come out of alignment. More often than not this coincides with a patellar tracking disorder, which is an imbalance in the knee that causes the kneecap to tilt/shift out of position with knee motions. The abnormal sifting/tilting of the kneecap can cause some areas of the kneecap to approximate on the distal femur, creating irritation to the cartilage on the underside of the kneecap.
4. Weak Glutes/Hips: Weak glutes and hips can lead to a myriad of musculoskeletal conditions, including PFPS. The weaker the glutes and less stable the hips are, the more the distal muscles will be called upon to compensate. This will lead to overutilization of the quadriceps to stabilize, especially with repetitive weight bearing activities like running. When muscles are overused, they will be in a state of increased tightness, thus creating increased load on the kneecap and susceptibility to irritation.

Treatment

Proper treatment of PFPS involves identifying and addressing the root causes to ensure proper rehabilitation and prevention.

1. Promote Flexibility of the Quadriceps/Hip Flexors

IT Band Release

Lie on the side you wish to release.
Place the foam roller under your bottom leg halfway between your hip and knee.
Slide your leg up and down along the foam roller, moving it from the top of the knee to the base of the hip.
Try to work over the more tender areas as you can tolerate.Repeat in 30 second intervals for two minutes.
To focus on a specific area of the IT band, locate the most tender area with the foam roller and stop.
Bend your knee at a 90 degree angle, and then straighten. Repeat motion of bending and straightening knee for 10-15 seconds.
You may repeat this with other areas along the vastus lateralis.TFL Release

Quad Release

Lie with the front of your thigh on the foam roller half way between the knee and the base of the hip.
Slide your leg up and down along the foam roller, moving it from the top of the knee to the base of the hip. Try to work over the more tender areas as you can tolerate.
Repeat in 30 second intervals for 2 minutes.
To focus on a specific area of the quads, locate the most tender area with the foam roller and stop. Bend your knee at a 90 degree angle and straighten.
Repeat motion of bending and straightening knee for 10-15 seconds.
Repeat on other areas of the quads.

Functional Hip Flexor Stretch

Begin in half-kneeling position with back leg on a soft pad or pillow. Forward knee should be directly above ankle with a 90 degree bend in knee.
To begin stretch, shift weight forward to lunge into forward knee while keeping torso tall and pelvis tucked under.
The stretch should come from your pelvis and you should feel it in the front of the hip. Don’t lean forward with your torso.
To get a deeper stretch,bring the arm on the same side as your back leg up over your head, then side bend and twist your torso away from the leg being stretched.

Standing IT Band Stretch

Stand with both feet flat on the ground. Cross one leg over the other, keeping your back leg straight.
Bend and twist away from the center of your body toward the heel of your back leg until you feel a stretch. Hold.
Repeat on the opposite leg.

2. Strengthen Quadriceps

Straight Leg Raise

Lie on the floor with back flat (no arch). One leg should be straight and one leg should be bent with your foot flat on the floor.
Tighten your quad, toes pointed towards you,and slowly bring your leg up to the height of the knee of your opposite leg.
Hold and repeat.

VMO Squat

Stand on one leg, drop other leg down on to the toes like a kickstand, slack in the knee, weight through the heel . All weight should be on one leg at a time.
Squat down while forcing knee out, shifting weight to ball of the foot then back up. Repeat
Keep knee forced out throughout exercise.

3. Strengthen Glutes/Hips

Bridges

Lie on your back, keep entire back flat on the floor with knees bent at 90 degrees. Feet should be flat on the ground with weight through the heels. Push through the heels and bring glutes off the floor into a bridge.
Hold for 3 seconds at the top of the motion.

Inner Thigh Squats

Place feet shoulder width apart with your toes pointed out at a 45 degree angle. Weight should be placed through your heels.
As you begin to squat, bring your hips back like you are sitting in a chair that is too far behind you.
While squatting, try to move your knees out. Go as low as you can, then push back up through your heels, repeat.

90-90’s

Lie on your right side with your right hip and your right knee each at a 90 degree angle and your left leg directly above your right leg.
Position One: Keep your left foot flexed (toes towards you) and lift your left leg up towards the ceiling, keeping the arch of your foot parallel to the ground.
To maintain proper posture, make sure your left hip is stacked directly on top of your right one. Avoid rolling backwards. Repeat 10 reps.
Position Two: Keep your left foot pointed (toes away from you) and lift your left leg up towards the ceiling, keeping the arch of your foot parallel to the ground. Maintain proper posture.
Position Three: Keep your left foot flexed (toes towards you) and rotate your leg so that your toes turns towards the ground on a count of two. Return back to starting position. Maintain proper posture.
Repeat for 10 reps.
Repeat on other side of body.