Top 5 Running Injuries: Patellofemoral Pain Syndrome
Welcome to the 5th and final installment of our blog series of the five most common running-related injuries we see in our clinic! If you haven’t seen the prior posts, be sure to check them out for some light reading.
“Patellofemoral Pain Syndrome” (PFPS) is a catch-all diagnosis that typically refers to pain in the front of the knee or around the knee cap. In other words, this diagnosis does not indicate the pain generator, only the location of the pain. Pain in this location can be caused by the quadriceps muscles (or other muscles of the thigh), the infrapatellar fat pad, or the patellar tendon.
PFPS is characterized by knee stiffness in the morning or after a period of inactivity (i.e. sitting for a long period of time that improves with movement. The pain may increase with downhill running, long runs, going up or down stairs, or squatting/lunging. The discomfort is typically a dull, aching, or “tight” feeling, and may be difficult to localize at times. Tenderness and point pain of the patellar tendon is indicative of a tendinitis or tendinopathy, and the treatment for this issue will be slightly different.
What causes it?
The knee joint is primarily a “hinge” joint- while it is able to move slightly in other directions, it primarily has 1 direction of motion: bending and straightening. Therefore, the forces across the knee joint depend heavily upon the hip and foot, which are able to move in more planes of motion. Oftentimes, knee pain is due to faulty mechanics of the hip or foot, particularly with fatigue as the distance of a run increases.
As with most running injuries, a rapid increase in training, change in terrain of running, life stress, daily and training nutrition, and recovery from workouts should be considered as potential causes, as well.
So, what is a runner to do?
While hip and pelvic girdle weakness play a major role in many running injuries, it is of utmost importance in the treatment and prevention of knee pain in particular. Proper alignment of the leg with running is key to avoid excess strain on the knee and patellofemoral joint, and this depends largely on the ability of the runner to control the hip and trunk. Thus, the treatment of PFPS is directed toward strengthening the abdominal muscles, hip abductors, and hip external rotators. It is also important progress exercises to target these muscles into the standing position, and practicing good hip, knee, and ankle alignment throughout. Examples of said exercises are: single leg deadlifts, single leg squats, and lunge/split squats, to name a few. It can be helpful to perform these exercises in a mirror for feedback of alignment.
The other piece of this puzzle is the foot. As a runner, if you overpronate or have difficulty controlling pronation, this imparts a rotational force of the tibia (shin bone) and thus can change the dynamic alignment of the leg while on one foot, potentially increasing the strain of the patellofemoral joint. Improving foot strength and endurance can be a simple as completing single leg exercises, balancing on one leg, or simply walking barefoot as much as possible. I’ve heard stories of professional runners who practice their single leg balance while brushing their teeth or cooking! Again, it is important to be intentional with these exercises, focusing on the prevention of arch collapse (pronation) while on one foot.
PFPS is often accompanied by trigger points, or tight areas of muscle, in the quadriceps, glutes, and calves. Utilize a foam roller or lacrosse ball on these areas to decrease potential pain referring from these areas. Spend extra time on the quadriceps, as knee pain referring from these muscles is very common, as evidenced by the pictures below.
Lastly, running with a lower cadence causes increased time spent on the ground, requiring the runner to control single limb stance for longer. This is not only problematic due increased overall force absorbed by the body, but also increased energy expenditure. Increasing cadence (the number of strides you take per minute) as little as 5-10% can make a difference and decrease knee pain. Use a metronome or other phone app (there are a few, some even find music to match your desired cadence!) to help train yourself to feel the new cadence. The change will likely feel more taxing initially, but it will pay off in the long run (pun intended).
Need more specific guidance? We have created a Do-it-Yourself program for the treatment of Patellofemoral Pain Syndrome. It includes detailed instructional videos, a week-by-week corrective exercise routine, and other self management tips. Check it out in our store.
Keep going, you got this!
Kacy Seynders, PT, DPT