Patellofemoral Pain Syndrome

Runner's Knee Part 2: Hip & Ankle Mobility - How It Relates To Patellofemoral Pain Syndrome

In part 1 of our runner’s knee series, we discussed the specific anatomy involved, how and why we experience pain over/in the front of the knee, and most importantly, how running, and specifically downhill running, can hasten your onset of patellofemoral pain syndrome.  ->Read Part 1 Here <-

Today, in part 2, we are going to move away from the knee and look at the friendly joints above and below.  As we know, and you will soon find out, the hip and the ankle are in control of the knee and more times than not, pain at the knee is caused by faulty mechanics, immobility, or strength and stability deficiencies at either or both of these joints.  Read on!

HIP FUNCTION IN RUNNING AND ITS RELATION TO KNEE PAIN

So that we have a starting point, we are going to travel from the hip down.  Mainly because it is more commonly the culprit of running associated knee pain (my own clinical experience) but also because it is the bigger joint with more opportunity for complications.  

To help explain how the hip acts on the knee, I commonly tell patients in the clinic that we have no ‘knee muscle’, but that everything controlling the knee, comes from the hip.  While this is not exactly true, we have some very important muscles like the VMO and popliteus that act very strongly on the knee while not originating from the hip, but hopefully, you can read through that and see my point here.  Control at the knee is primarily governed by the hip.

When we encounter a runner with patellofemoral pain, we will ‘treat’ the knee...but the majority of our work is spent on improving hip mobility, strength, and stability.  What we find is that issues here can lead compensations, deficiencies, and imbalances that contribute to Runner’s Knee.

IT band tightness pulls on the patella causing it to track laterally, or to the outside.
Hip tightness can cause an anterior pelvic stance.  This can inhibit and tighten the hamstrings causing an altered gait that is ‘quad heavy’.  This tilt and tightening can lead to altered mechanics at the knee and also lead to patellofemoral pain.
Hip drop due to a weakness of the glute muscles can lead to  what we are now calling the Miserable Malalignment Syndrome.
 
 

Let's talk about that last one for a minute as this is becoming more and more common in running associated knee pain.  Miserable Malalignment Syndrome is the name now given to the cascading breakdown when the hip and ankle fail.  Essentially, when our foot is planted, the glute medius muscle of the foot planted holds our pelvis level.  When this weakens, the hip drops, causing the other side to respond. This response causes an inward rotation of the femur bone, an outward rotation of the tibia (shin bone) in an attempt to compensate, and lastly, a turning out of the foot resulting in a crashing in of the inside of the foot.  

Guess which joint is in the middle taking all of that rotation torque?  

I explain this in the video and picture below.  Now, this condition got its name, not necessarily for runners, but for those who sit too much and exhibit the same pattern, but it fits here.  If anything, this helps explain how important our hip mobility and strength is to the health of our knees. If you remember, as runners, we load the knee with 5-6 times our body weight with each and every step.  Rotation in a joint NOT designed for rotation is destined to cause problems.

ANKLE FUNCTION IN RUNNING AND ITS RELATION TO KNEE PAIN

AnkleDorsiflexion.png

Now that we better understand the hip and its relation to knee pain, let's travel down the road a little to the ankle joint.  Without getting into the kinematics of the ankle and the joints that make up this complex area of the body, let's just try to understand one thing...DORSIFLEXION.

Dorsiflexion is your ability to bring the top of your foot toward your shin.  When we run, dorsiflexion allows us to strike the ground, react, and toe-off properly, pushing from our big and second toes.  To help understand this, lets picture what poor dorsiflexion looks like. The next time you are walking around, look for someone who walks with their feet turned outward.  What is usually happening here is that their hip tightness causes their posterior hip muscles (glutes, piriformis, etc.) to pull on the femur, resulting in an outward turned leg and foot.  And...Unless they rode in on a horse, they are not walking with their kneecaps over their feet in this position which leads us to what we just discussed, the foot crashes inward, the kneecap points a different direction of the foot, and we now have pain.  You can now imagine that there is no way this person is walking properly, meaning they are not actually toeing off correctly, but the inside of their foot, now...IMAGINE THIS PERSON RUNNING.

You may have realized that poor ankle dorsiflexion and the lack of hip mobility and stability can cause the same problem.  The truth is, they tend to run together. While we will always treat any and all problems presented to us, it is my job to find the key that unlocks the whole system and more times than not, it is the hips!  

 
 

 

TIME TO REVIEW WHAT WE LEARNED TODAY

  • Most of the muscular control of the knee comes from the hip.  Lack of mobility and strength here can contribute to patellofemoral pain syndrome.  

  • Lack of ankle dorsiflexion (the ability to bring the foot toward the shin) can cause outward rotation of the foot and undue rotational strain on the knee.  

  • Issues at the hip and knee can lead to what we are now calling the Miserable Malalignment Syndrome.  Essentially, when we run, our hips drop, causing an inward rotation of the femur, a counter-outward rotation of the shin bone, turning out of the foot and crashing in of the inner foot leaving the stress on the knee.  

  • To properly address runner’s knee, we must address these deficiencies at the hip and ankle.

 

Once you have digested the information we discussed in these last two articles, keep your eyes peeled for part 3 next week as we will begin discussing what to do if you already have patellofemoral pain and when you should seek care so you can continue, or return to, training.

Read Part 3 Here -->


Dr. Reheisse is a Board Certified Chiropractic Sports Physician practicing in Cottonwood Heights Utah. Revive Sport & Spine provides evidence-supported chiropractic care and conservative sports injury management.

Runner's Knee Part 1: What Is Patellofemoral Pain Syndrome (PFPS) And Why Is It Common In Runners?

If you have been running for any period of time, then you have most likely had a run in with, or are currently battling, Patellofemoral Pain Syndrome (PFPS), or Runner’s Knee as is better known in the endurance community.  PFPS is one of the most common causes of knee pain in runners but is also one of the most challenging conditions as the specific cause can be elusive. Furthering the challenge, Runner’s Knee itself has been used as a blanket diagnosis when runners present with any kind of knee pain, especially to clinicians unfamiliar with runners and running mechanics. 

Our goal through this series is to help runners of all abilities better understand their knee pain, its cause, and how to self-treat and prevent future occurrences.  Additionally, as a provider based in Utah, we are the land of abundance when it comes to downhill races.  This causes a sharp increase in PFPS cases that come through our office during the fall marathon season.  

 

What Is Patellofemoral Pain Syndrome?

 

Let's start with basic anatomy.  The Patellofemoral joint is made up of the Patella (Knee Cap) and the Femur.  When we run, squat, or navigate stairs, the patella tracks, or glides, through a grove on the femur as the knee bends and straightens.  Almost always, this is a pain-free movement.

 

 

Note: There are different shapes of this joint that can cause mal-tracking of the patella and abnormal wear patterns that can cause pain.  Also, body mass plays a role in the loading of this joint as well. In an attempt to keep this article simple, we will not discuss this further as many resources are available on this topic.

Now that we understand the basic anatomy, let's define Patellofemoral Pain Syndrome.  

According to the Patellofemoral pain consensus statement, given at the 4th international Patellofemoral Pain Research Retreat, PFPS can be defined as ‘Pain around of behind the patella, which is aggravated by activity that loads the patellofemoral joint during weight bearing on a flexed knee (as in running) and could included but not necessarily, crepitus, tenderness to palpation, effusion, and pain upon rising or straightening the leg after sitting.  

While this sound very general and vague, it does help us eliminate some of the other common running knee injuries as most have their specific criteria for diagnosis.  Simply put, Patellofemoral Pain Syndrome is a pain over, under, or around the kneecap that is aggravated by running.

 

How Common Is Runner's Knee & What Are The Signs And Symptoms?

How do you know if you are truly dealing with patellofemoral pain syndrome?  Honestly, that is where physicians come in, but you can get a good idea yourself just by understanding its presentation.  We have already discussed that it typically presents as pain over, under, or around the kneecap that is aggravated by bending of the knee, but who is at greater risk?

Those at risk include young adults, more commonly during times of growth or during activities that require repetitive movements (running).  According to a 2016 issue of JSPT, 75% of patients have tenderness around the patella, the onset is usually gradual at the anterior, or front, of the knee, and pain occurs during movements that increase stress along the joint.  

It should also be mentioned that Runner’s Knee is notoriously stubborn, meaning rest alone typically does not help.  A structured treatment and rehabilitative action plan need to be in place to allow timely recovery and prevent future occurrences.  

qangle.jpg

To better understand your risks as a runner, almost ¼ of all knee complaints presenting to an orthopedic, sports chiropractic, or PT office are PFPS with almost double the number of female cases as male, most likely due to Q-angle and knee valgosity during running.

 

What Causes Patellofemoral Pain Syndrome?

Deep breath...

Before we jump into how running relates to Patellofemoral pain syndrome, so much that it is called ‘Runner’s Knee’, let's talk about the normal stress of the joint.  The patellofemoral joint is designed very well and is suited to handle quite a bit of stress. Just think about the weightlifter that can squat a small truck or the guy down the street who seems to run an ultramarathon every other weekend.  Our knees are designed for load, yet, as in many other things in life, genetics and care for oneself have a great impact on how well we recover from that load.

As we study patellofemoral pain syndrome, we understand that load compounds and becomes too much.  This excess in stress can wear away the protective layers around the joint, causing pain during common movements.  As runners, we can understand that on each and every step, we are loading the knee joint, thousands of times each and every run.  

We should mention that while running, we load the knee with 5-6 times our body weight each and every step.

Hopefully, something just clicked and you now realize why you need a day off each and every week….sometimes two, to allow for proper recovery and regeneration of your tissues.  As runners, we can not continue to pound the pavement and climb the trails, day after day, and expect our bodies to cooperate.

Now, where does this stress come from?  If we go back to our anatomy, we see that the powerful quadricep muscle group attaches to the patella through a much smaller quadriceps tendon, which then dissipates load and tension through an even smaller patellar tendon on the bottom of the patella.  Over time, the quadriceps can become tight, causing abnormal tension, and movement of the patella over the femur.  When we run, we drag the patella across this groove thousands of times and if we have dysfunctional movement, this can cause a problem.  

Another common cause of tracking issues is the all-to-familiar IT band tightness.  If you are a runner who has had a quarrel or two with IT band syndrome, then chances are this could be a contributor to your Runner's Knee.  To better understand this, we know that the IT band attaches to the lateral side of the knee (outside) with attachments directly on to the patella and the lower leg.  Tightness here can pull that patella laterally, resulting in maltracking through the groove, furthering wear, breakdown, and pain. Now, we can’t just blame this on a tight IT band as tracking to the outside could be from a weakness of the medial stabilizing muscles of the thigh.  

Not to go to in-depth with running mechanics.  The quadriceps should not be the primary driver in runners, but some have less than ideal form while others just absolutely love downhill racing!

As a Utah based physician and now Utah based runner, downhill races are the thing.  

As a side thought I have shared with patients.  I cringe but slightly enjoy talking with out-of-towners who think they are going to come here, run a race with a 3000 ft drop, and just breeze to a new marathon PR.  I always give warning that if you do not control your tempo and stride, your quads are going to blow up and you will either have a terrible race or have terrible knee pain the following days and weeks….often both.   

Back to the mechanics.  During downhill running, our quadriceps no long absorb shock and help move us forward, they begin to slow us down and perform a similar job of eccentrically bracing for impact and preventing the femur from translating too far forward over the tibia (shin bone) while maintaining some kind of control medially and laterally.  This is very taxing on a muscle.  Imagine doing 100 squats, but instead of just pushing up, you have to do a slow 20-second descent into the squat position, essentially what we call a ‘negative’ movement. This is a different strain on a muscle, one that has to be trained and if you do not practice downhill running, some of the races we have will eat you alive!  

Now that I’m off of my soapbox.  The repetitive nature and load that running puts on a knee can quickly cause patellofemoral pain.  Downhill running is a major catalyst to Runner’s Knee pain!

 
 

How Do We Address Runner's Knee To Keep You Running?

So, how do you treat patellofemoral pain syndrome?  Well... we first have to determine the cause. If you are a runner, it is not as easy as saying running is the cause.  The intricacies of the running mechanics are more likely to be at fault, this is where a thorough assessment comes in.

Depending on the providers, you could be told to stop running for a while, while another trained in treating runners will try to find the cause and develop a plan around you continuing to run. Either way, the easiest explanation of a patellofemoral pain treatment plan consists of 3 things: Offload, Rehabilitate, & Reload.

Offload:  Is the pain so bad that you can not take more than a handful of steps without some kind of pain?  This may require some time off from running. For most, if you address the pain early, a modification in your training program is usually necessary.  Typically we will scale back your intensity, volume, or both while you are working through the rehabilitative phase.

Rehabilitate:  What is the primary cause of your patellofemoral pain?  Once we can determine your cause; running form, hip strength, ankle mobility, training volume, downhill running, etc., we can develop a plan around this, your goals, and your races.  

Reload:  While we don't want to completely offload an injury if possible, we find that maintaining some of the familiar load (in this case, pounding the pavement) placed on the muscles, joints, ligaments, and tendons can speed healing.  As we work back up from an injury, care, caution, and discipline must be placed on progressing slowly, even in we are feeling great.  

 

Let's Review What We Have Learned So Far.  

  • Patellofemoral pain syndrome is one of the most common sources of knee pain in runners, so much so it is also called Runner’s Knee.

  • Patellofemoral pain syndrome is characterized by pain over, under, and around the patella, or kneecap, that is aggravated by activities such as running that load the patellofemoral joint in a repetitive manner.

  • Runner’s Knee is most commonly an overuse condition.  

  • During bending of the knee, the patella glides, or tracks, through a groove in the femur.  Tight muscles, excess load, overtraining, etc. can cause dysfunction of this movement, leading to patellofemoral pain.  

 

Stay tuned for more information (than you could ever want or need) on Runner's Knee, its cause, what you can do for it, and when it is time to seek help so that you can continue to run toward your racing goals.

Read Part 2 --->


Dr. Reheisse is a Board Certified Chiropractic Sports Physician practicing in Cottonwood Heights Utah. Revive Sport & Spine provides evidence-supported chiropractic care and conservative sports injury management.