Patellofemoral Syndrome (PFS)

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In this weeks installment of our “injury of the week” series we’re going to be talking about patellofemoral syndrome or PFS. We’re going to keep the same format we’ve had all along. First we’re going to start off with a review of what the injury is and talk about if this is what you have have and when you need to worry/consult your doctor. From there we’re going to take you through the steps of the A-T-A self treatment system.

What is PFS?? (aka Runners Knee)
This would refer to pain that is around the knee cap (usually on the inside just below it and on the outside just above it). In addition to pain, other symptoms include swelling, clicking, popping and creaking. PFS comes on gradually over time and is worse after rest (sitting for long periods of time and then standing up for example). During activity, symptoms typically start out as an ache/tightness and worsen as exercise continues. Another classic example is pain/creaking/clicking going up and down stairs.

Traditionally, there are two main types of PFS:

1) Symptoms due to abnormalities in the bone. This would include different shapes in the knee cap itself or the groove that it rests in on the femur (long thigh bone). Due to the differences in bony surfaces, inflammation and breakdown of the bone can occur.

2) Symptoms due to muscular restrictions and imbalances. This would include symptoms caused by tight muscles pulling the knee cap out of its normal groove. It also includes symptoms caused by tight muscles pulling the knee cap down tight over the bone so that it grinds or catches, causing inflammation and over time breakdown of the bone.

For this blog post, we’ll be focusing on PFS that is the result of muscular restrictions and imbalances. Proper diagnosis and detection of bony abnormalities is best left to evaluation by your health care team. That being said, if you are experiencing knee pain in conjunction with buckling, locking and painful clicking, it is strongly recommended that you schedule an appointment with your orthopedic for a full workup.

Why does Runners Knee occur??

During normal walking and running, your leg must accept the weight of your body during initial contact with the ground. This impact is absorbed and then transmitted up the leg as you move your body weight fully onto the leg (also known as mid-stance). This momentum is then used to propel the body forward during heel and toe off so that your other leg (which has been swinging forward) can repeat the process all over again as it comes into contact with the ground.

Sound confusing?? Here’s a different way to look at it and the muscles that are involved:

Phase 1) Shock absorption as the foot lands and the leg then straightens to support the full weight of the body = Quads

Phase 2) Moving the body forward over the weight bearing leg = Hamstrings + Glutes

Phase 3) Final push-off = Calf + Big Toe

If there are any hitches or restrictions in the muscles that provide this sequence, other muscles must compensate to maintain forward motion. Essentially, this is what causes “runners knee”. If forward propulsion is interrupted or shortened either at the ankle or knee, the result is a shortened stride that uses the hamstrings and adductors to pull through (instead of the larger glute muscles that are supposed to do the job) and the quads for everything else. With this increased load on the quads (now they have to shock absorb and push off), it is very common for the increased strain on the muscle to affect the knee cap, causing pain and irritation as it gets pulled from it’s normal bony groove.

Here’s a visual of what I mean:

The picture above represents the final phase of push off. The hip is fully extended, the knee is straight, the ankle is pointing down and the big toe is extended. From this point, the ankle fully points down as the calf engages, the knee bends, and the leg can begin it’s swing (typically the force of push off causes the knee to bend enough that the heel comes up towards your butt….this is a major difference between elite level and beginning runners).

To get into this position requires three things:

1) The mobility to straighten your knee all the way. That means flexible hamstrings and inner adductors.

This is what normal knee extension looks like. If you can’t get there, you can’t fully contract your quad muscles, which means they don’t ever fully relax. No relaxing means increased load on the tendon and muscles above it. Remember our saying: if you can’t move it, you can’t use it. This is key if you are plagued by knee pain.

2) Good mobility in your ankle and hip. Unfortunately the knee is stuck in the middle and it can get pretty beat up through no fault of it’s own. This means that you need to be able to extend your hip all the way.

It also means that you can fully dorsiflex your ankle.

Lastly, it means that you’re big toe moves all the way. To truly get the most power from push off, full toe extension is required. If unable to bend your big toe back all of the way, heel off will be limited and the stride shortened. This is often the case with arthritis and bunions.

So what do you really need to take away from all of that??

PFS (the functional kind versus the mechanical kind!) is an injury that happens because of 1) mobility restrictions and 2) strength. You need to fix both components to get rid of it and keep it away for good.

Differential Diagnosis (How do I know if it’s PFS or something else entirely???)

One of the main reasons that PFS (especially when the cause is muscular versus bony) is challenging to treat is because there are multiple things pain around the knee cap might be (these are also known as differential diagnoses).

This picture is where typical PFS symptoms are. Inside the knee cap and outside/above it.

To help differentiate, here are some other possible things that could be going on with your knee.

#1 Quadriceps Tendonitis- This refers to the area directly above the knee cap where the quad muscles become tendon at the top of the knee cap. Very common for this area to get injured due to acute trauma and also due to repetitive overuse. With this injury, pain is directly on the tendon and the tendon itself may be tender or swollen.

#2 Patellar Tendonitis- As the common quad tendon crosses the knee joint, the knee cap actually sits inside of it. The tendon that then connects the knee cap to the lower leg bone (the tibia) is called the patellar tendon. Like the quad tendon, it is a very common area to get injured due to acute trauma and also due to repetitive overuse. With this injury the pain is directly on the tendon and the tendon itself may be tender or swollen.

#3 ITB (Iliotibial Band or IT band)-

One of the easiest ways to differentiate PFS from ITB is to look at where it is. The ITB runs down the outside of the knee and inserts onto the fibular head (little lower leg bone on the outside of the leg). If your symptoms are at the level of the knee cap but are behind it looking from the side, it is more likely that your problem is ITB related versus PFS.

My knee hurts. Now what?

First things first. Like we’ve said all along. This site is not designed to keep you from your doctor and healthcare team. It’s designed to teach you the things that you can do at home to help alleviate symptoms and prevent them from becoming a full blown injury. That being said, if you have any of the following, time to see your doctor. Visible swelling. Bruising around the knee cap. Buckling/giving out of the knee. Numbness/tingling anywhere in the leg. If you aren’t making any progress? See your doctor.

Be smart when self treating at home. If you aren’t getting better, get some help. I can’t tell you how many patients I get who wait weeks and even months before coming in for treatment. The longer you wait, the harder it is to get rid of. Here are some tips for finding the right health care professional:

  • Find someone certified in soft tissue mobilization, whether it’s instrument assisted like Graston Technique or hands on like Active Release (ART). This is where you need to do your homework to see who’s near you. Follow the links to those sites to search their provider lists and read up on what each is all about. Typically with this kind of injury, the whole leg will benefit from getting dug out.
  • Not every PT and chiropractor are created equally. Some do very little soft tissue work and rely mostly on exercise and manipulations, others do not. We all specialize in our own little areas. Frustrating right? Nope! Most of us have websites to tell you what we are certified in. If we don’t? Pick up the phone and call us. There’s nothing worse than wasting 8 insurance visits not getting better only to switch places and have them fix it in two.

How to treat it.

**download PDF with links, sets, reps, progressions, etc here**

Step 1- Traditional R.I.C.E. treatment:

When a new injury occurs, the first and most important goal is always to decrease pain and any swelling that may be present. In other words, we want to decrease inflammation. That means ice is mandatory. Absolutely no heat no matter how good it feels. Don’t short cut this stuff. It’s boring but it works, especially if your symptoms worsen as the day goes. It’s now easier than ever to smuggle an ice pack into the office fridge and wear compression gear under your dress clothes. Use that to your advantage when working to heal an injury!

Rest: This may sound obvious, but I’m going to say it anyway. An injured muscle/joint will require a decreased activity level to fully heal. The severity of the injury will determine if this is a full rest or more of an active recovery.

Ice: while heat may feel better on stiff and sore muscles, ice only during the first 7 days following injury. This will help to decrease swelling, inflammation and pain. 10-15 minutes is sufficient and you can perform every hour as needed. Avoid direct ice to skin contact.

Compression: thanks to the recent explosion of compression sleeves, tights, shorts, etc, you have several options in this department. Ideally you want something that is snug without being uncomfortably tight (think recovery tights if you’ve ever worn them). You can also use a store brought ace wrap to accomplish this. Start the wrap below the injury using good tension on the bandage and move up above the injury. This will help keep swelling from moving down the leg.

Elevation: This is critical in the early days following acute injury where swelling may be present. In the case of an ankle injury for example, elevate the leg so that it is above chest level. This can be accomplished by laying down and propping for your foot up on the arm of the couch with pillows.

Step 2- Kinesiology taping:

For PFS, there are two tape applications to test out.  Both essentially scoop up the lower part of the patella to help it move through it’s normal path. Try both. One may feel better than the other.


1) U-Strip- Click here (you want the first video in this link! )

2) Chondromalacia tape application. Click here.

Step 3- Getting mobility back:

The second goal is going to be to loosen up the injured area. Below I have the treatment techniques set up in levels. As a rule, you must be able to complete #1 without pain to progress to the next level. Be smart! Healing a muscle sprain/strain isn’t about no pain, no gain. The muscle needs to heal! Don’t overdo it in an attempt to speed up your recovery.

1) R.I.C.E. + gentle stretching. There should be no pain with stretching. .

2) Begin using the foam roller AROUND the injured area. The goal here is to start getting slack into the muscle without aggravating the injury itself. No tennis ball work or mobilizations. The order should be foam roll around injury -> stretch -> RICE.

3) Begin using the foam roller over the injured area to tolerance. The order should be foam roll around injury-> over injury -> stretch -> RICE.

4) Begin using the tennis ball for mobilizations. The order should be foam roll around injury -> over injury -> active/joint mobilizations -> stretch -> RICE.

5) Begin using the tennis ball for cross friction + trigger point. These are the deepest of the soft tissue techniques so you want to save them for last to target specific adhesions and restrictions. Consider this your fine tuning step.

How long do you need to R.I.C.E for??? Until it’s 100% gone.

Here’s what it looks like for the PFS. Use the guidelines above.

Step 4: Strengthening

We’ve broken the exercises down into three levels based on pain levels. This stuff should NOT hurt. If it does, go back a level or ease up on the resistance. Only progress as pain free.

What you’ll need: 1) ankle weights or 2) resistance band/tubing. Both are easy to find in any sporting good store these days or walmart/target.

Optional equipment: 1) a balance disc. Always good to add difficulty to your strength exercises. Affordable too at $20. 2) Suspension trainer. I’m a big believer in these because it takes up zero space in my house and is an easy/inexpensive way to add a dynamic component to my strength training. Prices range anywhere from $30-200. Click here to see some of the options out there.

Video’s for each level are here. Please note, in the PDF download (above) you will find details for reps and difficulty progression, as well as, benchmarks you should meet before progressing to the next level. The number one thing to remember is that these exercises should be pain free. If you’re getting discomfort, go back a level. You can’t force this injury to heal, but you certainly can make it worse if you over do it.

Level One


Level Two

Level Three

Hope that helps, and fire away with any questions in the comments section!



1) Capobianco, Dr. Steven and van den Dries, Greg. (2009). Power Taping, 2nd Edition, Rock Tape Inc, Los Gatos, CA.

2) Hammer, Warren. (2007). Functional Soft-Tissue Examination and Treatment by Manual Methods, 3rd edition. Jones and Bartlett Publishers, Inc, Sudbury, MA.

3) Hyde, Thomas and Gengenbach, Marianne. (2007). Conservative Management of Sports Injuries, 2nd edition. Jones and Bartlett Publishers, Inc, Sudbury, MA.

4) Kase, Kenzo, Wallis, Jim, and Kase, Tsuyoshi. (2003). Clinical Therapeutic Applications of the Kinesio Taping Method.

5) Michaud, Thomas C. (2011). Human Locomotion. Newton Biomechanics, Newton, MA.

6) Muscolino, Joseph. (2009). The Muscle and Bone Palpation Manual. Mosby, Inc, St. Louis, MO.

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