Patellofemoral Syndrome (Runners Knee/Anterior Knee Pain)

Backstory:

I had the pleasure of attending the 2017 Patellofemoral Pain Symposium in Queensland, Australia last year and I would like to shed some light onto this topic today.

The International Patellofemoral Research Network (iPFRN) is a group of researchers and clinicians with a specific interest in Patellofemoral pain across the lifespan.The iPFRN was established by five global leaders in Patellofemoral pain research.

Every two years the group of global leaders come together and discuss all the relevant research available and come up with a consensus statement (Recommendations based on all evidence). I am going to break this down and include my own thoughts and discuss some exciting areas to watch out for (Next blog). There is new evidence out everyday regarding this condition so I will focus my efforts on the 2018 Consensus Statement on Patellofemoral Pain.

So What is Patellofemoral Pain (PFP)?

PFP is a prevalent condition affecting 23-29% of the general population. It is described as pain around or behind the knee, especially during certain loading activities such as running, cycling, squatting or even going up and/or down stairs. Chances are you have felt or know someone who has PFP.

Developing the consensus statement 

The recommendations are based on a literature search yielding 655 papers including 311 systematic reviews and 344 randomized control trials! (Talk about high level of evidence!) Therefore, I am extremely confident in the recommendations from the expert panel.

Recommendations from the expert panel

1. Exercise therapy is recommended to reduce pain in the short, medium and long terms, and improve function in the medium and long term.

2. Combining hip and knee exercises is recommended to reduce pain and improve function in the short, medium and long term, and this combination should be used in preference to knee exercises alone.

3. Combined interventions are recommended to reduce pain in adults with PFP in the short and medium terms. Combined interventions incorporate exercise therapy as well as one of the following: foot orthoses, patellar taping or manual therapy.

4. Foot orthoses are recommended to reduce pain in the short term.

5. Patellofemoral, knee and lumbar mobilisations are not recommended in isolation.

6. Electrophysical agents are not recommended.

So what should i do & NOT DO?

Based on the overwhelming evidence, there really is one answer to help reduce pain and improve function in the long term. You guessed it... It's EXERCISE! Now some of you might be thinking, "If I have pain whilst exercising why would I exercise?" The answer to that would be finding the right exercises to do. I am not telling you to go out for a 10km run, run up stairs, or jump straight into your exercise class! What we do know is using ultrasound and tingly machines are not effective. 

Great, so I need to exercise but which exercise is the best?

Unfortunately, there is no consensus on the BEST exercise prescription (i.e What exercises do you do? How many repetitions? How intense? How often?). These are all fair questions but there is no recipe because everyone is different! However, in saying that, we do know that by adding hip and knee exercises together, we tend to get better results! Now there is a whole list of exercises you can do - I'll list a few of my favourites and the reasons behind them. (Videos will be uploaded soon!)

1) Modified Squat +/- a resistance band
2) Deadlift

Let me illustrate why I like these exercises with this picture. We need to think back to our high school physics. Newton's Third Law states that for every action, there is an equal and opposite reaction. As we bend our knees forward (when we squat) we are creating a moment force that needs to be counter-acted which is the job of our quadriceps. If we go back to our anatomy, we know that the quadriceps tendon is attached to the patella and if we are contracting our quadriceps, we are essentially pulling on the patella causing an increase in compressive forces underneath the kneecap. Since the joint may already be irritated, you may further irritate the joint. That is why I HATE using the leg extension machine for PFP! (Unlike why I LOVE the leg extension machine in Post ACL-Reconstructions).

The modified squat basically limits how far your knee travels forward and the use of the resistance band around the thighs will engage your glutes more! In a deadlift, we are barely moving the position of our knee as it is a hip hinge motion. This allows you to build strength in your hips and knees without aggravating your knees! Now, I'm not saying you should avoid bringing your knees forward in a squat position forever. I actually have no problems with you bringing your knees forward in a squat or in your activities of daily living (as often described as a "bad squat") when you are ASYMPTOMATIC. I will discuss about this misconception health professionals have on "improper squat form" in another blog.

Photo Credit: https://fitnesstogether.com/avon/blog/why-partial-squats-are-a-bad-idea

Summary

Don't worry about all the short term things (foot orthoses, patella taping and manual therapy) that may or may not affect this condition.

What we know is:

1. You need to modify any activities that may be aggravating your condition. 

2. You need to choose an exercise that won't aggravate your knee, and an exercise that will strengthen both your hip and knee!

In the next blog I will discuss the new emerging evidence coming out with regards to PFP (especially relevant to our runners including changing our Cadence? Foot Strike? Education on Load Management? Barefoot running?)