The Real Culprit in Knee Pain

knee pain

The knee is a very sturdy joint. It’s a hinge joint and basically has two main functions; it bends and straightens. Most problems in the knee stem from it’s less stable neighbors, the foot and the hip.

The foot is an incredibly complex structure. It has 33 joints, 26 muscles and over 100 muscles. It absorbs shock and produces force with every step we take. At one point in the stride, all of your weight is on just your big toe. It truly is one of the most remarkable structures of the human body. However, it is not without its own share of problems. Some of these problems come from our own creation; shoes.

Shoes are like braces for the feet. The arch is supposed to be a non-weight bearing structure. It is like a suspension bridge from the heel to the forefoot. We have been sold this idea that we need to support the arch with insoles or proper shoe ware. Once you put a support under the arch, it’s able to relax and the musculature of the arch turns off. Just like with any other brace, the muscles become weak with time and can no longer support our body weight. The foot then everts and pronates. The calcaneus (heel bone) gets off angle and looks like this:

ankle eversion pronation

This sets us up with all kinds of issues. The calf muscles are prone to tightness because they are on all day. With a collapsed arch and pronated foot, the length-tension relationship of the calf changes for the worse. This all adds up to a loss of dorsiflexion.

dorsiflexion

If you just want to walk, you can get away with about 15 degrees of dorsiflexion. But if you want to climb stairs or do deep squats, you need about 30 degrees or more. If you go into a deep squat without adequate dorsiflexion, you will either fall backwards or your foot will turn out. When the foot turns out, the shin rotates outward and the knees cave in. This is a problem. Now the space between your femur and tibia narrows on the lateral side of the knee. This compresses the meniscus which can lead to inflammation and early onset arthritis.

Weakness in the hip can compound this situation. The hip abductors and external rotators have a big role in human movement. They position the thigh outward when squatting or stepping. If they are not strong enough to hold this position and you are missing ankle dorsiflexion, the knee bears the brunt of this inadequacy, and knee pain follows.

Of course there are other causes of knee pain, but the slow steady progression of altered joint mechanics is probably the most common cause of knee pain. If you want to resolve knee pain for good, you have to fix the issues that lead to altered knee positioning. This probably means improving ankle dorsiflexion with calf and soleus stretching, and strengthening the hip abductors and external rotators.

If you want to assess your knee positioning, stand on a step, extend one leg out and perform a single leg step down. Watch what happens to your knee. Does it turn out or in? Look at the difference in these two pictures:

The picture on the left is what you want to avoid. The knee is tracking inward which will lead to knee pain. Notice that the foot is also turned out. These two compensations almost always happen together. Also note that the opposite hip is dropped down. This is a great way the develop bursitis of the hip and some IT band pain. The picture on the right is correct. The knee should be tracking over the pinky toe. If you are unable to perform this correctly, the problem is more likely hip weakness. If you can do this with no problem, perform a deep squat with your feet straight and see what happens. Did your feet turn out?

Did your doctor tell you deep squats cause knee pain and can damage your knees? I personally cannot buy into this. The human body is more resilient than that and it is a normal human movement pattern. I spent some time in the philippines and it would be common to see old men resting in a deep squat position, eating their lunch. Look at this guy, I bet he has no pain:

deep squat

It’s all in how you do it. We know the body is a master compensator so if you have restriction in somewhere, your body will find what needs, placing the neighboring joints at risk. If you are able to clean up the restriction and hip weakness, I don’t see why you should avoid this position if it’s body-weight only.