Lately I’ve been fitting a lot of knee braces. Something about the summer time seems to prompt people to jump off things, ride their bicycles too fast and rollerblade on uneven surfaces. When their stunts go awry, these people come to see me to get fit for a brace.

Knee braces come in all shapes and sizes. Here are some examples:

If the patient is going to have knee surgery (such as to repair some torn ligaments) they will be fit with a brace that looks something like this:

If they need continued support after surgery and rehabilitation they may be assigned a functional brace something along these lines:

If the injury is not bad enough to need surgery but the patient has general soreness and swelling they will probably be given this sort of brace.

I will write a more detailed post another time about the function of each type of knee brace, but right now I want to focus on something that they all have in common. In order for a knee brace to work, it has to stay in the right place. It is really hard to keep a knee brace in the proper position. This is a problem that I never encountered with foot orthotics. You see, foot orthotics stay in place because you stand on top of them. Not so with knee braces. Good old gravity works against even the best brace and tries to pull it down.

In the orthotics world we call the ability of a brace to stay in the right place suspension. This is why knee braces have so many straps.  We are trying to suspend the brace above the ground by anchoring it firmly against the leg.

Gravity is only half the problem however. Most people have conical legs. That is to say, the circumference of their thigh is greater than the circumference of their calf. Think of the shape of an upside-down traffic cone.

conical legs

Now think this through with me – Let’s say your leg is shaped like that. Even if you were to tighten the straps on your brace down really hard, what is to keep the whole thing from sliding south? Not much. In fact, there is only 1 thing that stops the brace from migrating down around your ankles. It is called the Gastrocnemius and is definitely in my top 10 list of the coolest muscles in the body.

gastroc

The Gastrocnemius forms a little “shelf” in the back of the calf where the leg is a little bit skinnier just below the knee. This is the place to win the fight against gravity. In order for a knee brace to be suspended effectively it has to grab onto the leg right here. If you look back at the three types of knee braces at the top of this blog, you can see that each model has a strap in this spot. That is no coincidence.

brace stapping

Many knee brace wearers don’t understand this fact. People often over-tighten the straps of their brace and then they just have a really uncomfortable knee brace that still feels like it is going to fall off. This leads to skin irritation and rubbing and general miserableness that causes people to abandon their braces. Knee braces are only effective if they are actually worn. And worn correctly I might add.

If you are a knee brace wearer, don’t let gravity get the better of you. Harness the power of your Gastrocnemius and keep that brace suspended.

Also, enjoy the last of this warm summer weather and try not to hurt yourself doing anything stupid.

Walk well!

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