"Knees Bow In" Breakdown

The sign "Knees Bow In" (knee valgus) occurs when the knee caves in during the Overhead Sqauat Assessment. Allowing knee bow in (valgus) during movement may change the stressors of the knee joint, and increase risk of injury. Knee bow in is a combination of hip internal rotation and tibial external rotation, and may indicate overactivity of the tensor fascia latae, biceps femoris, anterior adductors, and potentially the lateral gastrocnemius.

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What do you think most of that comes
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think the biggest joint responsible for this is going to be? Hip, right. Yeah. We've
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got a couple things going on at the hip. This one gets a little complicated. I'm
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going to be honest with you, we'll start with the easy one. Knees moving
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inward is what joint action? Adduction.
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What muscles adduct my hip?
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The adductors. Right? You knew that right? Sometimes we get a "give me" in the
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whole functional anatomy game. You know, it's like, what is the levator scapulae
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do? Uh, elevate the scapula? Sometimes we get "give me"s. Adductors.
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However, here's where things get a little confusing. The other part that's causing
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the knees to buckle in, and this is where it's also related to lower leg
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dysfunction, is what my friend Rick likes to call the bowstring effect. The same
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muscles that pull on the lateral knee, will also duck the knees in. You
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kind of follow me? Here's the easy visual. So if these muscles right here
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pull down this way, like the string on a bow and arrow, if these are on the
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outside and I shorten that string, what's going to happen to the bow? It's
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going to go that way, right? Can you kind of see that? If I drew my knee this
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way, this is my femur, this is my knee, and this is my tibia.
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I drew a little string right here.
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I'm dramatizing. If I shorten this string, what happens to my knee? Can you see
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that? What muscles pull on the outside of my knee? TFL. You're not done yet.
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Short head of the biceps femoris. Why not the long head?
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It's actually a little bit more complicated than that. So what ends up
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happening is it's hip adduction and
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internal rotation.
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This is where things get even more complicated. Femoral internal rotation,
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this is my femur, this is my tibia, this is my knee, if I have femoral internal
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rotation, it is the same thing as tibial external rotation. So all of the muscles
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that we listed for externally rotating the tibia, will also turn the femur
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inward causing this. Are you with me there? So we did TFL, biceps femoris. The
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reason why it's only the short head of the biceps femoris, is the long head of
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the biceps femoris crosses the hip, right? Connects into my ischium.
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What is my the long head of my biceps femoris do as a joint action at
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the hip? It extends the hip and externally rotates. Are you with me
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there? So the long head is actually long, and the short head is short. Darn, crazy
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muscles. Make up your mind! One head's short, one head's long. But it's true.
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So TFL, biceps femoris, possibly even what was the other external rotator of our knee?
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Lateral gastroc, right? We could even, it's not on the next slide,
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but we could even put lateral gastroc.
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Crazy, huh?
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Just gets wilder and wilder. So, if this is the case, adduction internal rotation,
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what would our long muscles be?
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My abductors and external rotators which are going to be, you already hit it,
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who are my big abductor and external rotator? Glute what? Yes. My favorite
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muscles. They are. They're my favorite muscles. Not saying necessarily visually,
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although that's not bad either, but they do have extremely important functions. As
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we start tracking up all of our dysfunctions, you will see the glute
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max and glute med are almost always weak. And then we wonder why so many
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people have droopy glute syndrome. You know droopy glute syndrome, right? No?
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I know a couple of people in here are going, "uhg, droopy glute syndrome". So, what
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would we do to these muscles? Activate, and then we would try to integrate. Okay.
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One thing I need to
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specify: we have to activate, and we have to isolate
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and activate as much as we can. If you go, 'well I need stronger glutes', and you
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decide that you don't do corrective exercise, you decide you're just going to
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do squats to try to strengthen your glutes, is that going to work? Why isn't
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it going to work?
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You're going to continue using the compensation pattern you've always had.
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You with me there? You can't control that. If your glute max and glute medius
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is shut down because your knees duck in, your biceps femoris is going to take
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over, this is something called synergistic dominance.
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I don't care how many times you do squats, your glutes aren't
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all of a sudden on your 15th squat going to go, "oh yeah I'm supposed to work now."
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You've learned to this compensation pattern until you release and stretch
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the short muscles, and activate these guys, they're not going to get involved.