This week we have a guest post brought to you from my boi Benjamin Fergus, a Chiropractor friend of mine, who sent me an incredibly comprehensive video on squat mechanics.
I first met Ben at a DNS course way back in the day, and he was a pretty sharp kid then. Having watched this video, I can see that his knowledge base has only grown.
In this spot, Ben goes over the mechanics of the bodyweight squat, and I think you folks will tremendously appreciate his explanation of what is occurring at the knee.
Once you’ve finished watching the video, check his stuff out at GRIP Approach. You won’t be mistaken.
The Knee’s Position in the Squat
This overview of the ‘Complex Movements of the Knee Complex’ is not intended to tell you the right way to squat, but rather to show what is happening with the anatomy during movement and why. It also will show you how to read/name the movements with observation from the side and front.
Here on earth gravity is king in a squat. We like to keep the line of gravity and center of mass (COM/COG) situated over the midfoot. All variations of the squat can be seen as unique attempts to move our mass closer to the ground while keeping the COM over the midfoot.
There are no rights or wrongs named in this video, just a look at the possibilities of joint motion. What does ‘ knee internal rotation’ mean? We’ll look at that terminology and study what that translates to at the hip, femur, and shin in this biomechanics breakdown.
Mike Cantrell was in my neighborhood to teach Myokinematic Restoration by the folks at PRI.
And I couldn’t resist.
This is the third time I have taken this course, a course I feel I know like the back of my hand, yet Mike gave me several clinical gems that I want to share with y’all.
This post is going to be a quick one. If you want a little more depth, take a look at my previous myokin posts (See James Anderson and Jen Poulin). Or better yet, take a PRI course for cryin’ out loud.
Hip Extension, We Need That Yo.
Sagittal plane is your first piece needed to create triplanar activity. Since this is a lumbopelvic course, we look at getting hip extension as high priority.
If I am unable to extend my hip, here’s what I could try to use to do it:
SI joint compression
Anterior hip laxity
Gastrocnemius and soleus.
We use two tests to see if we have hip extension: adduction drop (modified ober’s test) and extension drop (Thomas test).
The adduction drop will look at your capacity to get into the sagittal and frontal plane, and the extension drop test will look at your anterior hip ligamentous integrity.
A positive extension drop is a good thing if you are in the LAIC pattern. It means you didn’t overstretch your iliofemoral and pubofemoral ligaments. Well done! The reason why this test is not a hip flexor length test has to do with the femur’s position. In the pattern, the femur is positioned in a state of internal orientation secondary to an anteriorly tipped and forwardly rotated pelvis.
Due to this orientation, the femur must be externally rotated during performance of an extension drop test. This would put the psoas on slack. If you still have a positive test, then we know the anterior hip capsule is intact because that’s the only thing holding the hip up.
We spent a good portion of the day learning about gastrocs. In the LAIC pattern, the right gastroc runs the show as a hip extender AND hip external rotator.
The slight inversion action that the gastrocneumius performs helps pick up the transverse plane slack that the right glute max is malpositioned to do so. This is why the right calf is usually larger than the left.
This test’s pinnacle is the 5/5, to which gives us ground to become alternating and reciprocal warriors.
Just because you can hit 5/5 on both sides does not mean you can alternate well.
I was a prime example in class. Mike had me demonstrate my HAdLT in class, to which I easily hit 5’s on both sides.
Despite my quest towards neutrality, I have not been able to keep good thorax and neck positioning. Thanks wisdom teeth.
So Mike checked my right shoulder internal rotation, to which I had about 70 degrees. Way better than the previous 10 or so degrees I started at.
Then Mike had me perform the left HAdLT, which pushed me into my right hip.
Shoulder internal rotation worsened to 30 degrees.
He then pushed me into my left hip with the HAdLT.
Shoulder internal rotation now 90 degrees.
Even though I can crush the lift test, I do not alternate well because I lose position at other areas.
To truly be an alternating and reciprocal warrior, one must be able to perform alternating activities without losing position anywhere in the body.
Why Can’t I Swing my Right Arm?
In many folks with a LAIC/RBC pattern, you will notice that there is minimal right arm swing. You would think that the right arm would be activity secondary to right lateralization and hemisphere dominance. Not necessarily so though.
Arm swing is dependent on trunk rotation. If the trunk can rotate, then the arms can swing.
In the pattern, it becomes very difficult to rotate the trunk to the right, which mean there is no need for right upper extremity extension. So how about instead we just plaster the arm the side? Not a bad idea.
Crazy Good Cues
To close, Mike is a cueing machine. I picked up three new favorites that we’ve been playing around quite a bit in the clinic.
Press heels down on a chair to decrease TFL. Don’t use a ball because the TFL will attempt to adduct the femur via internal rotation. Then slowly add the ball.
Sigh upon exhalation if you have a patient who is rectus-dominant.
Plantarflex the first big toe to feel the left IC adductor in standing.
“Orthopedic symptoms are the result of bad neurology.”
“Good posture compromises respiratory dynamics.”
“Think before you stretch.”
“Stretching is the equivalent of kicking a horse while pulling on the reins.”
“99% of righties have a left thing.”
“Doesn’t matter what the diagnosis is.”
“Give me sagittal or give me death.”
“Most strength deficits are motor control deficits.”
“Total arc depends on what moment in gait you are in.”