Wait, but...
There are common questions that arise after reading this article and learning this information for the first time. Let's take a minute to address them.
"Doesn't the hip socket orientation offset the femoral variation?"
This is a great question. The answer is no. The Mckibbin Instability Index demonstrates variation. It's essentially a sum of femoral torsion and acetabular torsion.
"So everyone is going to blame their bones and not work on their mobility"
No. This is one piece of information to be used in the overall picture of someone and how they move. To neglect boney variations would be the same as neglecting height. Height is boney variation. Do you expect a 7' tall person to move the same as a 5' tall person and play sports the same way?
"Is squatting toed forward vs toed out better/worse?"
That would depend on all the factors above. As long as established biomechanical factors to injury are absent from the squat (such as knees collapsing in, lumbar spine flexing, foot/ankle dropping inward) there isn't necessarily a mechanism of injury. If the hip is positioned optimally and the knee tracks over the middle of the foot, there isn't a common mechanism to injury.
With that said, it doesn't mean squatting with your feet turned out 90 degrees is the best way to exercise and strength train and by absolutely no means should this information be used to allow poor biomechanical squats with the toes pointed excessively out and the knees dropping inward.
