I been looking at Kelly’s BASL. He notes a knees forward fault in the air squat. Also noting the shear forces and damage potentially being done to the knee. However in front squats and overhead squats the illustrations clearly show Diane Fu’s knees forward and over the toes. I’m unable to remain upright with arms locked out overhead while keeping my shins vertical. Only when my knees move forward am I able to remain upright and balance in a deep full squat upright position. I’m just swindle ring if this is a fault because it seems like all the lifters who perform front, overhead squats and snatches etc have their knees forward?
You may need to work on hip external rotation, thoracic spine mobility and I know that when my hamstrings get tight it’s hard to maintain a vertical shin during power cleans and deadlift etc. Check these out: