Facet joints oriented in the sagittal plane allow for gliding during flexion and load-bearing, while open facet joints provide more mobility for twisting.

“some facet joints since you brought those up earlier are orientated like that in the sagittal plane others are orientated more open as we say so if you look at a gymnast who uh in but by definition me I would never choose to be a gymnast but you can tell look at my facettes they're clothed I don't twist very well however when you Flex forward and pull a load those facet joints just Glide past one another so a gymnast by definition is someone who has a lot of mobility in their spine you will see that their facet joints tend to be open now if I said to you who among your patients gets spond is thesis the broken pars bone that holds the facet joint on basically you are going to say well dancers gymnasts the very people that had the mechanical advantage to twist now when they go into extension their facet joints are like shingles on a roof they bend the bars bone creating stress strain reversals and eventually that bone will uh get a stress fracture or a stress reaction and if they keep going fullblown spond all this thesis”