chucklefarts 
Contortionist
In the other one she looks like she's a contortionist showing off her muscle control and mid-back flexibility. This one looks like the bend is spread out over more of the spine rather than concentrated dramatically in one spot in the back but the bend is overall less. Arguably, this pose has better form overall when it comes to practicing stretching because of the stretch being spread out over more of the body while the other is more showing off. However, the other pose is good if you're trying to concentrate on stretching that specific part of the back.