I'm with Loosie on this one. Nice explanation and lines, Loosie!
I'm disappointed that shoes seem to quickly be the answer in the face of problems. Its the trim under the shoe that is for the shoe, not the horse, with the steel shoe locking it in. It will only perpetuate and worsen the problem.
Padded boots would be better and a trim for the horse (barefoot trim) instead of for the shoe. The boots would support the hoof from below and promote concavity in double time. This encourages the last bone in the hoof to get back up to where it belongs and on a thicker sole. This would replace the height of the shoe as the hoof itself is better developed and safe all by itself. A 4" depth of pea gravel is also a great developer.
As it is, within 6 weeks of these shoes, the pathology will be worse and horse just as sore, if not more when this shoe cycle has ended. You're right back to square one on this problem....probably worse with this shoe job.
A good balanced "barefoot" trim, boots for protection for a little while and lots of movement will give the horse his foot back and make it his own. What he does with it is amazing! You will be walking away from this pathology and a lot of others as well.
I wish it was keratin and not Keratex. I won't put formalin (formaldehyde) on living tissues!