Thanks for that, i will have a read. I dont really know much about it. To be honest i'd ruled it out because my mare has always had sensitive/thin soles and had to have silicone in her shoes to protect her soles, her soles bruise so easily if walking on stoney ground. I will read though and perhaps discuss with my farrier.
Sorry to hear your mare is in a bad way but do not despair.Plenty of horses come back from pedal bone rotation. In fact rotation is a bit of a misnomer. It is the hoof that is growing away from the bone not the bone pushing itself downwards. If you can regrow a healthy foot then the pedal bone will be back in the position it needs to be within the hoof capsule. It's growing the healthy hoof that will be the issue. From the way you describe your mare's history I would say she is almost certainly either Cushings or Insulin resistent and has been for a while - the fact she has always had sensitive soles and needed silicon infill screams that her feet have been hurting for a long time. Sensitive soles are caused by the exact same processes as laminitis. In shod horses the symptoms can be masked by shoes holding the sole off the ground and in extra sensitive cases the use of pads. She most likely has been suffering from bouts of low grade laminitis for as long as you've had her. Do not blame yourself though, in any way. Low grade laminitis is extremely common and unfortunately very easily missed in shod horses.
In the abscene of a doing a test for Cushings/IR I would treat as if she were IR. She is probably a horse that cannot eat grass ever. Instead she will have to live off soaked hay and be kept on a 'dry lot', either a sand paddock, hardstanding, concrete yard - whatever you have access to. Despite what some people think depriving horses of grazing on UK fields is not sad for the horse - if I had the choice my horses would never be turned out on a traditional paddock again! Horses simply aren't designed to eat the grasses we have in our fields and horses like yours unfortunately react extremely badly.
I would also get a hair analysis done - she is very likely short of some crucial vit or mineral and supplementing whatever she is deficient in will get her system back into balance, which is crucial for regrowing healthy feet.
It's already been mentioned in this thread but I urge you to read Founder Prevention and Cure the natural way by Jaime Jackson. It's a brilliant book and has saved the lives of many horses. Jaime has helped thousands of horses recover from laminitis, rotation and even horses where the pedal bone has penetrated the sole and a few cases where the hooves have sloughed off altogether. The hoof has an incredible ability to heal itself and regrow, all we have to do is remove the cause of the damage in the first place.
Good luck and please please read that book.