Gringo has a sketchy past. I know little about what happened to him prior to my ownership. I got Gringo from an ex-boarder. She had gotten him from his breeder. He was only three when I got him and already had so many problems.
By the time I got him in October of 2006, he had already been at numerous (think about 5+) barns in just two short years. He had supposedly been "broke" to ride, but we found out soon enough that he either had no training or very bad training (I personally think it was a combination of both).
It took weeks before I could lead him without either being plowed over or stepped on. He had no concept of personal space and was as flighty as a bird. I do know that when his previous owner (PO) attempted to lunge him, he got away from her and got tangled up in a barbed wire fence. He has scars to prove he lost that battle.
Anyways, the training of Gringo progressed very slowly. He would be making good progress but within minutes would back track - miles back. For every one-step forward, it would be four steps back. It took a long time to build his trust in humans... makes me wonder what really happened in all those barns before I got him.
In early January, the BO thought it was time to finally throw that other leg all the way over. Well, needless to say, that did not go so smooth. I ended up with permanent nerve damage on my left side - primarily in my left arm and leg.
By late winter, we knew something was not right with Gringo. He would have okay days, and then he would have outright dangerous days. No rhyme or reason. No expression before he would freak... just one moment he's with it, the next he's trying to kill everyone.
In May, we stopped training. We just weren't making any progress. By then, I'd already had the vet out a couple times but we could never find anything wrong. Well, in early May we thought we had the culprit... an abscess in the left fore. Treated it for a couple weeks with no real improvement.
Therefore, we had the vet back out. This time we took x-rays. Found out he had fractured the coffin bone (extensor process was where the break actually occurred). So, my options were limited. Stall rest, corrective shoeing or surgery. I opted for a mixture...
In August, after having two months off and just chilling out in the pasture, I send Gringo to my significant other's (SO) parents' house. He had the luxury of being on pasture board for 9 months. Him and I finally bonded when he moved there. I was his "human" and he was always so happy to see me. Those 9 months out there did wonders for him. He became a horse again. He also became more trusting.
In March of this year I took Gringo to the specialist (same one Gus saw actually... love Dr. T) to see if there was any improvement in his x-rays from the previous May. Found out from Dr. T that the break was old... not just a year old, but like years old. Great. So, that means that while the PO had Gringo, this "accident" occurred... and she knew about it.
We never did notice it on the PPE back in October when I had gotten Gringo, but then, I didn't do x-rays. Lessons learn. Anyway, Dr. T recommended corrective shoeing. His other options were joint injections, stem cells, IRAP or surgery to remove the fragment. None of those were feasible... so I opted for the cheaper route.
So, now Gringo is sporting lovely shoes with clips, rocker toes and pads with frog support. He's sounder now then he's been in years. I also had his coffin bone injected back in early August of this year. That injection seemed to cause more issues, temporarily. He was very painful for about two weeks. But, he's seems to be getting along better now.
Thankfully, things seem to be resolving. There's no guarantee he'll ever be sane enough to be ridden. He has such a history and so much of it we don't even know. I do know that he's very reactive to pain... for what that's worth.
ETA: This is more for my own benefit, but here's another blogger's post about coffin bone injuries - great source of information! See: http://behindthebit.blogspot.com/2008/09/coffin-bone-fractures-what-to-look-for.html.