Kelly,
As I read your email, many thoughts come to mind, the first of which is that it is difficult to pass judgment on a horse's behavior without actually seeing the horse in action. I have learned through experience that there is generally more to the story than the person relaying the incident sees, and in this case, it is being relayed third-hand. Usually if I am there in person and able to step back and observe, I can find a cause or a reason that the person handling the horse may be unable to see.
That said, there are a few other thoughts that come to mind. I am not a big fan of cross ties and I think they can be highly dangerous, as in the case of your horse. If a horse panics in the cross ties, the chances of him getting in a big wreck and getting seriously hurt are very high. If your horse were pulling back at all, I would not put him in cross ties. You may try tying him to a solid object or hitching rail in a rope halter to see if that would discourage him from pulling, but sometimes a rope halter can make a puller worse because of the additional pressure on his face. There are several Q&As on my website about horses that pull back and also the use of cross ties, so read more about it there.
The other thought that comes to mind is that this is a cold-backed horse. I am not totally clear on whether or not the horse was saddled when this incident occurred, but it sounds like he was. A cold backed horse will sometimes react violently to the saddle, but typically not until it has been put on, the girth tightened and then the horse moves. When he moves, he suddenly feels the constriction and pressure on his back and blows up, often throwing himself on the ground. I have found this to be especially common in TBs. It is possible that she inadvertently got the girth too tight too soon and when the horse reacted and was cross-tied, a full-blown panic set in. This would also be consistent with a reluctance to move forward.
Horses rear either in a refusal to move forward or when forward movement is inhibited. Pain can certainly instigate rearing in a horse; however, it does not really sound like the previous lameness issue is a factor here. It is possible that when he first blew up in the cross ties; he tweaked his back and then was in pain. Hopefully your chiropractor has made a determination on that. There are also several articles on my website about rearing and the causes and solutions.
Going on the assumption that your horse is cold-backed (which is my best guess), all you need to do is make sure he is not tied in any way when you saddle, massage the girth area before tightening and tighten the girth very slowly, walking him between each tightening. Often cold backed horses will crow-hop a little when you first ask them to canter and you need to just work them through that by continuing to move them forward. These measures will alleviate the problems.
I hope your horse is doing better now. Good luck and be careful!
Julie Goodnight, Clinician and Trainer
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