Here's the issue to me. X-rays are not particularly accurate in predicting lameness but they are good at making it hard to sell a sound horse. The harder work you expect from the horse, the more likely his physical issues will cause soundness issues. It's too bad it's not broke yet. Is he really cheap? It would be a risk because you really need the horse to be in regular work to tell if you have a heartbreaker or not. I have had several horses with hock issues that stayed sound and compensated for the weakness they had. One was a 3' hunter that continues to show into her twenties and the other was a high adult jumper that never limped even though I'm sure all his X-rays looked bad. I've also had horses with clean X-rays that limp if you look at them wrong. The difference is that I can sell the wimp but not the sound horse with bad X-rays.
I'm less forgiving of problems when a horse hasn't been in full work. It's too risky unless you have a back field to retire them in easily if things don't work out.
I've heard a lot of people talk about how their horse had "somethingorother" in its X-Rays but those things were stable and the horse went on to compete at a decent level, etc. When you don't have a workload or previous xrays to compare against, it makes things more difficult...
I am not a veterinarian - just a pro trainer/breeder. I have run into the same problem> Several young horses I bred/raised, out of the same mare, had osteophytes (hooks) in the hocks - not just mild ones, but really big ones. All these horses trained great and were never lame. I couple of potential buyers shyed away from them because the pre-purchasing vets declared that they had "arthritis" in the hocks already, until one of the vets said: "I believe the osteophytes are outside the joint capsules, let me ultrasound them!". The ultrasound revealed synovial fluid between the bone/cartilage and the osteophytes, so the diagnosis was that these "hooks" will never bother the horse. A couple of these horses have been competing in eventing (one has recently placed in her first one *) and two are hunters.
I think a lot of vets are either just not experienced enough or not confident enough in their own abilities to say that a certain finding will likely NOT cause a problem.
I bought an unbroke just turned 3yo with mild arthritic "changes" in his hocks. The very good sporthorse vet that vetted him, as well as my own vet (the top sporthorse vet in our area) had absolutely no issue with it. Worst case, they said, we'd need to maintain them as he got older, or could try IRAP.
The horse is now 7, jumping 1.20m+ and showing regularly, and the only time he's been off behind is when he had a giant abscess that blew out his heel. Not on any kind of maintenance.
A boarder had a horse with hooks when he was 3. He is and was "hitchy". New Bolton predicted he would be sound but may require maintenance as he ages. He's a pleasure horse so it doesn't matter to the owner, he's sound thus far.
I'm not sure exactly what IRAP is, other than an injection (is this the one with platelets?). I have a terrible memory.
But my old semi-retired hunter had IRAP done on his knees in our last year of showing. Can't remember the cost, sorry. I swear it took 15 years off him! He felt absolutely amazing, jumped great, and was sooooo much happier.
I'd definitely IRAP again. Such a huge difference.
As for a young horse with changes in hocks, I don't think I'd take that risk. Agree with others, unless horse is cheap (little money loss) or being just a pet/pleasure buddy, I'd be worried about workload.
Horse may also be great, as long as there's maintenance. How much are you willing to do?
IRAP is a process by which blood is w/drawn from the horse, spun down in a particular manner and injected back into the relevant joint. The serum has both anti inflammatory capabilities and is alleged to have regenerative properties as well. As compared to standard joint injections which are typically steroid based, IRAP is thought to be better and safer because it is not a drug, but the horse's own blood. It is on the expensive side, but probably worth it. I'll know in 6-8 months, as I had my mare done last fall. Read below for more info