Join Date: Nov 2010
Location: Northern Illinois
It is very hard to tell just from a description. But especially with an OTTB, I would not wait to have a vet come out. He could have sustained an injury from his racing days that is bothering him now. It will do you no good to have a sore horse in training, as it will eventually sour him because of pain. I would personally rule out anything and postpone the training until you are sure he is sound.
Stifle issues can be tricky to deal with, depending on what the issue is. My horse had an issue with his back leg, I thought stifle injury. Turns out it was the hock, he has arthritis and needs injections and he's only 7. Just goes to show you never really do know unless you get a vet out to tell you exactly what is wrong.
** Don't be the rider who gallops all night and never sees the horse that is beneath him **