It depends on the horse I have one that can go every six months and one I need to get done every 3-4 months depending how much she is getting ran. I just go off what my horse is telling me, I can tell when she starts to get sore and needs to go to the vet, she will stop firing still clocks well but just does not run as hard and gets body sore. The other will start cross firing and get to swishing her tail around the barrels.
its good to radiograph before the first round of injections and then periodically radiograph them after, maybe once every year or two.. more frequently if you are concerned about them fusing.
We have one that gets done every 6 months, one that gets done every 8 ish months, and one that gets one hock done every 2-3 months and the second hock every 6.
The ones I've injected had X-rays to confirm the need and to rule out stifles. I've had really good luck extending the injections to a year or more by using pentosan monthly. Both of my guys have confirmed arthritic hocks. Pentosans mechanism is to "wash" the arthritis from the joint.
I try to x-ray once every couple of years just to check the arthritis in my good mare's front left pastern, I haven't updated the x-rays on her hocks in several years. She is routinely injected once a year in the pastern and both hocks.
So, in answer to your questions, having a record is good at a minimum of once a year, or every other year. And, don't be like me and put the x-rays off.
Hock Injections
