Caused by a mild distention of the tendon sheath where it runs over the hock, or by synovitis of the joint itself. A bit like windgalls (but in the hock obviously!). Usually they are cosmetic only and not worth worrying about.
They can be drained but its not usually worth it as you are sticking a needle in the joint! So if they are not causing trouble its best to leave well alone. If they are caused by synovitis an injection of Hyaluric Acid and/or steroids into the upper hock joint might help bring them down but I bet they would come back.
Hock boots might help - either Back on Track ones or magnetic ones, but they might not!
Hi, I agree with everything Halfstep has said.... however.. if they become large and under pressure - eg, you can't push from inside to outside and are not soft.. and coincide with a change in performance from the horse, it is worth getting it checked out.
Mine had one come up a christmas, didn't seem to be causing any problems so did nothing ... however, about a month ago, got a bit bigger, and suddenly the jumping went from super upwards curve to catastrophe.... couple of vet visits and x rays later, turns out he has a very small chip (not in or near the joint thank god) ... thoroughpin drained , pressure gone - happy ponio again - he was not lame, but reacted on a flexion test when examined - So .. yes, they are normally nothing to worry about... but keep an eye on it.
Well basically have a horse at the yard and he has had them come up on both hocks - the left side is big and as GermanyJo said you can push from side to side !!
Horse isnt lame or worried with them but here is the next thing?
He currently isnt being ridden as the girl is doing her A-Levels so no pressure or anything like that but is still being fed a high protein diet (we thought this may of caused it) but obviously not??