Do a google search for “ osphos barrel horse world” and it will bring up lots of threads on the subject from several years of discussions. Lots of reading.
I had a bone cyst in tibia above the hock. My vet believes in a series of osphos shots not just one shot. but will not go past 4. we did 6 wks in between. We xrayed every six weeks to make sure we had progress. Now I am rehabbing him back and he is moving better and better all the time! And last time I xrayed he was in the 90% healed. Of course prayer was the main thing!