First I appologize for the novel but its been a long confusing couple of months.
The beginning of Oct. My daughter and I try our this 19 yr AQHA. He rides very nicely and has a great disposition. The next day we go back to try him again in a different setting and in English tack and he is like a different horse (very resistant to bridling, more hyper, and bracing his neck at some turns). We watch him being fed and notice that he is dropping food from his mouth and turning his head as he eats. We decide not to consider him any more. 2 weeks later owner texts that they had horses teeth done and he had a swollen tooth socket. It is healed now and horse is bridling fine. We stop by with only 15 min. Notice one day to check if this is true and he does. Set up a time to try him trail riding 2 days later. He does great for tacking up and down the rode but the ride is cut short due to a tack malfunction. (the only thing I notice is he did step funny a couple of times on the gravel). We have him vetted. Vet is impressed at how healthy he is for a 19 yr. Old. He did go slightly lame on right back hock (1 or 2 out of 5) but during the flexion test he was hard to get to trot off right away (i.e. He took a few walking steps before starting to trot). Vet did not lunge him do to lack of space for lunging. We purchase and he comes to our barn a week later. We give him a few days to settle in then he give a couple of kids a walk around the arena and my daughter rides him for about 30 minutes with a very tiny bit of that being trotting and canter. Again he seems a lot more hyper than our first ride. After a week at the barn my daughter has her first lesson with her trainer and the horse is lame at the trot (head bobbing that gets worse when a heavier person gets on). Call out vet who finds 2 small drainage tracks and some foot soreness. Nerve blocks (ab) for the foot make horse sound. X-rays show some navicular changes so we put wedge shoes on front and give horse bute and week rest. Trainer checks on horse in a week (we are on vacation) and he seems good. We get back after 2 weeks and go to have a lesson and he is lame again. No a bit better because he is only slightly head bobbing on corners. Out comes vet, now horse doesn't block sound with same level of blocks. In fact doesn't block sound when blocked from fetlock down. Vet decides it might be in the hind end instead and flexes both hocks and right hock is reactive. Now diagonisis arthritis in right hock give us clearance to ride and options of supplements or injections. Decide to start with supplements. A week later have chiro out, she notices swelling in his suspensory though she says it feels like it may be old. The next day (friday) the horse is turned out with the other gelding for the first time. Saturday we go to ride and I notice heat and puffyness in right fetlock. I give him 1g bute and we check him for lameness which he is at the trot again. Have barn manager isolate him again. Check him the next day and the heat is gone and the tendon has a hard swelling on it but doesn't seem sore. Watch leg for a few days then call the vet to have him ultrasound it. So vet is out yesterday. Swelling feels like it is DDFT. Vet does nerve blocks first to the suspensory which doesn't help and then to the whole lower leg which also doesn't help. Ultrasound shows fluid and swelling of the inferior check ligament, but since nerve block didn't restore soundness vet thinks the lameness is coming from the hock arthritis. He clears horse for light riding (i.e. 70 lb daughter at a walk) working up slowly over the next 3 to 4 months. When asked about prognosis, he feels that if we can get arthritis under control the horse (now 20) should be sound w/t/c with the possiblities of low jumping in many months.
So here is my questions:
1)Could an acute injury to the front cause the back to get dramatically worse (i.e the horse didn't seem that arthritic 3 months ago)?
2)Is he being overly optimistic regarding the chance of future soundness and the length of time to get there?
3) given that this horse is 20 years old and was only lightly ridden last summer would it be fairer to the horse to consider semi-retirement (i.e. Walking on trails with an occasional trot rather than trying to rehab him back to being able to w/t/c 3 to 5 days a week in the arena)?
Sorry again for the novel but it is so hard to explain without a lot of words.