Just here for moral support. It’s so hard when your partner is hurting and you can’t find an easy answer, and made even worse when your barnmates are giving you bad advice. Good for you for trusting your gut and getting the help you need. Keep us updated. It does sound like pain, though the other ideas (eyes, lyme, etc.) really could be on to something, as well.
@retiredhorse interesting…sounds a lot like mine. he will willingly jump, but rush or buck out of nowhere at any point in the ride. he was never difficult to handle (past the age of 7) or caused any trouble. I am going to continue to persist! Will mention shoulder, along with back and vision when visiting the vet. thank you so much.
I second the idea for testing for tick borne disease, especially this time of year lyme, ehrlichiosis, anaplasmosis, etc. Another possibility might be metal toxicities? You might look into zinc toxicity or copper deficiency. These can both cause joint pain, change in attitude, difficulty moving/lameness. Did you say you had a blood test? What did it look like?
Update? Reading all this now, another thing to consider is nutritional deficiencies…Selenium? Vitamin E? Especially suspicious is that this started right after you moved. Maybe you moved to a Selenium deficient area? That’s also worth checking out…but it’s two years later…I hope you were able to help him.