PLEASE HELP!!
My horse is in hospital with a 'mystery problem'.
I bought him a few months ago,he had a 5* vetting and xrays and passed!
(8 weeks ago)I did some dressage on him on a Friday night and he went amazing! I got him out on the saturday morning and he was having a little tantrum! When i got on him he was fine and I just walked round on a loose rein for 10mins, but when I tried to pick my reins up he got really upset!He lifted his head as high as he could to the right hand side and his eyes were rolling..he looked so sore!I only have to touch my reins and he got upset! I got off and thought maybe it was his teeth/sore back?so got dentist out-no probs!and got a physio out, there were some little things but nothing major..i gave him a few days,then tried riding again-no changes!i went abroad for a week and when i came home the 1st time i rode he seemed a little better, i did 10mins of walk, but as soon as i touched the reins he did that thing with his head, got another physio out and she 'fixed him' and still it made no difference.Then i called the vet who came out and wasnt sure what was wrong!now he is in hospital and he has had, xrays-clean, nerve block on face/neck-no difference, ridden with 3 days of bute-went really nicely!so they know somethings sore!,and he had a full body bone scan yest..they are now 'suggesting' kissing spines and are running more tests!!has anyone heard anything like it?!and how serious could it be to him and his carrer?(he is only just 9!)
I've tried everything!!bareback,bridleless(headcoller!),rest, etc..
Any ideas?

Sorry it was such an essay!!