Lameness in trot on one rein

[PonyPower1980]

Not sure where to start....! Pony diagnosed with spavin in right hock 12 months ago, steroid injections twice , X-rays show slow fusing, cartrophen injections in June and he's on synequin. Exercised regularly, he's 17 now, no jumping, no trotting on hard or uneven ground .

Was all going well until may, then I noticed a head nod only in trot when working on the bit, this was only on the right rein, same side as the 'hock' as such. Perfectly sound on left rein in trot and works nicely, canters on happily, and physio says he is muscled up well after some deterioration last year prior to hock spavin diagnosis, in fact he looks better than ever. He is now on one bute a day, and the head nod persists. Vet been out and it did appear to be getting better, some days it is there, others it isn't, often a good hours hack at walk frees him up and it's not there, but sometimes it doesn't, I am hoping it is just arthritis and a warming up issues, however I have a suspicion there is a foreleg issue. The hock isn't fully fused, it's about 80% fused, so potentially it's a pain from that, but he wasn't very lame when first diagnosed, just unlevel .
Any thoughts would be good, plus I have a video of him being ridden on said rein if it would help!

 

[lizzi2]

Would suggest getting vet out to have another look. See what vet thinks - but a series of physiotherapy, or bowen therapy or equine sports massage might be useful - have seen work wonders!

 

[PonyPower1980]

Would suggest getting vet out to have another look. See what vet thinks - but a series of physiotherapy, or bowen therapy or equine sports massage might be useful - have seen work wonders!

Thanks, called vets and they are coming out again, however today I rode him and worked him properly just to check I am not being paranoid.. And in trot, working in a outline, on the right rein ( this is the bad hock side ) when I ride on correct diagonal he head nods,as soon as I swop to the wrong diagonal the head nod stops. So tried this on the left rein, and hey pretso the same happens , so my first route will be a local osteopath who is highly recommended, as it appears he has been compensating for the right hock with the front left leg when they move in diagonal pairs, the muscle difference is noticeable and he is very tight in his shoulder, just need to get vet to see this first but feel a little positive that I can switch the head nod off as such with the change in diagonal so hopefully it will be a easy albeit lengthy resolution thanks for your reply, but what is Bowen therapy?