I have a 5 year old with locking stifle in both back legs, I have been told young horses normally grow out of it once they have built up the muscle. In trot he has started doing a hopping on the front end, feels almost like a canter stride on the right front leg. When it first happened I thought he was lame so I gave him some time off work in hope he would sort himself out- it has now been 3 weeks and its not going away even been trying to ride him through it but nothing changes. I just wondered if it could be the locking stifle causing him to do this motion? Any help and advice would be appreciated before I speak to a vet.