Question: I have a 14 year-old 14-2hh dressage pony mainly tb. We have had him since last July. Around one month ago while my daughter was having a jumping lesson with him he started hyper-extending his left fore leg, only in the trot and perhaps only 3 times that day, as if he had some rubber from my arena stuck in his boot. That week my daughter rode him 4 times and he increasingly did this extending thing with the left leg and by the end of the week was doing it in walk and trot with both front legs. I called my physio who, although could find a few issues with soreness, nothing that would cause this strange behavior. I called a vet out, checked for lameness and he is sound!, Then we lunged him, with side reins and without, no hyper extension. As soon as I got on him he started doing this thing again both in walk and trot and on both reins and with both front legs. Our Vet put the pony on bute and suggested we keep working him. The next day worked him – he was much worse, tried him on just a headcollar and he still did it. I felt it was conditioned behavior as he only did it twice with the headcollar on. But when I was finished he was breathing really heavy, which was not like him, he is very fit worked by myself 4/5 times a week. I called the vet again and he told me to perhaps rest him. That night had to call vet out on emergency as horse not breathing properly. The vet diagnosed mild pneumonia. Put him on antibiotics for two weeks and Ventapulmin. He had a further week off. Vet checked him and declared him fit to start work. He came back into work yesterday and is still doing the hyper-extension thing, only with front left at the moment. I only rode him for around 10/15 min. Today he has been coughing, no mucous. I have no idea what it could be or where to go from here any suggestions would be welcome.