Had Jack to the vets on thurs, they did all the joint movements and could't find the problem, just gave him 2weeks of anti-inflammatory and said if he's still lame after that, to bring him back for an x-ray.I've been told about a greyhound vet that might be able to find the problem without a pricey x-ray, so I think he's my next option if the tablets don't work(fingers crossed). Jeffers!