During one of his usual 'mad puppy charging madly around the house' sessions yesterday, my five month old OES suddenly stopped, looked at his back end and then started to limp quite badly on one of his back legs.  Since then, he has been more subdued and hobbles on it or lifts it off the floor and does the 'three legged' walk.  I have rested him rather than walk him and just given access to the house and garden.  I don't think that there is anything external that has caused this and am assuming that it is a sprain or a ligament injury.  Do you think I am right?  Do you think that I need to just rest him or to take him to the vet?  He is the same this morning, although it has seemed to stiffen up a bit overnight, but it easier since he moved around a bit.  He is a big pup, so I don't want to put his leg under too much strain, or on to the other as he compensates by shifting his weight - they are a breed prone to HD. Any advice would be appreciated please, especially since he is still a baby and really wants to be into everything, so won't rest unless he really has to! Thanks.

If he were mine I would want the vet to look at him, he could have damaged a growth plate or a knee and it is best to let a vet watch how he progresses to see if intervention is required. I am lucky in that my vet is a orthopaedic specialist but still thing to rest and see the vet is the best way to go, unless he is fine this morning.

Just keep an eye on him.  My dog suddenly developed a limp and you know you get carried away..well I thought oh my god he has got it, he has got HD! however my trainer at training school convinced me to calm down and just keep an eye on it.  He limped for about 24 hours then it passed.  I guess he must have given himself a knock whilst playing like a nutter in the park!

Not likely to be HD but pups can do damage to growth plates and a visit to the vet is worth while, better safe than sorry.

I have just had the same problem, my dog has just ran into a wall. I have taken her to the vets they did an x-ray but showed up nothing shes been like it for about a month now and it looks like it could be getting better but we have had her on metacam for the pain.

Ouch, sounds very painful. Hope your dog improves soon Cloe. Thanks to you all for your replies.  Luckily Barney was back on his feet again, quite literally, as the weekend progressed.  Now, he is just getting over a vomiting day by having rice and egg for breakfast - I think he is just going to be one of those dogs!!!!!