My 2yr old dog gets stiff legs

Question
Hello, I would like some advice on my 2 year old dog who is an english bull terrier cross. We got her a year ago from a dog rescue home and she was found as a stray so we have no previous history. She is very playful with other dogs, however when she has been playing quite roughly she has really stiff legs later in the evening (which can vary from front to back). This will sometimes happen also when she has been lying down for a period of time. This will sometimes suddenly improve when she has been walking around a little. We have been discouraging her from playing roughly with dogs, and this seems to make it much better. Also she has been reluctant to play sometimes, she seems to understand now when to stop. The vet said this could be due to a number of things such as events in her past, and if it gets really painful she may need a scan? I would like any advice on this, and to make sure that we can prevent this getting any worse. She is too young to be havng these difficulties! Thankyou very much.

Answer
My concerns with a dog getting stiff muscles from back to front would be Lyme's disease. I have no clue if it is even in the UK but that is the type of symptom that goes with it. Lameness upon rising that varies from front to back. But there are others as well.

Events in her past do not say much, so what does he mean by that? Fighting, diseases, inherited problems?
She may well have some spinal issues which a scan will show. If she has a narrowing in the spinal column somewhere she might get very stiff as the conduction of the nerves would not be very good.

So for now maybe get her on a regime of anti-inflammatories and keep an eye on her.
Since I am not a vet I cannot throw out there some inherited things that might be an issue from her breed but you could ask your vet. The fact that she is a cross dilutes that somewhat (which is good) but there might still be some chance.

I would do some blood work to start and look for things that can cause lameness like Lyme's.