@Esrgood4u My dog (1/2 Golden Retreiver, 1/2 Standard Poodle, 80 lbs.) just turned 13 yesterday. This is quite old for a god this size, and he is having the same problem as your dog. His hind legs just don't work very well. On slippery floors, he needs to be helped into the standing position. It is like Bambi on ice.
For the past 4-6 weeks, we have been giving him a combination of low-dose CBD oil and Turmeric pills. We have noticed a marked improvement in his mood and activity. He does not seem like he is in much pain and he is more willing to be active. It took a while to get the CBD dose right. Too little does nothing, too much made him extremely calm and content but lethargic/lazy. His hind legs don't work any better - in fact they are getting progressively worse, but he seems content.
I am not sure how much longer he has in this world, but I am so glad to not have to witness him in constant pain.
Best of luck with your best friend. Is there no way to purchase CBD oil in UK?