Reece back end giving way.

Hi Karen and welcome!
Unfortunately, that's a problem I think most of us have with our older goldens.
I have a female that's going to be 13 in March and a male that will be 12 in January. My male is having problems with his back end, too.
Is his problem pain or weakness or both? Usually it's both in the older guys, so sometimes anti-inflammatories will help them. Also fish oil seems to help a lot of them, it's also a very strong anti-inflammatory. Perhaps you could talk to your vet about either or both of those.
Is his problem more on slippery floors? Cutting the hair out from between his paw pads on the bottoms of his feet can help that.
And, be sure he's getting enough protein in his diet. Senior dogs need more, not less, than adult dogs and if they don't get enough protein they lose muscle mass quickly.
There are a couple of exercises you can do to help strengthen him a little. The easiest one is to just stand in front of him with a treat or something and have him walk backwards. Work up to having him walk 20 feet or so backwards. It really helps with those muscles.
Good luck, let us know how he's doing, and of course, we love photos!

Welcome to the forum!

I agree with the other posters and highly recommend anti-inflammatories, fish oils, supplementation, exercises, water therapy and acupuncture. I've had experience with 2 dogs having back end problems. With our first boy we consulted an orthopedic specialist about his back end weakness and did a trial run with neurontin. It didn't work for our guy but we were lucky to have access to a veterinary acupuncturist. She helped our boy until he reached the bridge at 13 1/2 years due to cancer.
We started our second Golden with hip/spinal/back end issues with a holistic acupuncture vet about 2 years ago. His improvement is dramatic. She uses a combinationof acupuncture, acupressure, massage, B-12 injections, chiropractic adjustments, laser therapy and herbs/homeopaths. Barkley, at 12 1/2 years is now going upstairs like a dog half his age and we see a definite improvement in his back end issues and in his muscle mass. As an added serendipity, his allergies improved with the acupuncture too. The vet we use said all of her seniors seem to have a spark in their step thanks to the acupuncture sessions. Some of the herbs Barkley takes are targeted for his hips and joints. Judging by the dog they must be working.
There is a new cutting edge treatment here in the states that is helping some dogs with orthopedic and arthritic issues (not sure about true neurological issues affecting the rear end)--stem cell therapy. A company called vet-stem is certifying veterinarians in this procedure. Our regular vet does this and she has seen improvement in several of the dogs. Our acupuncture vet also recommends it. After consultations we decided not to pursue it for Barkley because he is doing so well right now with the acupuncture.
Best of luck in helping your precious senior Reece.