I'm not claiming to be an expert, i'm a student physio however, i would agree with the above.

My geography of the US isnt great but im guessing maine is north of new jersey and therefore colder. It's believed the weather can effect joint pain because of the change in atmospheric pressure which very slightly increases the pressure in the joints, which increases pain. If california's warmer then its worth a try.

I would say your Dr was right, osteoarthritis (OA) is when the cartilage wears away and so the pressure on your vertebrae bones would increase because of the loss of the cushioning you should be getting from the cartilage. Due to this increased pressure more bone is grown so you get little bony spurs-these will impinge on the nerves coming out of your spine which travel to you legs i.e. why you get pain/numbness/weakness in your legs. So surgery can remove the spurs there reducing the above symptoms. You cannot reverse the OA, which is why people have hip/knee etc replacements when they get severe OA in these joints. Unfortunately you can't replace the vertebral joints for obvious reasons-it would destroy your spinal cord=paralysis. So i would say your Dr was right, in that surgery could help with the legs symptoms by reducing the bony spurs but it's unlikely to help your back pain as there's no way to renew the deteriorated joints.

Hope thats helpful, again im not an expert but it makes sense. Sorry it wasnt something a bit more optimistic!!