As you mentioned, your best bet is to follow through with your appointment at the Mayo Clinic to find out what is going on now in your back. My back issues began at L4-5 too. When you have DDD and fact joint issues, it is possible you have some instability going on. The facet joints can wear down to the point of being just little nubs which not only cause pain but also some movement between vertebrae that isn't supposed to be there.
It is possible that if you have any loose ligaments in the SI joints, your pelvis may have rotated which can throw everything from your toes to your chin, out of alignment. It can create a feeling of one leg being longer than the other.
Watch your posture for a few days. When you sit, are you sitting squarely on both "sit bones" or do you favor one side? Do you cross your legs? If so, do you usually cross one leg over the other on a regular basis? For example, I sit with more weight on my right side. Without thinking about it, when I look, my left leg is always the one that is crossed over that right leg. When I stand in line or at the stove stirring something, more weight is on my right leg. After years and years of doing this, it had an effect on my spine and the soft tissue of my back. I am working on relearning all these postures in an attempt to rebalance the muscles and soft tissue.
I also have ligaments holding the SI joints that are too loose. This allows one side of my pelvis to rotate forward. This causes pain in my piriformis, and "hip" and makes it more painful to walk.
Unfortunately most spine specialists do not consider issues other than the discs, vertebrae, facet joints and nerves. They are less willing to consider how body alignment, laxity in the SI joints, etc. can result in or at least, contribute to major back pain as well.
One thing you might try until you can get in to see your doctor that helped me tremendously before I had surgery and I still do it every day is to lie on the floor on your back with your knees bent, feet flat on floor. Tuck your chin ever so slightly so that the back of your neck is in alignment with the rest of your spine. Arms are at your sides, palms facing the ceiling. Then you just relax. Breathe slowly and deeply from the belly, so that you can see the belly going up and down. And just RELAX. This posture is very good for those with stenosis. It allows the spine to get out from the weight of gravity and allows the discs to "unload."
Before I had surgery I had both stenosis and spondylolisthesis, and this was the one position that brought me relief. When I couldn't walk any further, I would rest in this position for a few minutes, and then I could walk a bit further. I've been known to find an out-of-the-way corner of an airport and lie down for a few minutes. It doesn't provide any long-lasting relief, but it does allow a bit of relief...and if you have anything that is slipping slightly, it helps the spine to realign itself.
Good luck to you. I hope we have a January thaw so you can safely get to Mayo's.....
