Re: burning numb legs.
I would suggest you find a new spine specialist for an evaluation. This can be either a fellowship-trained orthopedic spine surgeon or a neurosurgeon. Hopefully you requested a copy CD of the MRI at the time of service. If not, you may want to contact the facility where it was done and request a copy. You will want to take this to the new doctor.
Do you have pain when standing and walking? Your most significant "problem" seems to be at L5-S1 where there are two conditions that result in nerve compression. One is the spondylolisthesis, which is when one vertebra slips over the top of the adjacent vertebra. In this case, it is slipping toward the anterior or front side. Grade 1 is the least severe of the four grades, but it means the slippage is from 1-25% and it can create instability in the area above the sacrum. Sometimes when the slippage is active, a spinal nerve can get caught. In addition there is stenosis (narrowing) in both foramina at this level. The foramen is a small opening that allows the spinal nerve to exit the spine as it goes out to innervate a specific area of the body. When something encroaches into the opening (such as a disc herniation, bone spur, etc.) it narrows the diameter of the opening, making the space smaller and putting pressure on the nerve. It is often stenosis that puts pressure on a spinal nerve that causes the radiating pain we feel running down a limb.
The amount of stenosis is rated "severe" which is just about as bad as it can get. Whenever someone has issues in the lower lumbar area, I always like to remind them that if you develop sudden muscle weakness like a foot drop or sudden bowel or bladder issues like incontinence, seek immediate medical attention. These two things are symptoms of cauda equina syndrome...which is caused by compression of the bundle of nerves that occupy the central canal. It is important to get it checked out right away as nerve damage can occur and become permanent if it is CES.
There are a few things mentioned in upper segments but they are not a big deal and not responsible for the pain and burning in your legs.
I would encourage you to establish a relationship with a spine specialist in your new location. That way, if your symptoms should suddenly worsen, you would have a doctor to call so you could be seen fairly promptly. Otherwise you will have to rely on whatever doctor is manning the emergency room. Also, depending on the amount of nerve compression, you may need a decompression surgery to take the pressure off those nerves. With severe stenosis at the L5-S1 level, you need a good spine surgeon to keep tabs on any changes.