lower legs--numb, weakness, veins bulging, muscle wasting, Please help

My mother is having a problem with her lower legs with numbness (when sitting or laying down), weakness, muscle wasting, and now pain in her left hip and she is getting numerous spider veins in both legs and some are bulging/swollen in the left. If she bends down, she needs to hold to something to stand up. She is also losing muscle in her arms. She and I feel that she will lose her legs in the near future if it continues at this rate.

When the symptoms were mild about a year ago, she had a CT done that showed spinal stenosis, which is narrowing of the holes where the spinal cord moves through. The doctors didn't think this was causing the symptoms at the time, but was rather due to low B12 and low thyroid. Both of those issues have been corrected, but the leg symptoms are progressing rather quickly.

Please help.