What Causes Numbness In The Leg Up To The Foot?

Lumbar x-ray findings: degenerative spurring with narrowing of the L5-S1 disc space; moderate DDD. Thoracic x-ray findings: compression fracture deformity involving what appears to be T5 and loss of vertebral body height 20%; mild diffuse DDD. I ve taken calcium with Vitamin D supplements for most of my adult life. I am female, 55 years old, was involved in a major auto accident at age 23 whereby I suffered a TBI (which resulted in mixed seizure disorder and essential tremor, for which I take several meds); also rear-ended in my 30s (diagnosed with bulging disc over tailbone thereafter), and a head-on crash into cement divider just 2 years ago. Since I ve been taking the supplements for years, why is this happening? Do my seizure meds play a part in this? I also get tingling and/or numbness down my left leg into my foot. What treatment do you recommend?