1. Sacralization refers to an abnormal appearance of the penultimate set of vertebra (lumbar) that makes it appear like/ fused with the last set of vertebral bodies (sacral).
2. An intervertebral disc prolapse is described at L4/ L5, which causes mild compression of the exiting nerve.
Hope this is helpful.
Do you think surgery is necessary to fix the prolapsed disc? I have tried physical therapy, chiropractic, bed rests, medications and it has only gotten worse.