In 2017 I have bulging L5 and sciatica in one leg. I found a physical therapist who has a PHd in back therapy and he told me the McKenzie Method (u can find people who are trained on line) would cure the sciatica and keep the disk manageable. I have been doing these exercises for 5 years - no sciatica and only minor back pain when I strain my back or do lots of bending. Good luck, hope u can find the right p.t. This p.t. is in Eden NC (Chip Miller).
Hi and welcome to the MS community, not sure why your question landed in the MS community and not neurology or Thyroid communities.
Honestly, from what i've been looking up its an unlikely causation of your lower back pain already but considering all your mentioned medical issues.....
"pituitary dwarfism", "osteoarthritis of the spine and nerve damage in arms", foot drop? ("I also trip and fall a lot somehow I don’t get my foot high enough. Ankles hurt a lot but foot doctor doesn’t know what is wrong yet. Have seen him 2 times this year for severe ankle strain. And put in a boot to wear. "), "parathyroid / hypothyroid / hyper parathyroid", "Osteoporosis in neck and lower back osteopenia in hips" etc
...one or more of these medical issues could potentially be the cause of it and because of your complicated medical history there may not be able to pin it down to any specific cause.
Hope that helps a little, sorry couldn't help more........JJ