You may never know what caused it. Spinal injuries are tricky...sometimes crate rest and anti inflammatories help. I am sure you vet told you that if she shows any further deterioration in her neurological functions that you should
immediately get her in to a neurologist. Once they start to deteriorate they can quickly end up permanently paralyzed if it is not addressed quickly. Personally, I would probably do a consult now.
I would never do any types of alternative meds for a spinal injury. That is my preference, but if you should choose to go that route I strongly suggest a consult with a board certified neurologist first!
You can find one at:
www.acvim.org
I hope that Buttons shows improvement very soon!