We would need to know a lot more about her care to speculate as to why this happened. I would guess that she has suffered a spinal injury of some sort.. perhaps as a result of MBD, but who knows? Your friend should seek the care of a veterinarian ASAP.
my friend is a veterinary,she has made some hypotheses, and she is observing the animal to make a diagnosis, we have written in order to see if someone has experience similar, our fear is that she does not succeed to give birth inasmuch as she would have to give birth soon.excuse for my English.
My experience with hoehnelii is they will drop to the ground when they are spooked,so a spinal cord injury could be the problem.Bottom line however is get her to a vet immediately.Good luck with her.