Yes, I also wondered whether it could be metabolic bone disease, so I mentioned it to our local carer and she pretty much ruled it out. Hedgehogs with MBD are more or less in a total state of collapse and barely able to put one foot in front of the other. She has treated a few hedgehogs with this distressing disease and in an attempt to stop people feeding too many mealworms to their visiting hedgehogs has written a brilliant article which I shall be posting on here shortly.
One of the other hedgehogs with the problem is definately another male, so I don’t think pregnancy can explain it either! My worry is that it could be some kind of chemical in the environment affecting their nervous systems. 🙁
At least it hasn’t affected their appetites, we are being eaten out of house and home at the moment!