
If you have realised that your leopard gecko is suffering from metabolic bone disease (signs being "rubbery" bones, weak jaw, front leg deformity, loss of appetite) i would reccomend using a product called Nutrobal. It contain calcium and vitamin D3 along with other vitamins and minerals all in quite high doses.
Only use a tiny amount and if your gecko is still eating, sprinkle it on it's food but if your gecko has stopped eating then i reccomend dissolving it in water and giving it via a syringe.
This worked very well for my gecko and if it is just suffering from the early stages results will be seen very quickly. Remember to keep giving calcium with D3 regularly (not all the time as this can be dangerous) so as it doesn't suffer again.