Are you positive that this is Metabolic Bone Disease? MBD usually has more significant signs than a single swollen foot. I wont rule it out of course, however, based on the photo and your telling us its in the foot specifically, it looks more like Edema or Gout.
will if u dont mind would u be able to send me a few linkds regarding Edema and Gout.. becasue maybe we have been going the wrong route on curing this... ive treated it with calium drop and a changing my dusting dates!
Fabos, unfortunately, my favourite link about Gout is on the Chameleon Journals website which has been down for a few months or so now. I did not save the information offline so I can't link it to you. However some other decent sources were cited.
I agree with Brandy, IF the swollen area is not cause by physical trama, then it just spells GOUT to me.