Regarding the surgical pin, that was a plot point on House M.D. a few years ago - the pin would have a serial number on it, which can be used to find out the date it was put into place as well as any additional identifying information about Lois, details about her hospitalization and treatment, and probably her medical history.
On House, they had to surgically remove the pin to retrieve the number in order to identify their patient. A CT scan showed the existance of the pin, and the excuse the doctors used to take it out was that the patient needed an MRI. If Lois needed an MRI, the pin would have to be removed, because Magnetic Resonance Imaging machines (I hope I got that acronym right, haha) are basically big magnets - if you have metal pins/plates in your body, they can't put you in it.
Julie
(Whose medical knowledge mainly comes from watching House and Grey's Anatomy
)
