I don't know, but I wish it were standard procedure. Most patients (and some doctors) don't realize it, but surgical hardware can corrode/rust within the human body, and it doesn't take all that long. It makes me wonder if that isn't the problem when some folks were fine for a few years and come back with terrible pain with no explanation. Part of the problem is, it's almost impossible to tell without physically examing the hardware, and that means opening up the patient again, which no-one wants to do.
http://neurotalk.psychcentral.com/post893434-34.html
http://www.fixscoliosis.com/question...s-rusting.html
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2219664/
https://www.electrochem.org/dl/inter...u08_p31-34.pdf
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