Thank you, mrsD.

It does indeed sounds as though biphosphonates may not be the wonder drugs for osteoporotis (another off-label use) they appeared to be only a couple of years ago. That said, if they still reduce the risk of vertebrae fractures, it might be worth it. I can only allude to what my maternal grandmother went through over the last 15 years of her life: it was pretty terrible stuff as her vertebrae turned into tissue paper.

Last I looked, biphosphonates had only been approved by the FDA to prevent bone uptake into the bloodstream of patients with mutiple meyloma and other metastatic conditions impacting bone tissue. Patients who would otherwise be looking at the prospects of near-term renal failure: not sure what role dialysis can play here, but in any event, it's not pretty. And I suspect that, with an average survival rate now approaching 3.5 years from diagnosis, patients with with full blown multiple myeloma would be willing to accept the risk of a femoral fracture four years hence.

That said, Novaris, the manufacturer of Zometa (Zoledronic acid) the biphosphonate I have been given, recommends 4 mg infused over 15 minutes "every three to four weeks" for cancer patients. http://www.us.zometa.com/hcp/product_info/dosing.jsp And that is significantly higher than than what had apparently been the prevailing practice of dosing osteoporotic patients with 5 mg, once a year. See, e.g., Kenneth W. Lyles, M.D., Cathleen S. Colón-Emeric, M.D. et al., Zoledronic Acid and Clinical Fractures and Mortality after Hip Fracture, NEJM Volume 357:1799-1809, November 1, 2007 FREE FULL TEXT at http://content.nejm.org/cgi/content/full/357/18/1799; Chapurlat RD, Treatment of osteoporosis with annual iv zoledronic acid: effects on hip fracture, Ther Clin Risk Manag. 2009 Apr;5(2):169-75, FREE FULL TEXT at http://www.ncbi.nlm.nih.gov/pmc/arti...6/?tool=pubmed

So it's possible that of the many bone fractures of MM patients, some were wrongly attributed to the disease, as opposed to its treatment, sad to say.

For what its worth, my pain doctor started me with three monthly infusion of 4 mg. each, followed up by no more than 1 booster infusion every 10 - 12 months thereafter. [In a much earlier post, I incorrectly stated the mg./dose and overshot the mark by an order of magnitide. I realized my mistake a few of weeks ago when I read the box the vial came in and then doubled checked with the doctor; I must have misunderstood him years ago.] As I now understand it, this appears, in the first year, to have be higher than the dose typically given to patients with osteoporosis, and comparable thereafter.

Accordingly, the comparative dosages may give no comfort to CRPS patients who already have osteoporosis, what's more interesting is in the case of those who have ever been found to have had bone density issues that were presumed seconday to their CRPS.

Whether CRPS patients without osteoporosis are at risk, may at present be an open question. That said, it shouldn't be too hard to put together a multi-center retrospective longetudinal matched pair study using CRPS patients, all of whom had a 3-phase bone denisity study (or an equivlent test) predating the arbitrary lookback date and in any event before the patient had been exposed to either either biphosphonates or pamidromates, and then matching for things like age, sex, prior bone density, length of illness, smoking, etc. At which point it should be straitforward enough to identify those "matching" characteristic (if not all of them) for which the continued use of biphosphonates is problamatic at best.

Finally, and this is just a total guess, but, at least in a perfect world, at least the retrospective aspect of a population study (it's possible to continue with follow up testing on the same people every few years) should be able to short-cut a lot of IRB red tape, to the extent the testing procedures are deemed sufficiently non-invasive. I can hope, right?

Mike