Yep, the surgeon knows... It was one of my concerns from the beginning (not the Fosomax, but my osteoporosis). I was concerned that drilling holes and screws through bones that ha a tendancy already to crack was maybe not such a great idea (I already had two compression fractures in my back- and have broken my wrists and ankles at least 2x year)... He assured me that this was different and would be okay, that the BMP would solidify the area and strengthen it... "no worries!"
And my Rheumatoligist (who perscribes the fosomax) knows about the fusion, as I also take meds called Remicade & methatrexate that destroy my immune system to slow down the Rheumatoid Arthritis (so I had to very carefully schedule surgery & my medication and take huge doses of strong antibiotics) so both doctors had to work together to make sure I didn't develope complications from the surgery/medications.
It just really suprises me that they would keep me on the fosomax if it contridicts w/ the fusion! GRRRR