No evidence for alteration in early secondary mineralization by either alendronate, teriparatide or combination of both in transiliac bone biopsy samples from postmenopausal osteoporotic patients

The influence of treatment with alendronate (ALN), teriparatide (TPTD) or concurrent treatment with both on the human bone matrix mineralization has not yet been fully elucidated. For this purpose we analyzed quadruple fluorochrome labelled transiliac bone biopsy samples (n = 66) from postmenopausal osteoporotic women with prior and ongoing ALN (ALN-Rx arm) or without ALN (Rx-Naïve arm) after 7 months treatment with cyclic or daily TPTD or without TPTD using quantitative backscattered electron imaging and confocal scanning laser microscopy. Additionally to the bone mineralization density distribution (BMDD) of entire cancellous and cortical compartments, we measured the mineralization kinetics, i.e. the calcium concentration between the younger (Ca_DL2) and older double labels (Ca_DL1), and in interstitial bone (Ca_int) in a subset of the biopsy cohort.