Postmenopausal osteoporosis is characterized by an increase in remodelling activity leading to a low bone mass and alterations in microarchitecture, increasing the risk of fracture. Bisphosphonates slowdown remodeling inhibiting bone resorption, thus bone mineral density is preserved with a decrease in the risk of fracture. Such a treatment is often chronic, making the study of their long-term effects on multiscale bone quality (from the crystal to the macrostructure) of clinical relevance. Thank to two different studies on ibandronate and alendronate, we showed that these treatments preserved the mineralization of bone tissue. However, we firstly described that a long-term treatment with alendronate alter the structure of bone mineral crystals with a direct effect on micromechanical properties. Even if, the reduction in the risk of fracture under alendronate has been established after a ten year treatment, our results suggest alterations in bone quality at tissular and sub-tissular levels of organization
