Osteoporosis is characterised by trabecular bone loss resulting from increased osteoclast
activation and unbalanced coupling between resorption and formation, which induces a
thinning of trabeculae and trabecular perfo
rations. Bisphosphonates are the frontline therapy
for osteoporosis, which act by reducing bone remodelling, and are thought to prevent
perforations and maintain microstructure
. However, bisphosphonates may oversuppress
remodelling resulting in accumulation of microcracks. This paper aims to investigate the
effect of bisphosphonate treatment on microstruc
ture and mechanical strength. Assessment of
microdamage within the trabecular bone core was performed using synchrotron X-ray micro-
CT linked to image analysis software. Bone
from bisphosphonate-treated fracture patients
exhibited fewer perforations but more numerous
and larger microcracks than both fracture
and non-fracture controls. Furthermore, bis
phosphonate-treated bone demonstrated reduced
tensile strength and Young’s Modulus. These fi
ndings suggest that bisphosphonate therapy is
effective at reducing perforations but may also
cause microcrack accumulation, leading to a
loss of microstructural integrity and consequently, reduced mechanical strength.