Osteoporosis is a disease that affects the bones and not the joints as in osteoarthritis. It consists in an accelerated loss of bone mass and impaired bone architecture. As a result, bones become fragile, brittle and more easily susceptible to fractures.
The following pictures (image of a bone biopsy, analysed by a microtomograph) show the effects of osteoporosis on the bone matrix.
Fig. 1 : Normal bone tissue.
Fig. 2 : Schematic diagram showing significant osteoporosis. In osteoporosis, there are perforations in the trabeculae and disruption of trabecular bone microarchitecture which constitute bone fragility
Osteoarthritis, in contrast to osteoporosis, is a disease of the joint, i.e. the contact areas between the bones (hips, knees, knuckles, etc.).
To learn more about the formation mechanisms of osteoarthritic lesions, take a look at the section "Understanding."