Osteoporosis

**Definition:** Reduction of bone mass without alteration in the composition of bone, leading to fractures. Primary osteoporosis can be of two major types: postmenopausal osteoporosis (OSTEOPOROSIS, POSTMENOPAUSAL) and age-related or senile osteoporosis.

**Tree numbers:** - C05.116.198.579 - C18.452.104.579