Читать книгу Synopsis of Orthopaedic Trauma Management - Brian H. Mullis - Страница 78

A. Primary

1. Type 1: Postmenopausal—decrease in net bone formation.

a. Due to low estrogen levels (low 17β estradiol results in increased levels of circulating pro-inflammatory cytokines).

b. Bone loss is rapid immediately following menopause and tapers as time goes on (less trabecular architecture to resorb).

2. Type II: Senile—age-related decline in osteoblast function.

a. Usually seen in patients over the age of 70 years.

b. Affects both trabecular and cortical bone.

B. Secondary (Type III)—results from medical illness, medication or lifestyle derangement (see risk factors below):

1. The list is quite inclusive, and the mechanisms by which each condition causes osteoporosis are often multifactorial and overlapping.

2. These diseases and their sequelae either result in an impediment to achievement of peak bone mass during youth or increase the rate of bone loss during the remodeling process.