الفهرس 
Introduction and Aim of workOnly 14 pages are availabe for public view
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Abstract
Osteoporosis is characterized by bone fragility, reduction in bone mass and fractures with . minimal trauma. Rheumatic diseases play an important role in producing secondary OP. There are many risk factors such as genetic, race, age, sex, physical activity, nutrition, alcohole, caffeine and drugs especially corticosteroid influence BMD and cause OP. Because it is a silent disease, early diagnosis is very important especially before occurrence of fractures which are the major cause of morbidity and mortality in OP. Bone remodeling serves to remove effete bone, and it is characterized by coupling of the activities of osteoclasts and osteoblasts at thousands of sites in the human skeleton at all times. It starts by activation, resorption, reversal, and formation. Calcitonin is a potent inhibitor of osteoclastic bone resorption. Other hormones e.g. GH, Vit-D, Eg, Progesterone, Androgen and insulin help bone formation. However, PTH, CS and thyroid hormone cause bone resorption. Growth factors play a role in the increase of bone formation, while IL¬I, IL-6 and TNF play an important role in bone resorption. Bone formation markers especially OC and AP and bone resorption markers especially, I-CTP, Dpy and Pyr are excellent laboratory methods for detecting decreased BMD.