الفهرس 
OSTEOPOROSISOnly 14 pages are availabe for public view
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Abstract
OP is one of the most important health problems. It is defined as a systemic skeletal disease characterized by low bone mass and micro-architectural deterioration, with a consequent increase in bone fragility and susceptibility to fractures, especially of the hip, spine and wrist. 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. Risk factors such as age, sex, race, genetic, physical activity, nutrition, alcohol, caffeine and drugs especially corticosteroid affect BMD and produce 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 passes through the following four stages; activation, resorption, reversal, and formation.
Growth factors e.g. IGF-I, TGF-β play a role in the increase of bone formation, while cytokines e.g. IL-1, IL-6 and TNF play an important role in bone resorption.
OP is classified as either primary (postmenopausal or age related) or secondary (related to drug therapy such as corticosteroids, or chronic diseases such as RA).
Periarticular bone loss in RA assessed with quantitative bone mass measures such as DEXA which is the worldwide most accepted measure for assessment of OP. It has been showed that patients with RA lose BMD in the early phase more than late phase of their disease. Also, patients with high disease activity lose more bone density than those with inactive disease. Other modalities used to assess BMD in patients with RA are MRI, Radiogrammetry, QCT and QUS.
Calcitonin, HRT and Bisphosphonate are excellent treatment for OP in RA. Raloxiferne, Fluoride and PTH cause an increase in the axial BMD but not decreasing vertebral fracture.
Recently, monoclonal antibody against αvβ3 receptor and AMG 162 antibody are promising in the treatment of osteoporosis in RA.