Abstract

Although increased awareness of morbidity and costs related to osteoporotic fractures, real progress achieved only through early detection of osteoporosis before any fractures occur. Dual Energy X-ray Absorptiometry (DEXA) is commonly used for diagnosis of osteoporosis by measuring bone mineral density (BMD), but it has its technical and biological limitations. Moreover, DEXA scanning only assesses mineral content in bones, which is only one component of bone strength, BMD cannot define other biological factors which contribute to fracture risk. The biology of bone turnover can be assessed by bone turnover markers (BTMs). They are metabolic indicators released into serum and their quantity reflects the metabolic activity of bones. Markers of bone remodeling predominantly resorption markers have been shown to predict fracture risk independent from BMD. Osteopontin (OPN) is a non-collagenous bone matrix protein marker, it is a key regulator of many metabolic, inflammatory diseases and contributing to osteoporosis pathogenesis. Published studies suggested that, high OPN level may predict the risk of osteoporotic fractures in postmenopausal women (PMW) independent of BMD. The aim of the present review is to integrate the relationship between OPN and BMD in PMW and to discuss the role of OPN as an early diagnostic factor for osteoporosis