Osteoporosis: Focus on Bone Remodeling and Disease Types
Chiara Castellani, Erica De Martino, Paolo Scapato
Abstract
Osteoporosis is a common skeletal disease that leads to increased bone fragility, associated with increased risk of fracture and consequent significant morbidity and mortality, and is a global public health problem. It results from a chronic imbalance in bone remodeling, where bone resorption by osteoclasts exceeds bone formation by osteoblasts. Aging, hormonal changes, comorbidities, and drugs influence the process that leads to osteoporosis. In this review, we delve into the pathogenesis of primary and secondary osteoporosis after a summary of the normal physiology of bone homeostasis. Primary osteoporosis includes postmenopausal osteoporosis, driven largely by estrogen deficiency, and age-related (senile) osteoporosis, associated with reduced bone formation. An insight into male osteoporosis and osteoporosis treatment is also provided. Secondary osteoporosis can derive from underlying conditions, such as endocrine disorders, chronic inflammatory and genetic diseases, or prolonged use of glucocorticoids. Clinically, osteoporosis is often unacknowledged, underlining the importance of early risk assessment and diagnosis. A thorough understanding of the disease, its subtypes, and its underlying pathogenetic mechanisms is essential for early diagnosis and individualized treatment, all targeted to effective fracture prevention.