What are the symptoms of osteoporosis? Osteoporosis is a metabolic bone disease characterized by decreased bone mass, destruction of bone tissue microstructure, increased bone fragility, and susceptibility to fractures. Osteoporosis can be divided into primary and secondary types. Pain is the most common symptom of primary osteoporosis, commonly seen as back pain, with the pain spreading along the spine to both sides. The pain decreases when lying on the back or sitting, and increases when standing upright, bending backwards, or after long periods of sitting or standing. Additionally, osteoporosis can lead to a decrease in height, hunchback, and fractures are the most common and serious complications of osteoporosis.