Pain The most common and main symptom of primary osteoporosis is low back pain, which accounts for 70%-80% of patients with pain. The cause is mainly due to excessive bone turnover and increased bone resorption. The pain spreads along the spine to both sides, intensifies when standing upright and stretching or standing or sitting for a long time, decreases when lying on the back or sitting, is lighter during the day, increases at night and when waking up in the early morning, and increases when bending, coughing, muscle movement or bowel movement. Bone pain generally occurs when 12% or more of bone mass is lost. In old age osteoporosis, the vertebral trabeculae atrophy and decrease in number, the vertebral body compresses and deforms, the spine flexes forward, the lumbar muscles double contraction in order to correct the forward flexion of the spine, muscle fatigue or even spasm, thus producing pain. Shortening of body length and hunchback Shortening of body length and hunchback is one of the important clinical signs that appear after low back pain. Among the bones composed of cancellous and dense bones, cancellous bones are more prone to osteo-sulfuric changes. The front part of the vertebrae of the spine is almost mostly composed of cancellous bone, and this part is the pillar of the body with a large weight, especially the 11th and 12th thoracic vertebrae and the 3rd lumbar vertebrae, which have a greater load and are prone to compression fracture and deformation. 24 vertebrae, each of which is compressed by 1mm in front, can lead to forward flexion of the spine and increased dorsal curvature, resulting in hunchback, and as we grow older, osteoporosis increases and the curvature of hunchback increases. The heavier the degree of hunchback, the more obvious the low back pain. In addition to hunchback, some patients also develop thoracic deformities such as backward convexity of the spine and rooster chest. Fracture This is the most serious complication of degenerative osteoporosis. It not only increases the patient’s pain and financial burden, but also severely limits the patient’s activities and even shortens life expectancy. According to our statistics, the incidence of fracture in elderly people is 6.3%-24.4, especially in elderly women (over 80 years old). Fractures caused by osteoporosis are more common in the early stages of old age with distal radius fractures (Colles fractures), and later in old age with fractures of the lumbar spine and upper end of the femur. Fractures generally occur when 20% or more of bone mass is lost. About 20-50% of patients with vertebral compression fractures have no obvious clinical symptoms. Decreased respiratory function If osteoporotic thoracic and lumbar compression fractures are severe, they can lead to kyphosis of the spine and cause thoracic deformity, which can lead to functional changes of several organs of the body, among which the respiratory system is particularly prominent. The lung capacity and maximum air exchange volume can be significantly reduced, and patients can often experience shortness of breath, chest tightness and dyspnea.