I. Clinical manifestations
1.Pain
The most common symptom of primary osteoporosis is low back pain, which accounts for 70% to 80% of the patients with pain. Pain spreads along the spine to both sides, decreases when lying down or sitting, increases when posterior extension or prolonged standing and sitting, and increases when bending, coughing and stooling. Bone pain generally occurs when 12% or more of bone mass is lost. In old age osteoporosis, the vertebrae are compressed and deformed, the spine is flexed forward, and the muscles are fatigued or even spasmed, producing pain.
A recent compression fracture of the thoracolumbar spine can also produce acute pain, with strong pressure and percussion pain in the spinal spinous process at the corresponding site. If the corresponding spinal nerve is compressed, radiating pain in the extremities, sensory-motor disorders in both lower extremities, intercostal neuralgia, and retrosternal pain similar to angina pectoris can be produced. If the spinal cord and cauda equina nerve are compressed, the function of bladder and rectum will be affected.
2. Shortening of body length and hunchback
Most of them appear after the pain. The anterior vertebrae of the spine are heavily loaded, especially the 11th and 12th thoracic vertebrae and the 3rd lumbar vertebrae, which are heavily loaded and easily compressed and deformed, causing the spine to tilt forward and forming a hunchback, and with age, osteoporosis increases and the curvature of the hunchback increases.
3.Fracture
It is the most common and serious complication of degenerative osteoporosis.
4.Decreased respiratory function
Compression fractures of thoracic and lumbar vertebrae, backward curvature of the spine and thoracic deformity can significantly reduce lung capacity and maximum air exchange, and patients can often suffer from chest tightness, shortness of breath and dyspnea.
Second, the examination
1.Laboratory examination
(1) Blood calcium, phosphorus and alkaline phosphatase in primary osteoporosis, serum calcium, phosphorus and alkaline phosphatase levels are usually normal, and alkaline phosphatase levels may increase several months after fracture.
(2) Blood parathyroid hormone should be checked for parathyroid function excluding secondary osteoporosis. Blood parathyroid hormone levels may be normal or elevated in primary osteoporosis.
(3) Markers of bone renewal Some of the serological biochemical indicators in patients with osteoporosis can reflect the status of bone transformation (including bone formation and bone resorption). These biochemical measures include: bone-specific alkaline phosphatase (in response to bone formation), anti-tartrate acid phosphatase (in response to bone resorption), osteocalcin (in response to bone formation), type I procollagen peptide (in response to bone formation), urinary pyridinoline and deoxypyridinoline (in response to bone resorption), N-C-terminal cross-linked peptide of type I collagen (in response to bone resorption).
(4) The normal morning urine calcium/creatinine ratio is 0.13±0.01. Excessive urinary calcium excretion increases the ratio, suggesting a possible increase in bone resorption.
2.Auxiliary examination
(1)Bone imaging and bone density
(1) X-ray of the lesion site can detect fractures and other lesions such as osteoarthritis, intervertebral disc disease and anterior displacement of the spine. Bone loss (low bone density) is seen on radiographs with increased bone translucency, reduced bone trabeculae and widening of their gaps, loss of transverse bone trabeculae, and blurring of bone structure, but usually requires more than a 30% decrease in bone volume to be observed. The biconcave deformation of the vertebral body and the collapse of the anterior edge of the vertebral body in a wedge shape, also known as compression fracture, are commonly seen in the 11th and 12th thoracic vertebrae and the 1st and 2nd lumbar vertebrae.
② Bone density testing Bone density testing is a predictor of fracture. The measurement of bone density at any site can be used to assess the overall risk of fracture occurrence; the measurement of bone density at a specific site can predict the risk of local fracture occurrence.
According to the latest treatment guidelines from the National Osteoporosis Foundation, BMD testing is required for the following groups: postmenopausal women over 65 years of age who are at risk for osteoporosis despite preventive measures and should be treated accordingly if osteoporosis is present; postmenopausal women younger than 65 years of age with one or more risk factors; postmenopausal women with fragility postmenopausal women with brittle fractures; women who require treatment based on BMD measurements; women on long-term hormone replacement therapy; men with fractures following minor trauma; people who show bone loss on X-ray and patients with other conditions that can lead to osteoporosis.
WHO recommends grading osteoporosis based on BMD values, specifying that a normal healthy adult BMD value plus or minus one standard deviation (SD) is normal; a decrease (1 to 2.5) SD from normal is considered bone loss; a decrease of 2.5 SD or more is considered osteoporosis; and a decrease of 2.5 SD or more with a fragility fracture is considered severe osteoporosis.
III. Diagnosis
To diagnose postmenopausal and senile osteoporosis, it is first necessary to exclude various other causes of secondary osteoporosis, such as hyperparathyroidism and multiple myeloma, osteochondrosis, renal osteodystrophy, osteogenesis imperfecta in children, metastases, leukemia and lymphoma.
In 1994, WHO recommended a graded diagnosis of osteoporosis based on BMD or BMC (bone mineral content) values: normal as BMD or BMC within 1 standard deviation (SD) of the mean of normal adult BMD; reduced bone mass as BMD or BMC 1 to 2.5 standard deviations lower than the mean of normal adult BMD; osteoporosis as BMD or BMC 2.5 standard deviations lower than the mean of normal adult BMD Severe osteoporosis is defined as a decrease in BMD or BMC of more than 2.5 standard deviations from the mean of normal adult BMD and is accompanied by one or more fragility fractures. BMD or BMC in this diagnostic criterion can be measured in the mesial bone or peripheral bone.