postmenopausal osteoporosis
Introduction
Introduction to postmenopausal osteoporosis Postmenopausal osteoporosis (POP) is a common disease associated with aging, mainly in postmenopausal women, due to lack of bone mass and structural changes in bone structure due to estrogen deficiency, making bone fragility more prone to fracture, and Problems such as pain caused by fractures, bone deformation, complication, and even death seriously affect the health and quality of life of the elderly, and even shorten life expectancy, increasing the financial and human burden of the state and family. Osteoporosis associated with menopause is an important health issue that cannot be ignored. In 1993, WHO defined osteoporosis as a systemic reduction in bone mass, accompanied by microstructural changes in bone, resulting in increased bone fragility, and thus a disease with increased risk of fracture. The pathological feature of osteoporosis is bone mineralization. The content and bone matrix components are reduced in proportion, the cortical bone is thinned, the trabecular bone is reduced and thinned, and the trabecular bone is broken during postmenopausal osteoporosis. basic knowledge The proportion of illness: 0.02% Susceptible population: postmenopausal women Mode of infection: non-infectious Complications: fractures chronic low back pain
Cause
Causes of postmenopausal osteoporosis
Effect on calcium regulating hormones (25%):
Estrogen can enhance liver 25-hydroxylase, kidney 1-hydroxylase activity, increase 1,25-dihydroxyvitamin D levels, promote intestinal calcium absorption, and deposit calcium and phosphorus salts in bone, promoting bone Matrix synthesis, estrogen also antagonizes the action of parathyroid hormone, together with parathyroid hormone to maintain the balance of calcium and phosphorus in the blood, parathyroid hormone is a hormone that stimulates osteolysis, when estrogen is reduced, antagonizing parathyroid hormone The effect is weakened, which can accelerate bone ablation and gradually develop into osteoporosis. Calcitonin can inhibit the activity of osteoclasts, and estrogen can promote the secretion of calcitonin.
Participates in bone formation and absorption through the action of cytokines (15%):
Since Komm demonstrated the presence of estrogen receptors in osteoblasts in 1988, Ernst found that exogenous estrogen promotes IGF-I production in rat osteoblasts, which increases estrogen receptors due to increased production of IGF-I. Expression also found that estrogen can promote the production of TGF- in osteoblasts, indicating that these growth factors promote bone formation, and estrogen promotes bone formation through the production of these growth factors.
Experiments have shown that when estrogen is deficient, IL-1 secreted by bone marrow mononuclear cells and IL-6 secreted by stromal cells are increased. Pacifici et al. also found that TNF- and GM-CSF can be produced in cultured peripheral blood mononuclear cells; The levels of TNF- and GM-CSF in patients with ovariectomy are elevated. The levels of TNF- and GM-CSF in estrogen-treated patients return to normal levels. The above cytokines promote the bone resorption process. The production of cytokines inhibits bone resorption.
The direct effect of estrogen on bone cells (8%):
Since 1988, komm has found estrogen receptor (ER) on osteoblasts. In 1990, Penlser discovered estrogen receptors on osteoclasts, which further clarified the direct interaction between estrogen and bone cells. It binds to estrogen receptors on osteoblasts and osteoclasts and directly inhibits lysosomal enzyme activity of osteoclasts, reducing their ability to produce lacunae on bone sections. Shevde was in a castrated rat model in 1996. It is proved that estrogen can directly inhibit the recruitment and differentiation of osteoclast precursor-forming cells (bone marrow hematopoietic stem cells) through the receptor-binding pathway, thereby inhibiting the activity of osteoclasts, and using cell morphology to prove that estrogen is such The effect is achieved by influencing cell cycle-induced apoptosis. In 1997, Kameda applied a highly purified mammalian mature osteoclast, and similar conclusions were reached. Ernst confirmed that estrogen enhances the reproduction of rat primitive skull cells. And intracellular collagen, IGF-I mRNA expression.
First, the cause of the disease
According to the cause, it is divided into primary and secondary osteoporosis.
Type I osteoporosis, also known as postmenopausal osteoporosis, is mainly caused by estrogen deficiency, which occurs in female patients, aged 50 to 70 years, showing rapid loss of bone mass, loss of bone cancellosis, and fractures. In the vertebral body with osteoporosis, the upper end of the femur and the distal end of the humerus.
Type II osteoporosis, also known as senile osteoporosis, compared with type I, male patients increased, but the ratio of male to female is still 1:2, the age of onset is more than 70 years old, manifested as slow loss of bone mass, cancellous bone The rate of loss of bone density is almost the same, and the incidence of hip fracture is increased except for the type I.
In 1983, Riggs compared type I and type II osteoporosis.
Secondary osteoporosis is caused by other causes, such as chronic diseases: chronic renal failure, gastrectomy, intestinal diversion, calcium malabsorption syndrome, multiple myeloma, etc.; endocrine disease: hyperprolactinemia, thyroid Hyperfunction, excessive secretion of adrenal cortex hormones, diabetes, hyperparathyroidism, etc., iatrogenic factors: long-term use of antiepileptic drugs, aluminum antacids, excessive thyroxine or long-term use of glucocorticoids, gonadotropins A hormone releasing (GnRH) agonist or the like is released.
Postmenopausal osteoporosis is a multifactorial disease. Inheritance, lifestyle, and nutrition are all related to the disease. People with high risk factors are susceptible to postmenopausal osteoporosis: white and Asian women, family history of osteoporosis, or Women with special genes affecting bone mass, lack of calcium intake, lack of physical activity, heavy smoking and drinking, early menopause or bilateral ovarian resection before menopause, whether or not osteoporosis occurs, depends on its bone peak and The rate of bone loss, high bone peaks and/or slow bone loss are less likely to occur, and low bone peaks and/or bone loss are prone to occur.
1, bone peak
Bone peak refers to the highest bone mass in a person's lifetime. It is generally reached at 25 to 35 years old. There are many factors affecting bone peak. Among them, genetic factors are the most important, and nutrition and living habits also have some effects.
(1) genetic factors: determine 70% to 80% of bone peaks, for example, black BMD is higher than whites and Asians, the incidence of osteoporotic fracture is low, osteoporosis has a family tendency, BMD difference of single-oval twins Compared with double-oval twins, males have higher bone peaks than females. In some countries, vitamin D receptor gene, estrogen receptor gene, or collagen gene polymorphism is associated with BMD, and the bone peak is inherited. Factor influence.
(2) Nutrition: Those with high calcium intake during adolescence have higher bone peaks and up to 6% of mature bone BMC. The World Health Organization recommends that the elemental calcium intake during adolescence should be 1000 mg per day.
(3) Lifestyle: exercise can increase BMD. If you insist on daily exercise, the physical activity is higher than the average amount of 1SD, the bone volume is 7% to 10% higher than the average activity of 1SD, but excessive exercise When the gonadal function is low and the amenorrhea occurs, the bone mass decreases, and a large amount of smoking occurs before the bone peak is formed. The bone peak of the alcoholic drinker is low.
(4) Primary hypogonadism and delayed puberty development, low bone peak.
2, bone loss rate
Women's bone loss is associated with aging and menopause.
(1) Age-related bone loss: Spinal bone loss generally begins at 40 to 50 years old, the loss rate is 0.8% to 1.2% per year, and the loss of limb bones is about 10 years later, that is, from 50 to 60 years old, the loss rate is It is linear from 0.3% to 0.6% per year, and its mechanism is unclear. It may be related to the reduction of bone formation. The consequence of this bone loss is that the trabecular bone becomes thinner and the perforation of trabecular bone does not occur.
(2) Bone loss associated with menopause: Regardless of age, once menopause, the estrogen in the body drops sharply, the bone loss increases logarithmically, the trabecular bone becomes thinner, thinner, and even broken (perforated), bilateral ovaries After resection, the ovarian-derived sex hormones disappeared and the bone loss rate was faster. At this time, the bone loss was twice that of the limb bones, and the loss rate was as high as 4% to 5% per year. After 5 to 10 years, the bone loss rate was reduced. Slow, bone loss in the limb bones is slow and the duration of loss is also long.
Animal experiments and clinical observations have confirmed that after excretion of estrogen in ovariectomized or postmenopausal women, the bone turnover rate is reduced, which can effectively prevent bone loss. It is also proved that estrogen deficiency is the main cause of postmenopausal osteoporosis. .
Second, the pathogenesis
Normal bones are continuously renewed by bone remodeling. The osteolytic effect of osteoclasts is hollowed out under the bone surface to form bone lacunae, and then a group of osteoblasts migrate to the bone lacuna to synthesize and secrete collagen and bone. The related polypeptide protein is formed, and the calcium matrix is deposited to form a bone matrix. The bone lacuna is repaired by the newly formed bone matrix, and a bone reconstruction unit is completed. The period is about 3 to 4 months, and the bone turnover rate refers to the old bone absorption and The rate of new bone formation process, decreased estrogen after menopause, increased bone turnover, increased bone loss, high conversion osteoporosis, and the effect of estrogen on the pathogenesis of osteoporosis, mainly through the following pathways.
Prevention
Postmenopausal osteoporosis prevention
After menopause, with increasing age, bone density will gradually decrease, and the risk of osteoporosis and the risk of fracture will increase dramatically. The main goal of prevention is to control the risk factors of osteoporosis throughout the life of women.
1. High risk factors for avoiding osteoporosis from youth to old age
These factors include a large number of smoking, alcohol abuse, sedentary lifestyle, anorexia and taking certain drugs (such as corticosteroids, heparin and certain anti-epileptic drugs), should focus on outdoor activities, sunshine, nutrition, moderate weight-bearing exercise and Prevent falls.
2, attention to calcium supplements in youth
This method, combined with regular, moderate exercise, allows women to achieve optimal peak bone mass.
3. Prevent estrogen loss after menopause
The effect of hormone replacement therapy to prevent osteoporosis in the first 5 to 10 years after menopause is positive. However, since hormone replacement therapy has indications and contraindications, it should be used under the supervision of doctors for different individuals. safe.
4. Calcium and vitamin D supplementation in old age
It can partially prevent bone loss and osteoporotic fracture, but if combined with anti-bone resorption drugs (estrogen, calcitonin, bisphosphonate, etc.) will play a significant therapeutic role.
Although some risk factors such as early menopause and family history of osteoporosis cannot be changed, the above interventions can indeed benefit high-risk groups and reduce the incidence of osteoporosis and fractures.
5, to prevent the elderly from falling
It has been reported that about one-third of the elderly aged 65 or older fall down each year, half of them are recurring falls, and about one of the 10 falls causes serious injuries, such as pelvic fractures, fractures in other parts, hard Subcerebral hematoma, severe soft tissue injury and head injury in other areas, the treatment of osteoporotic fractures in the elderly is difficult, such as long-term bed rest, slow blood flow, lung and tracheal secretions are not easy to cardiovascular disease and Pulmonary infection, which will increase the mortality rate of elderly patients, thus preventing the elderly from falling and avoiding the occurrence of fractures, can effectively improve the quality of life of the elderly.
Factors associated with falls include arthritis; depression; static orbital (orthostasis); cognitive function, vision, balance, gait or muscle resistance; use of multiple drugs, etc., associated with increased risk of falling The drugs include serotonin reuptake inhibitors, tricyclic antidepressants, neuroleptics, chlordiazepoxide, anticonvulsants and some antiarrhythmic drugs.
The doctor should know the patient's medical history of falling and find out the risk factors that cause the fall and avoid it. After assessing the risk factors at home, the patient should be given targeted advice. The most recommended measure is to remove the loosening. Carpets, use safer shoes (shoes that fit the foot, low heel, and thin bottom), use a non-slip bath mat, use lighting at night, and add railings to the stairs. Effective measures can reduce the risk of falling down by the elderly by about 20%.
Balance and gait training under the guidance of professionals and exercise to enhance muscle strength, gradually reducing and stopping the use of psychotropic drugs are also associated with a decline in the incidence of falls. For patients with eye disease, syncope, and arrhythmia, they should be transferred to ophthalmology, cardiology. Visit a physician to find out the cause, target treatment, and prevent falls.
Complication
Postmenopausal osteoporosis complications Complications, chronic low back pain
1. Fracture
It is the main complication caused by osteoporosis. If you are bedridden due to fracture, it is easy to cause pneumonia. Cardiovascular diseases often occur in the spine, forearm and hip fracture. The difference between fractures and healthy people is A minor trauma is a fracture.
(1) Spinal fractures: Spine compression fractures can occur when lifting or pushing heavy objects, bending over, slightly falling, or falling on the buttocks when landing, acute and severe waist, back pain, sometimes accompanied by short stature, or There is nerve root compression pain, and if the vertebral compression fracture occurs gradually, chronic low back pain occurs.
(2) Forearm fracture: It is easy to occur when one hand or both hands touch the ground when falling.
(3) hip fracture: a slight slip can occur, usually in older postmenopausal women, after the occurrence of hip fracture, 15% to 30% died in various complications within 1 year, survivors, About half of the lives cannot take care of themselves and are therefore the most serious complication of osteoporosis.
2, due to the loss of elasticity of the thoracic and lumbar protrusions obstruct the blood circulation and functional activities of the heart, lungs and digestive system, so it can be complicated by chest tightness, shortness of breath, cough, bloating, constipation and other symptoms.
Symptom
Postmenopausal Osteoporosis Symptoms Common Symptoms Osteoporosis Stops Humpback Bone Pain Calves Calcium Level Increased Calcitonin
Osteoporosis is a occult disease that often does not have any symptoms before it breaks. Once a hunchback is found, the body becomes short, or bone pain, fractures often occur. Therefore, clinical symptoms cannot be diagnosed. The severity of the pain can be used to determine the therapeutic effect.
1, bone pain
Osteoporotic bone pain is usually caused by microfracture of the trabecular bone. When the body position changes, the muscles and ligaments are pulled, so it can cause sitting pain, stretching pain after flexion, walking pain, turning pain and lying pain. Etc., usually using four-level scoring method to reflect the degree of pain, 0 is divided into painless, 1 is divided into sometimes pain, 2 is often painful, but can be tolerated, 3 is painful, and affects work and life.
2, hunchback or short stature
Appears when a compression fracture occurs in the spine.
3, local tenderness or snoring pain
It is characterized by no local redness and fever.
According to the above clinical manifestations, laboratory tests and auxiliary tests can make a diagnosis in the early stage of osteoporosis.
Examine
Postmenopausal osteoporosis examination
1. Biochemical indicators of bone resorption:
(1) Urinary Ca/Cr: Bone calcium enters the blood circulation during bone resorption, causing blood calcium to rise, and then urinary calcium is elevated, so urinary calcium can reflect bone resorption, calcium content in the diet, intestinal calcium absorption and renal function. The blood and urinary calcium levels are affected, so the specificity is not strong. The urinary calcium after 12 hours of fasting can avoid the influence of food, mainly responding to the bone resorption status. In order to avoid the influence of the previous day's diet, the first urine after 12 hours of fasting is discarded. A second urine test was taken on an empty stomach.
(2) Urine HOP/Cr: 50% of urinary HOP is a metabolite of collagen. When bone resorption increases, the ratio increases. To avoid the influence of diet, in addition to the second urine that needs to be fasted, it should be left. The food containing collagen was fasted for the first 3 days of the urine specimen.
(3) Type I collagen pyridine cross-linking and terminal peptide: metabolites of collagen in bone, cartilage and other connective tissues. When bone resorption increases, the content of blood or urine increases, because the transformation rate of bone tissue is much higher. Cartilage and connective tissue, so the main reaction bone absorption status, its level is not affected by diet, urine Ca / Cr and urine HOP / Cr reflect the specificity of bone resorption, the current determination of urine Pyr / Cr, DPYr / Cr; Blood type I collagen cross-linked amino terminal peptide (NTx) or c-terminal polypeptide (CTx), NTx is a direct product of osteoclast-degrading collagen, and the structure of CTx is shared by type I collagen in all tissues, so Specificity is worse than NTx.
(4) Blood-resistant tartaric acid phosphatase (TRAP): TRAP is synthesized by osteoclasts and directly secreted into the blood, thus reflecting the condition of osteoclasts. When bone resorption increases, blood TRAP increases.
2. Biochemical indicators of bone formation:
(1) Serum alkaline phosphatase (ALP) and bone alkaline phosphatase (bAIP) AIP are produced by liver and osteoblasts. The small intestine source accounts for 25%, the proportion of fasting is reduced, and the source of kidney is rare. Therefore, when the liver function is normal, it reflects the activity of osteoblasts, and bALP is only derived from osteoblasts, so it is highly specific.
(2) Serum osteocalcin (BGP): BGP is the most abundant non-collagen protein in bone tissue. It is produced by fine bone formation. Mature BGP molecules are secreted outside the cell, most of which enter the extracellular bone matrix, and a small part enters the blood circulation. BGP in the blood of postmenopausal women with osteoporosis may be elevated, decreased or normal, depending on the rate of bone formation, increased BGP levels after treatment with bone stimulants, and decreased levels of BGP after bone resorption inhibitors. In patients with dysfunction, blood BGP is elevated (BGF is filtered and degraded by the kidney).
(3) Serum type I collagen propeptide: Type I collagen is synthesized by osteoblasts, and its amino terminal (N-terminal, PINP) and carboxy terminal (C-terminal, PICP) extension peptides can be determined by specific enzyme digestion. It reflects the synthesis of collagen, but skin, teeth, cardiovascular and other tissues that can synthesize type I collagen can also be produced.
3, bone mineral content (BMD) determination: is currently the main basis for the diagnosis of osteoporosis, because bone density can largely predict the risk of fracture, WHO revised the diagnostic criteria for bone mass measurement in 1994 as BMD Or BMD is lower than the average of normal adults for more than 2.5s, called T-Score. The calculation method is (measured BMD - average adult BMD) ÷ standard deviation, but the occurrence of fracture depends not only on In BMD, it is related to bone strength. Bone strength is composed of BMD and bone mass. Therefore, the diagnostic method needs to be improved.
(1) Method for determining BMD:
1X line photo: It is the earliest applied qualitative or semi-quantitative bone mass measurement method. The so-called qualitative method is to observe the density difference between the bone tissue and the soft tissue adjacent to it by the naked eye. The difference is high, the bone density is high, and the difference is small, the bone density is low. In the absence of difference, the bone density is the lowest. In addition, the bone density is high and the bone density is high, and the bone density is low and the bone density is low. The bone density is high, and the bone density is high, and vice versa. When severe osteoporosis occurs, The bone pattern is small and the cortical bone is linear. In 1955, Lachman proposed that 30% to 50% of BMD loss can be found on X-ray photographs, so it cannot be used for early diagnosis. Later, a semi-quantitative method, that is, a small femoral neck, appeared. The beam index method (Singh index) and the calcaneus index method, the femoral neck trabecular index method is divided into I-VII grade according to the distribution of the femoral neck trabecular bone, and those below grade III are definitely osteoporosis. The calcane trabecular index method is divided into 5 degrees according to the trabecular bone density, 5 degrees and 4 degrees are normal, 3 degrees is suspicious, and 1 degree and 2 degrees are osteoporosis.
The current application value of X-ray photographs in osteoporosis is to diagnose whether there is a fracture, whether it is accompanied by bone hyperplasia and bone deformation, and distinguish it from other bone diseases, such as bone tumors, osteomalacia, etc. Therefore, it cannot Discarded.
2 Single-energy photon absorption (SPA): SPA is a bone mass measurement technology developed in the 1960s. The principle is that radioactive nuclides can be absorbed by bone tissue when they pass through the human body, and the unabsorbed part is emitted. The detector on the opposite side of the source receives, and the ray count is automatically processed by the computer to display the bone mineral content (BMC), bone width (BW) and BMD (BMC/BW), BMC is expressed in g/cm, and BW is expressed in cm. BMD is g/cm2. When the bone mass is high, the amount of radiation received by the detector is low, and vice versa.
The radionuclide uses 125 iodine (125I) or 241 (241Am). The half-life of 125I is 60 days. It needs to be replaced regularly. The half-life of 241Am is 433 years. It can be used for a long time. This method is suitable for the determination of limb bones with few muscles. Deep bones, such as vertebrae and femur, forearm bone morphology, uniform thin layer of soft tissue around the bone, and the ratio of bone to soft tissue is high, the measurement is not easily affected by technical factors, so it is mostly used for the determination of forearm bone, its accuracy It is 1% to 2%, the accuracy is 4% to 6%, and the measurement takes 5 to 10 minutes. The amount of radiation is less than 1/SV. Because the price is lower, it is suitable for the census, but the forearm is at the junction of the outer 1/3. There are many cortical bones, and the changes after menopause are small. Although the distal end of the forearm is measured, although there are more cancellous bones, the bone shape is irregular due to the proximity of the joints, and the measured value is not ideal, which is the main disadvantage.
Determination method: soak the forearm in the water tank, or pack a water bladder (so that the absorbed photons are equal to the soft tissue, then the difference in the absorption of radiation is only composed of bone tissue). When the measurement site is selected, the machine automatically moves on the limb. Move the detector and automatically display the measured value.
3 dual-energy photon absorption (DPA): The difference between DPA and SPA is that two sources of different energy sources are applied. After the two energy counts are processed and subtracted, the count of all soft tissues is eliminated, and the rest is bone tissue. The counting, so it can measure deep bones such as the spine and femur, but because of its poor accuracy and accuracy, the inspection time is long, and it was replaced by DXA in the late 1980s.
4 dual-energy X-ray absorptive (DXA): The principle is the same as DPA, but the radioactive source does not use nuclide, but uses X-ray tube to separate the photon beam generated by the X-ray tube into X-ray of two kinds of energy. Therefore, it can eliminate the influence of different thickness of muscle around the bone tissue, measure the BMC and BMD of the bones of the spine, hip and any part of the body, and measure the muscle and fat content. The scanning time with the pencil X-ray beam takes 6 to 15 minutes, with a fan shape. X-ray beam scanning only takes 2 minutes, the accuracy is 1% to 2%, the accuracy is 4% to 8%, and the radiation dose is 1SV. It is currently considered as a reliable method for diagnosing osteoporosis and judging the curative effect.
Determination method: the test subject is lying on the machine. When measuring the vertebrae, it can be measured by the anterior or posterior position. The disadvantage of the anterior-posterior measurement is that the elderly patients are susceptible to bone hyperplasia and aortic sclerosis and false negatives are determined. The value is higher than the actual). When measuring the hip, the femoral neck, Wards triangle and large trochanter are generally measured, so it is necessary to rotate the femur 45° to make the measurement site clear.
5 Single-energy X-ray Absorber (SXA): It has the same use and principle as SPA. The difference is that the radioactive source uses X-ray instead of nuclide. Peking Union Medical College Hospital uses SXA to measure the forearm and DXA to measure lumbar vertebrae, femoral neck, Wards. Compared with the large trochanter, the correlation between the two methods is good.
6Quantitative computed tomography (QCT): It is the only method that can measure BMD in three-dimensional space to obtain true volume BMD. The measured value is g/cm3, which is the only method that can measure the BMD of cortical and cancellous bone respectively. For measuring lumbar spine BMD, the standard phantom is placed on the back of the patient during the measurement, and the patient scans synchronously. The scanning time is 10-20 min, the accuracy is 2% to 5%, the accuracy is 3% to 6%, and the radiation dose is About 100SV, due to the large dose of radiation, it is not appropriate to repeat the inspection multiple times.
The QCT used to measure limbs is pQCT, the accuracy is increased to 0.5% to 1%, and the radiation dose is also greatly reduced. Japanese women use pQCT to measure tibia BMD and DXA to measure the spine, tibia and femoral neck BMD. Correlation, predicting fracture reliability is second to DXA, so whether it can be used for diagnosis is still controversial.
(2) QMD measurement quality control index: Accuracy refers to repeated measurement of a part of the variation, also known as repeat error, or accuracy error, usually expressed by coefficient of variation (CV), the larger the CV, the worse the accuracy, CV calculation The law is:
CV = (standard deviation / BMD mean) × 100%
The clinical significance of accuracy is: when judging the curative effect, if the accuracy is 1%, when the 95% confidence limit is taken, the BMD change is greater than ±2.8%, which is meaningful. Otherwise, the error of the instrument itself cannot be judged to be valid or invalid. % confidence limit, BMD change is clinically significant at ±2%. If the bone loss rate is 3% per year, the instrument with 1% accuracy can measure the change, while the instrument with poor accuracy (ie greater than 1%) measures If it does not come out, design the clinical efficacy to observe the number of cases in the human group. For example, when the accuracy is 1%, it is found that BMD is increased by 0.5%, and 42 people are required (according to the statistical formula).
Accuracy: refers to the error between the measured value and the true value (such as the amount of bone ash), that is, the error of the instrument, provided by the manufacturer, the error is prone to false positive, and the false value is less than the true value.
4, bone ultrasound examination
Using ultrasound to pass bone tissue velocity (SOS in m/s), amplitude attenuation (BUA in dB/MHz) and hardness index (SI) reflect bone structure and bone mass. In theory, ultrasound examination reflects both bone The quantity reflects the bone structure, and has many advantages such as no radiation, low price, easy movement of the machine, etc. Some people compare the ultrasonic examination value with the DXA examination result, and the two have correlation, so it can be used to observe the disease change and treatment effect. However, the results of the ultrasonography are not BMC, so there is no accuracy index compared with the true value. There is no recognized diagnostic standard.
5, bone tissue biopsy
The living bone tissue is sliced, the structure and morphology are observed under the microscope, and the bone morphometric indicators such as the trabecular bone area, the trabecular circumference and the bone-like width are measured, which can be used for differential diagnosis of difficult cases and study of bone metabolism. In comparison with the above methods, the diagnosis is more reliable, but the observation results are subjective, so there is a certain difference between the laboratories among the laboratories. In addition, the bone biopsy is an invasive examination. It should not be carried out universally.
Diagnosis
Diagnostic diagnosis of postmenopausal osteoporosis
Diagnostic criteria
Bone mineral content is the standard for diagnosing osteoporosis. In 1994, WHO redefined the diagnostic criteria for bone mineral density as osteoporosis:
1, normal bone mass
BMD or BMC are within 1 standard deviation of the younger adults.
2, bone loss
BMD or BMC are 1 to 2.5 standard deviations lower than the average for younger adults.
3. Osteoporosis
BMD or BMC are on average 2.5 standard deviations or more lower than younger adults.
4, severe osteoporosis (determined osteoporosis)
Meet the above diagnostic criteria for osteoporosis, accompanied by one or more fragility fractures.
Chinese experts believe that the 2.5 standard deviation of the mean bone loss is not conducive to the early diagnosis and treatment of osteoporosis, and it is more suitable for China's national conditions to lose the two standard deviations as the diagnostic criteria.
Differential diagnosis
1, multiple myeloma
Similar to osteoporosis is bone loss, bone pain and pathological fracture. The difference is that multiple myeloma has a bone destruction area on the X-ray photograph, and the condition is progressively worse. The lesion is more common in the skull and pelvis. A bone marrow puncture test can help confirm the diagnosis.
2, bone metastases
Common in elderly women, patients may be associated with bone pain, bone loss and/or pathological fractures. The main difference from osteoporosis is that the primary tumor may be found, and there is a bone destruction zone on the X-ray photograph.
3, osteomalacia
Because BMD is also reduced in osteomalacia and needs to be differentiated from osteoporosis, osteomalacia often occurs in women of reproductive age, and its incidence is related to prolificacy and malnutrition. There are often hand and foot convulsions, blood calcium and blood phosphorus are reduced. Changes in blood tALP and other changes, bone X-rays showed a villus-like change in the bone boundary, and postmenopausal osteoporosis occurred in postmenopausal women, usually asymptomatic, blood calcium, phosphorus normal, blood tALP increased in the normal range, Bone radiographs have clear bone boundaries, but older women lack outdoor activities, inadequate vitamin D intake, and may also have osteoporosis and osteomalacia.
4, secondary osteoporosis
Osteoporosis caused by various diseases or long-term use of drugs, diseases such as hyperthyroidism, hypothyroidism, hyperparathyroidism, diabetes, Cushing's syndrome, chronic liver disease, kidney disease, severe malnutrition, etc. Drugs such as adrenocortical hormone, thyroid hormone, gonadotropin-releasing hormone analogue (GnRH-), heparin, chemotherapy drugs, etc., can occur at any age, detailed medical history and physical examination, supplemented with the necessary laboratory tests, It can be differentiated from postmenopausal osteoporosis.
