To the hospital, patients often do not know the purpose of the doctor to prescribe a variety of tests, thus calling many patients misunderstanding, thinking that they spend more money, then, on my personal knowledge of a little, to answer for you. The purpose of X-ray examination is to look at the basic morphology of the vertebrae, such as the presence of scoliosis deformity, the presence of physiological curvature, the presence of fractures, the presence of bone destruction, the presence of osteophytes and osteoporosis, the narrowing of the gap between bone and bone, the presence of bone spurs in the intervertebral foramen, etc. It is a kind of plan view, can not see the structure of the spinal section, can not see clearly the nerve roots spinal cord and other structures in the spinal canal, there are certain limitations, often When a narrowing of the vertebral space is found, it can suggest a herniated disc, and further examination is needed. It can be used as a primary screening tool for lumbar spine diseases, so it is widely used for those patients with mild symptoms and short duration in the outpatient clinic, and is inexpensive, at about 55 yuan for one position, and often 110 yuan for the frontal and lateral positions. CT of the lumbar spine is the same imaging principle as X-rays, but CT makes up for the defect that X-rays cannot observe the cross-section, and can be used to observe the cross-section of the vertebrae and the bony spinal canal, and the extent of the lesion and the compression of the spinal canal can be clearly seen for ossified or calcified soft tissues, such as the herniated disc, the posterior longitudinal ligament, and the ligamentum flavum, so it is the first choice for the diagnosis of lumbar disc herniation and lumbar spinal stenosis. CT can only scan 3 segments at a time, and lumbar disc herniation mostly occurs in lumbar 3-4, lumbar 4-5, and lumbar 5-sacral 1. Therefore, for patients with back pain accompanied by leg pain, one lumbar spine CT is sufficient. The cost is about$306. MRI uses a completely different imaging principle than X-rays, and the resolution of soft tissues is far from CT and X-rays, and is mainly used to observe soft tissues in the spinal canal such as nerves and spinal cord. It is mainly used to observe soft tissues in the spinal canal, such as nerves and spinal cord, and to examine long segments, including 7 segments in the cervical spine (2 tests are required for CT), 12 segments in the thoracic spine (equivalent to 4 CTs), and 5 segments in the lumbar spine, and it can also detect tuberculosis and tumors in the spine. The cost is$585 for one site. Then why do some doctors patients just a back pain to give patients to prescribe nuclear magnetic? First, it does not exclude that he does not know, or lazy for the patient to check, identify, directly prescribed a most expensive; second, there is also a class of patients, when the doctor suspected that his upper lumbar spine (lumbar 1-2-3) has problems, such as occupation, tuberculosis, high disc herniation, do an MRI can see the whole situation of the lumbar spine. However, often when there is such a suspicion, the patient has symptoms that typically distinguish a herniated disc from a lumbar disc. Then why cervical and thoracic spine diseases, doctors do not give patients to save money by prescribing CT and directly prescribed MRI? First, because, as mentioned earlier, there are many cervical and thoracic spine segments, and it is difficult to check all of them with a CT of 306 yuan. Secondly, the cervical spinal canal and the thoracic spinal canal are very thick in the spinal cord (cauda equina in the lower lumbar spine), which is the tissue that the MRI is best at observing. When the spinal cord is compressed by ossified tissues, it can be supplemented with a CT exam before surgery because MRI is not as good as CT at looking at bone. Therefore, it is not better to have an exam that is cheaper than better. Every orthopedic outpatient test should be the result of differential diagnosis by the doctor, who finds the disease that should be most suspected from the patient’s complicated narrative, and then uses the test to confirm and substantiate the diagnosis, instead of telling the patient to spend a lot more useless money without knowing the purpose of the test you are doing. When the patient’s symptoms are not serious and short, an X-ray can solve the problem, but when the patient’s condition is really serious, just do a CT or MRI, and save the money for the patient for the previous X-ray and CT tests.