Benign compression fractures Signal changes in the vertebral body of benign compression fractures vary with the time of fracture. In osteoporotic compression fractures, for example, the typical presentation on T1WI in the acute stage is the presence of focal low signal shadow near the endplate fracture of the compressed vertebral body, the size of which does not change significantly between the first 2 and 4 months, with normal signal in the contralateral part; on T2WI, the signal of the compressed vertebral body is basically the same as that of the adjacent normal vertebral body, and a linear low signal shadow is visible below the endplate, which is due to the fracture line or On T2WI, the signal of the compressed vertebral body is basically the same as that of the adjacent normal vertebral body, and a linear low-signal shadow is seen below the endplate, which is due to the interposition of fracture lines or bone trabeculae, and the signal of the compressed vertebral body is partially or completely the same as that of the adjacent normal vertebral body on enhancement scan. One morphologic change in the compressed vertebral body that is highly specific for the diagnosis of benign compression fractures is the posterior-superior displacement of the vertebral body protruding posteriorly into the spinal canal, which is essentially 100%, but less common. Vertebral osteoporotic compression fractures usually do not have signs of arch root involvement or epidural mass formation. The signal of the compressed vertebral body in the chronic phase is mostly normal on T1WI and T2WI images, and sometimes restricted low signal is seen, but the rest of the signal is normal. Mild inhomogeneous enhancement is seen on enhancement scans. In addition, osteoporotic compression fractures are sometimes seen on plain films with a fissure-like vacuum sign in the compressed vertebral body due to ischemic necrosis of the bone beneath the endplate, a sign that can indicate a benign lesion, and on MRI: low signal on T1WI; signal on T2WI varies with the time the patient is lying down, and low signal on T2WI scan immediately after the patient lies down. This signal change may be due to the slow inflow of fluid after the patient is lying down, which causes the signal change. Multiple vertebral compression fractures do not indicate benign or malignant lesions. It is not uncommon for both benign and malignant compression fractures to be present in the same patient. Therefore, each vertebral body should be analyzed individually for morphologic and pathologic signal changes when observing multiple vertebral compression fractures. The diagnosis and differential diagnosis should be made on a case-by-case basis. MRI imaging sequences Although common imaging sequences (T1WI and T2WI fast spin echo) are generally able to identify benign and malignant vertebral compression fractures, T2WI (no compression lipid) sequences are of limited use in identifying compression fractures due to acute trauma to the vertebral body versus those due to metastases. In contrast, compression lipid (short inversion recovery and T2WI compression lipid) sequences can enhance the signal contrast between normal bone marrow and diseased tissue and are more helpful in showing diseased tissue. Therefore, the above imaging sequences are generally used as routine. Currently, some new imaging techniques such as dynamic enhancement scanning and diffusion weighting have also emerged for the differentiation of benign and malignant compression fractures of the vertebral body. However, because there are few clinical applications, their effectiveness has yet to be further validated. In addition, these new techniques require high hardware requirements for MRI and are difficult to promote in the short term. Advantages and shortcomings of MRI examination Because MRI is very sensitive to signal changes within the compressed vertebral body, coupled with its multi-axis imaging function and high soft tissue resolution, it can well display not only the morphology and signal changes of the compressed vertebral body, but also the surrounding soft tissue lesions. Therefore, MRI is able to make a definitive diagnosis and differential diagnosis for most cases of benign and malignant compression fractures of the vertebral body. However, MRI has a limited role in the diagnosis of vertebral compression fractures caused by some diseases, such as multiple myeloma, which is not uncommon in clinical practice, and most cases show an obvious malignant process, but most of them show the same performance on MRI as benign osteoporotic compression fractures, and only a few patients show malignant compression fractures. Therefore, this should be noted when identifying cases that are non-traumatic and present with benign compression fractures on MRI. Traumatic vertebral compression fractures can be easily confused with malignant compression fractures because of the diffuse low signal of the vertebral body on T1WI in the acute phase and the mass-like appearance of paravertebral soft tissue injuries (contusions, hematomas). However, a patient’s history of acute trauma and other signs such as disc injury, vertebral fracture fragments and spinal cord contusion can help in differentiation. Determining whether a fracture occurs after trauma Trauma is the main cause of fracture, and the determination of whether a fracture occurs after trauma can be analyzed in terms of both post-injury symptoms and functional impairment. If there is severe pain, local swelling, severe subcutaneous ecchymosis, bruising and deformity, there is a higher possibility of fracture. In terms of functional impairment, when the arm is injured, such as poor grip strength of the hand or even the inability to lift something; the lower limb is injured and cannot stand or walk; the lumbar fracture can only lie flat but cannot sit, all should be considered to have fracture. A simple percussion method can also help to determine fractures. If the upper limb is fractured, tap the injured palm with the other hand, and if the injury is painful, the fracture is likely to be large; if the lower limb is injured, tap the heel with your fist, and the injury is painful, it is most likely to be a fracture. It should be noted that the elderly, due to osteoporosis, are sometimes prone to fracture even when the external force is very small, and the pain nerves of the elderly are not very sensitive, which makes the pain after fracture not too obvious or the symptoms will lag significantly. Therefore, once an elderly person has a fall or an external impact, they should pay attention to determine whether they will fracture in time, and if necessary, they should go to the hospital for examination in time.