It is possible to injure a nerve when you flash your back. When a patient flashes his back, that is, when there is an acute lumbar sprain, the nerves may be injured as a result of simultaneous lumbar spine trauma, muscle spasm, or aggravation of pre-existing lumbar lesions. The specific situations are as follows: 1. Lumbar spine trauma may occur when the patient flashes his waist, and there may be dislocation of the small joints of the lumbar spine, fracture and other traumas. At this time, the relevant nerve roots of the lumbar spine may be pulled or compressed at the same time, resulting in injury. 2. Muscle spasm. When the above lesions occur, the muscles around the lumbar or hip joints may experience muscle spasm, which may lead to compression of the surrounding nerves. At this time, the patient will also have a certain degree of nerve damage. 3. Causing aggravation of existing lumbar lesions. If the patient himself has lumbar related lesions, such as lumbar vertebral body slippage, lumbar intervertebral disc herniation, the above trauma may lead to the aggravation of the lesion, and then nerve damage occurs. It should be noted that although patients with flashed backs may have nerve damage, it is relatively rare. Therefore, there is no need for excessive panic. It is recommended that patients go to an orthopedic clinic in time after a flashed back to see if there is any nerve damage.