Closed injections can be performed for lumbar disc herniation, but they are performed under the guidance of a fluoroscopy machine. Since the lesion of a herniated lumbar disc is in the spinal canal, the disc compresses the nerve root and causes edema of the nerve root. Therefore, a longer needle should be used to perform the closed injection, which must reach the intervertebral foramen, where the nerve root is compressed, so that the swelling of the nerve root can be relieved, the inflammation of the nerve root can be eliminated, and the pain can be relieved. Due to the deep location, accurate fluoroscopy must be performed and closed injections for lumbar disc herniation are recommended to avoid blind penetration. If the injection is performed by experience, it is more likely that spinal cord injury or nerve root injury will occur.