Acute simple traumatic low back and leg pain is mainly caused by injuries to the ligaments and bones of the spine, and muscles are rarely involved. Relatively minor vertebral compression fractures or articular process fractures are often ignored due to the light trauma or unclear symptoms, resulting in chronic low back and leg pain. More than 90% of acute simple traumatic spinal low back and leg pain occurs in the sacroiliac joints of the lumbar sacrum. The lesions sometimes occur in one place and sometimes in two places at the same time. Therefore, simple traumatic spinal low back and leg pain can be divided into three types of low back and leg pain: lumbar sacral joint injury; sacroiliac joint injury; and combined injury of the lumbar sacral and sacroiliac joints.