The S3 vertebra is the third vertebra of the sacral spine and is located 3-5 cm above the gluteal groove. The spine is divided from top to bottom into the cervical vertebrae (C) with 7 blocks, the thoracic vertebrae (T) with 12 blocks, the lumbar vertebrae (L) with 5 blocks, and the sacral vertebrae (S) with 5 blocks. The 5 sacral vertebrae of the human body are synthesized into a single bone. It is the posterior wall of the pelvis. It is connected to the fifth lumbar vertebrae on the top and to the tailbone on the bottom. The S3 vertebrae, also known as the 3rd sacral vertebrae, are in the tailbone area of the body, with a body position of 3 to 5 centimeters above the groin. The third sacral vertebrae, if there is a fracture, the general situation to bed rest, do not need special treatment, lying down easy to be squeezed, it is recommended that the side position to avoid local weight bearing, to reduce the pain symptoms. If the body appears uncomfortable symptoms, should go to the hospital in time for examination, to clarify the cause of the disease and follow the doctor’s instructions for standardized treatment.