The normal adult lumbar spine has five segments, from top to bottom, the first to fifth lumbar vertebrae, the fourth and fifth lumbar vertebrae are usually anatomically located at the line of the highest point of the human iliac crest, which is usually called the level of the waistband of the pants. The lumbar 45 intervertebral body is also known as the lumbar 45 intervertebral disc, and this segment of the disc is the site where lumbar disc herniation is most likely to occur in clinical practice. The main reason is that the pressure on the lumbar 45 intervertebral disc is relatively high, and the weight of the entire upper body is pressed on the lumbar 45 intervertebral disc and the lumbar 5 sacral 1 intervertebral disc, and the lumbar 45 intervertebral disc has the greatest mobility, so the lumbar 45 intervertebral disc is most likely to herniate in clinical practice. In this case, a lumbar spine X-ray, CT or MRI is usually required to make a clear diagnosis.