Where does the “pain” of low back pain come from? Are there nerves and blood vessels in the discs? What is the role of the lumbar discs? Let’s find out today! Are there nerves and blood vessels in the intervertebral disc? There are no nerves in the inner fibrous ring and nucleus pulposus of a normal disc, and only free nerve endings pass through the outer fibrous ring of the disc; these free nerve endings are mainly the tiny branches of the sinus nerve. The sinus nerve is a branch of the lumbar nerve that climbs on the outer layer of the fibrous ring of the disc and can cause back pain when the disc bulges outward and irritates the sinus nerve. The lack of blood supply in the intervertebral disc and the infiltration of nutrients from the cartilage plate make the disc less capable of repair after injury. What is the role of the lumbar intervertebral disc for people? The intervertebral disc plays the role of connecting the upper and lower vertebral bodies of the disc, and constitutes the unit of motion when the human body bends and turns; because the disc has a certain thickness, it can maintain the height of the spine, and the height of the entire disc accounts for about one-fifth of the length of the spine. The intervertebral disc has elasticity and ductility, which can play a role in force transmission and cushioning. The discs vary in thickness from one part to another and maintain the physiological curvature of the spine, which is important to the human body. In short, intervertebral discs have important physiological functions.