[Biomechanics of the intervertebral disc : Consequences of degenerative changes]

The intervertebral disc represents the flexible connection between two adjacent vertebral bodies. Intervertebral discs, therefore, give the spine its enormous range of motion. At the same time, intervertebral discs distribute the load evenly over the bony vertebral bodies to ensure load transfer from the upper body to the pelvis, provide sufficient stability, and absorb shocks during everyday movements as well as under extreme loads. The two tissue regions of the intervertebral disc, the central fluid-rich core (nucleus pulposus) and the lamellae of the outer fibrous ring (annulus fibrosus) experience different stresses under load and movement. This article summarizes current knowledge on the biomechanical properties of the intervertebral disc and explains how these are altered by degeneration and which surgical treatment options for degenerated and herniated discs are advisable from a biomechanical perspective.