Slipped disk. On the left, view of the vertebral column showing a slipped disk. On the right, slipped disk compressing a nerve root (at the top) or the spinal cord (at the bottom). A slipped disk is an abnormal protusion of an intervertebral disk. It is usually located at the level of the lumbar vertebrae. Following the repeated constraints exercised on the disk (bad posture, false movement, lifting heavy charges), the latter can get out partially of its usual lodging, forming a protusion inside the rachidian canal, compressing one of the nerve root or the spinal cord. This creates great pain that can extend up to the lower limbs (sciatica).