Lumbar disc herniation Lumbar disc herniation occur in the lower back, most often between the fourth and fifth lumbar vertebral bodies or between the fifth and the sacrum. Symptoms can affect the lower back, buttocks, thigh, anal/genital region (via the Perineal nerve), and may radiate into the foot and/or toe. The sciatic nerve is the most commonly affected nerve, causing symptoms of sciatica. See: http://-/Sciatica The femoral nerve can also be affected and cause the patient to experience a numb, tingling feeling throughout one or both legs and even feet or even a burning feeling in the hips and legs. A hernia in the lumbar region often compresses the nerve root exiting at the level below the disk. Thus, a herniation of the L4/5 disc will compress the L5 nerve root.(54)LOE 3A
Over time, with repeated neck or back injuries, the process of tearing and scarring may weaken the disc wall. As people age, the nucleus pulposus (center of the disc) becomes damaged and loses its water content. This fluid is needed to keep the disc functioning as a shock absorber. If the nucleus pulposus is not able to act as a cushion, the nucleus collapses and the vertebrae above and below the damaged disc slide closer together. This improper alignment causes the facet joints (the areas where the vertebrae touch) to twist due to an unnatural position. In time, this awkward positioning of the vertebrae may create bone spurs or osteophytes . If bone spurs grow into the spinal canal, they may pinch the spinal cord and nerves, a condition called spinal stenosis. If the outer annulus tears and a piece of the nucleus pulposus moves through the tear, a disc herniation may pinch the spinal cord and nerves. The site of the injury may be painful. Some people experience a radiculopathy as pain, numbness, or tingling in the arms or legs.
The popular term slipped disc is a misnomer, as the intervertebral discs are tightly sandwiched between two vertebrae to which they are attached, and cannot actually "slip", or even get out of place. The disc is actually grown together with the adjacent vertebrae and can be squeezed, stretched and twisted, all in small degrees. It can also be torn, ripped, herniated, and degenerated, but it cannot "slip".  Some authors consider that the term "slipped disc" is harmful, as it leads to an incorrect idea of what has occurred and thus of the likely outcome.    However, during growth, one vertebral body can slip relative to an adjacent vertebral body, a deformity called spondylolisthesis .