Lumbar disc herniation
Lumbar disc herniations occur in the lower back, most often between the fourth and fifth lumbar vertebral bodies or between the fifth and the sacrum. Here, symptoms can be felt in 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. 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 a burning feeling in the hips and legs. A herniation in the lumbar region often compresses the nerve root exiting at the level below the disc. Thus, a herniation of the L4–5 disc compresses the L5 nerve root, only if the herniation is posterolateral.
Cervical disc herniation
Cervical disc herniations occur in the neck, most often between the fifth and sixth (C5–6) and the sixth and seventh (C6–7) cervical vertebral bodies. There is an increased susceptibility amongst older (60+) patients to herniations higher in the neck, especially at C3–4. Symptoms of cervical herniations may be felt in the back of the skull, the neck, shoulder girdle, scapula, arm, and hand. The nerves of the cervical plexus and brachial plexus can be affected.
Intradural disc herniation
Intradural disc herniation is a rare form of disc herniation with an incidence of 0.2–2.2%. Pre-operative imaging can be helpful for diagnosis, but intra-operative findings are required for confirmation.
It is increasingly recognized that back pain resulting from disc herniation is not always due solely to compression of the spinal cord or nerve roots, but may also be caused by chemical inflammation.There is evidence that points to a specific inflammatory mediator in back pain: an inflammatory molecule, called tumor necrosis factor alpha (TNF), is released not only by a herniated disc, but also in cases of disc tear (anulus tear) by facet joints, and in spinal stenosis. In addition to causing pain and inflammation, TNF may contribute to disc degeneration.
Terms commonly used to describe the condition include herniated disc, prolapsed disc, ruptured disc, and slipped disc. Other conditions that are closely related include disc protrusion, radiculopathy (pinched nerve), sciatica, disc disease, disc degeneration, degenerative disc disease, and black disc (a totally degenerated spinal disc).
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.
Spinal disc herniation is known in Latin as prolapsus disci intervertebralis.
Another information you can find in chapter III.