The bones (vertebrae) that form the spine in the back are cushioned by discs. These discs are round, like small pillows, with a tough, outer layer (annulus) that surrounds the nucleus. Located between each of the vertebra in the spinal column, discs act as shock absorbers for the spinal bones.
A herniated disc (also called bulged, slipped or ruptured) is a fragment of the disc nucleus that is pushed out of the annulus, into the spinal canal through a tear or rupture in the annulus. Discs that become herniated usually are in an early stage of degeneration or the body has endured some type of traumatic, acute impact. The spinal canal has limited space, which is inadequate for the spinal nerve and the displaced herniated disc fragment. Due to this displacement, the disc presses on spinal nerves, often producing pain, which may be severe.
Herniated discs can occur in any part of the spine. Symptoms vary greatly, depending on the position of the herniated disc and the size of the herniation. If the herniated disc is not pressing on a nerve, the patient may experience a low backache or no pain at all. If it is pressing on a nerve, there may be pain, numbness or weakness in the area of the body to which the nerve travels. Typically, a herniated disc is preceded by an episode of low back pain or a long history of intermittent episodes of low back pain.
Lumbar spine (lower back): Sciatica/Radiculopathy frequently results from a herniated disc in the lower back. Pressure on one or several nerves that contribute to the sciatic nerve can cause pain, burning, tingling and numbness that radiates from the buttock into the leg and sometimes into the foot. Usually one side (left or right) is affected. This pain often is described as sharp and electric shock-like. It may be more severe with standing, walking or sitting. Straightening the leg on the affected side can often make the pain worse. Along with leg pain, one may experience low back pain; however, for acute sciatica the pain in the leg is often worse than the pain in the low back.
Cervical spine (neck): Cervical radiculopathy is the symptoms of nerve compression in the neck, which may include dull or sharp pain in the neck or between the shoulder blades, pain that radiates down the arm to the hand or fingers or numbness or tingling in the shoulder or arm. The pain may increase with certain positions or movements of the neck.