What is a Herniated Disc?
Herniation of the nucleus pulposus (HNP) occurs when the nucleus pulposus (gel-like substance) breaks through the anulus fibrosus (tire-like structure) of an intervertebral disc (spinal shock absorber).

A herniated disc occurs most often in the lumbar region of the spine especially at the L4-L5 and L5-S1 levels (L = Lumbar, S = Sacral). This is because the lumbar spine carries most of the body's weight. People between the ages of 30 and 50 appear to be vulnerable because the elasticity and water content of the nucleus decreases with age.

The progression to an actual HNP varies from slow to sudden onset of symptoms. There are four stages: (1) disc protrusion (2) prolapsed disc (3) disc extrusion (4) sequestered disc. Stages 1 and 2 are referred to as incomplete, where 3 and 4 are complete herniations. Pain resulting from herniation may be combined with a radiculopathy, which means neurological deficit. The deficit may include sensory changes (i.e. tingling, numbness) and/or motor changes (i.e. weakness, reflex loss). These changes are caused by nerve compression created by pressure from interior disc material.

Progression of Herniated Disc
The extremities affected are dependent upon the vertebral level at which the HNP occurred. Consider the following examples:

• Cervical - Pain in the neck, shoulders, and arms
• Thoracic - Pain radiates into the chest
• Lumbar - Pain extends into the buttocks, thighs, legs

Cauda Equina Syndrome occurs from a central disc herniation and is serious requiring immediate surgical intervention. The symptoms include bilateral leg pain, loss of perianal sensation (anus), paralysis of the bladder, and weakness of the anal sphincter.

Diagnosis of a Herniated Disc
The spine is examined with the patient laying down and standing. Due to muscle spasm, a loss of normal spinal curvature may be noted. Radicular pain (inflammation of a spinal nerve) may increase when pressure is applied to the affected spinal level.

A Lasegue test, also known as Straight-leg Raising Test, is performed. The patient lies down, the knee is extended, and the hip is flexed. If pain is aggravated or produced, it is an indication the lower lumbosacral nerve roots are inflamed.

Other neurological tests are performed to determine loss of sensation and/or motor function. Abnormal reflexes are noted as these changes may indicate the location of the herniation.

Radiographs are helpful, but Computed Axial Tomography (CAT) or Magnetic Resonance Imaging (MRI) provides more detail. The MRI is the best method enabling the physician to see the soft spinal tissues unseen in a conventional x-ray.

Herniated Disc : Treatment and Recovery
Treatment
There are several conservative treatment options that may relieve the symptoms associated with a herniated disc. These include: alternate bed rest with ambulation and medications to reduce inflammation and pain. Non-steroidal anti-inflammatory drugs (NSAIDs) are often used for this purpose. Physical therapy may be incorporated into the patient's treatment plan. This might include exercise, massage, thermotherapy, as well as a device designed to support the back - a corset, back belt, or brace.

Remember that most patients with a herniated disc will get better without surgery.

Surgery
When no improvement is noted after a course of conservative treatment, surgery might be considered. However, remember that most patients with a herniated disc will get better without surgery.

A Discectomy is the surgical removal of part or the entire offending intervertebral disc. Microdiscectomy incorporates the use of a microscope to magnify the surgical field during removal of the disc.

Recovery
Whether the treatment course is conservative or operative, it is important to closely follow the instructions of your physician and/or physical therapist. Keep your weight close to ideal and continue to follow the exercise and/or rehabilitative program designed by your physical therapist at home.

The human spine is an extremely important structure in the body. It not only gives support to the body, but also allows mobility of the back in different directions. In addition to that, it houses the most important connection between the brain and the rest of the body - spinal cord.

The spine is made up of number of vertebral bones stacked one on top of the other. In between the vertebrae are discs which lend mobility to the spine and act as shock absorbers. On the back side, there are two small joints at each levels - called facet joints. This type of structure allows one to bend and rotate in different directions.

When the discs wear out, the spine at that particular level does not function normally and the back becomes painful. The degeneration of disc leads to a condition called Degenerative Disc Disease. Whereas large majority of such patients can be treated with painkillers, braces, physical therapy, small percentage of such patients do not respond to non-operative treatment and need surgery.

What are the surgical options?
There are two types of surgical option in such cases -

• Spinal Fusion
• Disc Replacement

Disc replacement is the most innovative and modern treatment that is now available. In spinal fusion surgery, the disc (which is a soft material between two vertebrae) is removed and the space is packed with bone graft. In due course of time, the bone creates a solid bony bridge across the two vertebrae. By doing away with movement, previously painful segment is made pain free.

However, the disadvantage of this procedure is that not only does this takes away normal movements of spine at that particular level but also ultimately leads to degeneration of higher level of spine which were uninvolved earlier on. This thus leads to pain in uninvolved segment over the course of time.

Modern innovative operative treatment for Degenerative Disc Disease is - Disc Replacement. After removing the disc, it is replaced by an artificial disc which thus restores movements in that particular segment and also does not make higher motion segment of vertebral column painful in the longer run.

What is an artificial disc ?
It is a three-piece medical device consisting of a sliding core sandwiched between two metal endplates. The sliding core is made from a medical grade plastic and the end plates are made from medical grade cobalt chromium alloy. These materials usually do not harm the human body and are used in many other medical implants such as total knee replacement implants.

WHO is a candidate for Artificial Disc? - The Artificial Disc is an alternative to spinal fusion for patients who have one or two degenerated, painful discs usually between L4/L5 and L5/S1. The disc deterioration is confirmed by history, x-rays and MRI Scan. Patients who have not responded positively to at least six months of non-surgical treatment such as pain medication, a back brace, or physical therapy are ideal candidates for an Artificial Disc. Patients who have had some type of minor lower back surgery may still receive the Artificial Disc.