Causes and prevention of slip disc

 Structure of backbone

The human backbone  or spine is divided into regions. There are seven vertebrae in the cervical region (neck), twelve vertebrae in the thoracic region (mid back) and five vertebrae in the Lumbar region (lower back). Beneath the Lumbar, Vertebrae are Sacrum and Coccyx.

The lumbar spine is a mobile structure fixed on the sacrum spine. Sacrum spine mobility is very minimal when compared to the Lumbar spine.

Each vertebrae has a solid part in front called the Vertebral body and a hole in the back. The vertebrae rest upon one-another. When lined up, these holes form the spinal canal. This canal serves as a protected passageway for the tightly packed bundle of nerves (spinal cord). It is 3/4 inch thick and runs from the back of the brain down the pelvis. Its nerve fiber carries instructions from the brain to the rest of the body ("move my right leg, empty my bladder etc.") and signals from the body are interpreted by the brain (sensations such as pain, itching, hunger etc.)

 What is disc

Special cartilages, called the discs, separate

the vertebrae. The discs are located in between two adjacent vertebrae bodies, just in front of the spinal cord. Functions of the disc are: to join the adjacent vertebrae, to allow movement between vertebrae, to act as a shock absorber, as a load distributor.

Inside portion of each disc consists of a soft semi fluid, "the nucleus"- Nucleus is surrounded and held together by a Cartilage, "the annular ring", The annular ring is the outer covering of the disc which is thicker anteriorly (front) and thinner posteriorly (back) and this is the reason for the disc to get herniated posteriorly (back) than anteriorly (front).

What is Slip Disc

 In reality, there is no such thing as slip disc. There is no way a dise can actually slip out of place. It merely buldges.

Some time the Nucleus, the central portion of the disc buldges backward towards the nerves. This is so called "SLIP DISC', but more precisely it may be called prolapsed or herniated disc.

Causes of slip disc

 The disc herniates for numerous reasons

(i) Lifting heavier objects and twisting the body.

(ii) Incidences of fall from a height.

(ii) Road traffic accidents.

(iv) Sedentary life style.

(v) Lack of exercise and weak abdominal muscles.

(vi) Improper postures of sitting etc.

Consequences

The herniated disc may slip either centrally or laterally causing pain in the lower back (Lumbar) or in the legs when the nerves in the spinal canal get compressed or irritated. In the Lumbar spine, the most common sites for dise herniation are "L3", "L4" and "L4-L5" segments. For example, when the "L4" disc herniates, the pain may be present at the outer side of the lower leg. When the disc gets slipped in the centre than lateral, it may cause generalized back pain with no particular leg pain.

The sciatic nerves service our legs, and when compressed and irritated, they may cause pain in the legs. Inflammation of the sciatic nerve is called sciatica.

Numbness

In several cases of neural impingement, numbness or partial loss of sensation may occur in the leg. When the spinal cord and its nerves gets injured or affected by a neurological disease, some may have paralysed legs and loss of bowel and bladder control and sexual function. The longer you wait for treatment, the longer that treatment will take. Therefore, don't ignore even the simple back pain.

Suggested treatment for less severe cases

1. Pain is the warning that some structure is to be damaged or has already sustained some damage. Be alert!

2. The immediate step, you may call it first aid is to take complete bed rest. Total rest is very good treatment. Sleeping on the side with knees drawn up or on the back with a pillow under bent knees minimises the pressure on the lower back.

3. Some may feel more comfortable by lying flat on the stomach with a pillow down the stomach.

4. Take breaks when sitting

The body is not designed for sitting more than 20 or 30 minutes. The compression of the disc is greatest when sitting for more than an hour, less when standing and least when lying down. Avoid sitting as much as possible to decompress the spinal segments. If it is convenient, get on your back several times a day or else, after every 30 minutes of sitting, stand up, arch your backward several times a day and walk around your work place for about three minutes. It will decompress the spine and reduce the severity of leg pain. Pressure on the disc for different postures is tabulated for general awareness.

Posture            Pressure on the Disc 

Lying Flat on the back-----Say 20 kg.

Standing Erect----------- 100 Kg.

Sitting with back supported---140Kg.

Sitting with trunk bent forward---200 Kg.