Lumbar Disc Herniation (Slipped Disc)
A condition which refers to a problem with a rubbery disc between the spinal bones.
This condition occurs when the soft centre of a spinal disc pushes through a crack in the tougher exterior casing.
Some herniated discs cause no symptoms. Others can irritate nearby nerves and result in pain, numbness or weakness in an arm or leg.
What is the intervertebral disc?
The lumbar disc consists of an outer tough structure called annulus fibrosus and a centrally placed jelly like material called nucleus pulposus.
Behind this are neural structures that are responsible for power and sensations in the lower limbs along with control of bladder and bowel functions.
What is a disc herniation or slipped disc?
The lumbar disc starts degenerating form the early 20s and progresses based on the genetic predisposition of the individual. This degeneration is universal and is part of the ageing process. Lumbar disc herniation is the failure of the tensile annulus (tough outer covering of the disc) to contain the central nucleus pulposus (central jelly like disc material). This usually occurs due to weakening of the annulus as part of degeneration process.
Symptoms of a disc herniation
Patients suffering from this problem usually have sudden onset of low back pain and one sided (or bilateral) leg pain. This leg pain (SCIATICA) most commonly radiates from the buttocks to the back and side of thigh to the back and side of leg and the dorsum of the foot. This leg pain may vary in distribution based on the nerve that is affected. The leg pain is due to affection of the nerve root due to pressure by a herniated disc. The neural compression may also lead to weakness and abnormal sensations (pins and needles) in the legs.( Forward movements of the spine, posture, coughing, sneezing, etc can influence this pain)
Investigation for evaluating a Disc herniation
If you are suffering from any of the above symptoms, get yourself checked by a spine specialist. If your specialist feels that further investigations are required, he/she may suggest an MRI scan. This is the best radiological investigation to confirm the diagnosis.
Types of lumbar disc herniations
Lumbar disc herniations are classified by various means based on the site (central, lateral
recess, foraminal, extra foraminal) and degree of herniation (protrusion, extrusion,
sequestration)
Treatment for Lumbar disc herniation
A wide variety of treatment options are available for treating lumbar disc herniations. Always consult your spine surgeon before starting your treatment. Majority of patients respond well to physiotherapy, back exercises, rest, analgesics etc. Surgery may be required in patients who have neurological deficit or those who do not respond to other treatment.
Discectomy
This is a technique of decompressing the nerve root by excising the offending herniated disc . This relieves the radicular pain (buttock and leg pain) almost instantaneously.
Multiple approaches are available for this procedure and the choice is patient and case dependant !
Postop restrictions after Discectomy
After undergoing discectomy patients are asked to avoid lifting weights, forward bending and jerks to the back for a few weeks. Walking and back exercises are encouraged after surgery.
Complications of Surgery?
The two complications, which need to be avoided, are infection and damage to nerve root. The chances of these are about 1%. Appropriate care and surgical expertise avoids these complications.
Risk Factors/Prevention
As people age, the water content in the disks decreases, they shrink and become less flexible. Conditions that can weaken the disk include:
- Improper lifting
- Smoking
- Excessive body weight that places added stress on the disks (in the lower back). Lack of exercises as part of the lifestyle also predisposes.
- Sudden aggressive activity
- Repetitive strenuous activities