bulging disc L5 S1

by Nathan Wei, MD, FACP, FACR

Nathan Wei is a board-certified rheumatologist and author of the Second Opinion Arthritis Treatment Kit. It's available exclusively at this website... not available in stores.

Click here: Second Opinion Arthritis Treatment Kit

The disc is a complex structure that carries two principal functions: connects two vertebra together (while permitting some motion) and provides a shock absorbing function.

The disc is located between two vertebra and looks like a very solid “doughnut” made of multiple outer fibrous layers (called the 'annulus' which means "ring") while containing a jelly-like substance in the middle (called the 'nucleus').

With age, the intervertebral disc may lose water and become dried out. As this happens, the disc compresses. This may lead to the deterioration of the tough outer ring allowing the nucleus, or the inside of the ring, to bulge out. This is called a bulging disc.

A ruptured disc means that an unusual and excessive load has been applied on a disc resulting in the rupture of all or most of the layers of the annulus. The consequence is a disruption of the binding ligament and leakage of the jelly (nucleus pulposus) out of the boundaries of the annulus. As a consequence the two vertebrae connected by the disc which suffered the injury are no longer smoothly bound together and a combination of instability and nerve irritation can lead to severe back pain.

Pain may be confined to the low back or, more commonly, may be radicular- meaning it radiates down the leg. The most common cause of radicular pain is herniation of the lumbar disc. The incidence is 1-2% of patients with low back pain (LBP). 85% of herniations occur at L4-5 and L5-S1. The peak incidence of herniated lumbar disks in adults is between the ages of 30 and 55 years.

The posterior longitudinal ligament is thinnest at L2-L5. Normally, the weight of the body is supported by the anterior spinal column and bony vertebrae, along with the interspersed fibrocartilaginous discs. The disc account for 1/3 of the total height of the lumber spine, compared to 1.5 of the total height elsewhere in the spinal column.

Fibrous tissues of the disc is thinnest posteriorlly, encouraging posterior bulging. Posterior primary division irritation usually leads to LBP in the paraspinal muscle area. Anterior division irritation leads to classic radicular pain.

Radicular pain usually presents with sharp, stabbing radiating pain, started with lifting or twisting event. Pain can be shooting in character, and increased with physical activity, especially lifting, bending, sitting and exercises that increase intra-abdominal pressure.

Irritation of neurological structures is manifested as motor, reflex, or sensory dysfunction in the lower extremities and rarely as bowel or blader dysfunction.

Sciatica, a sharp or burning pain radiating down the posterior or lateral aspect of the leg (usually to the foot or ankle), is often associated with numbness or paresthesia. Sciatica has such a high sensitivity (0.95) that its absence makes a clinically important lumbar disk herniation unlikely.

How to get better health insurance for less. Read our advice on how to get free, no obligation affordable health insurance quotes and improve your health coverage while saving money too. Get Free Health Insurance Quotes

Bulging disc L5 S1