Causes of Back Pain
Nerve root syndromes are those that produce symptoms of nerve impingement (a nerve is directly irritated), often due to a herniation (or bulging) of the disc between the lower back bones. Sciatica is an example of nerve root impingement. Impingement pain tends to be sharp, affecting a specific area, and associated with numbness in the area of the leg that the affected nerve supplies.
- Herniated discs develop as the spinal discs degenerate or grow thinner. The jellylike central portion of the disc bulges out of the central cavity and pushes against a nerve root. Intervertebral discs begin to degenerate by the third decade of life. Herniated discs are found in one-third of adults older than 20 years of age. Only 3% of these, however, produce symptoms of nerve impingement.