The lumbar spine corresponds to spine in the “small of the back.” It is made of five separate
vertebrae, each of which are separated by a cushion called a disc. This cushion
is made of a soft spongy material that is contained within a very tough fibrous
outer layer. A disc herniation occurs when the tough outer layer develops a weak
spot and allows the inner spongy tissue to leak out. The disc material typically
leaks against a spinal nerve, causing both a chemical irritation and direct pressure
on the nerve. The nerves in the lumbar spine travel to various places in the buttocks
and legs, so the irritation of one of these nerves can be the source of leg pain,
called sciatica.
About 2% of the general population experience herniated discs in the lumbar section
of the back. They can happen to anyone at any time. In fact, many patients say
they “just woke up and could not get out of bed” without any prior injury. However,
there are certain factors associated with disc herniations, including heavy lifting,
improper lifting techniques, stressful occupations and cigarette smoking.
Symptoms
Most patients report moderate levels of back pain prior to the onset of the leg
pain that is present in almost any position. However, disc herniations can occur
without injury, and even without back pain. The symptoms in some patients may
include only leg pain or weakness. The specific location of leg pain and weakness depends
on which nerve is irritated.
Treatments
Sixty to seventy percent of patients with lumbar disc herniations have resolution
of most of their symptoms within eight to12 weeks using conservative treatments,
including bed rest, over-the-counter anti-inflammatory medication, physical therapy
and home exercise programs. For severe symptoms, a short course of narcotics or
muscle relaxants may be used. A series of oral steroids or epidural steroid injections into the spine also may calm the inflammation of the nerves and give temporary
relief of the buttock and leg symptoms.
Only about 30 percent of patients with a disc herniation and sciatica will need
a spine operation. However, those with loss of bowel or bladder function, major
muscle weakness, and excruciating, uncontrollable pain may benefit from surgical
intervention. A persistently symptomatic patient should not wait more than 12
weeks to consult with a surgeon, because the window of opportunity for benefit
from surgery begins to narrow.
|