The spinal column is a series of 24 bones called vertebrae running from the neck to the pelvis. Seven cervical vertebrae support the neck, 12 thoracic vertebrae connect to the rib cage and five lumbar vertebrae support the lower back. The spinal column protects the spinal cord, the bundle of nerves that runs from the brain to the pelvis. The vertebrae are separated and cushioned by rubbery disks filled with a gelatinous substance. Trauma or strain can cause a disk to herniate--move out of place--or rupture, resulting in pressure on the nerve. The lower back, or lumbar region, is the most common area for a herniated disk. The lumbar region of the back is the most common area for a herniated disk. The risk of a herniated disk is higher in men who are middle-aged or older.
Back Pain
Although a patient with a herniated lumbar disk may be unaware of it, more often he will complain of mild to severe pain on one side, in the lower back region. The pain often starts slowly and may worsen at night, according to the Mayo Clinic, or when sneezing, coughing, bending backward or walking more than a few yards.
Sciatica
The sciatic nerve is the main nerve traveling down the leg. When a herniated disk presses on the sciatic nerve, it causes a radiating, aching pain that starts in the buttock and extends down the back or side of one leg, according to the Mayo Clinic. The patient may also complain of numbness or tingling in the buttock and down the back of the leg. The pain may range from mild to severe enough to cause immobility. It may get worse at night, after sitting or standing for long periods, or when sneezing, coughing, bending backward or walking. It usually resolves after six weeks.
Muscle Weakness
A herniated disk may cause muscle weakness that is noticeable when lifting the leg or standing on the toes on the affected side. In severe cases, the patient may not be able to stand or walk normally.
Cauda Equina Syndrome
Cauda equina syndrome, according to the New York Times, is caused by pressure on the cauda equina, the four strands of nerves leading through the lowest part of the spine. Cauda equina syndrome is an emergency condition that can cause permanent damage to bladder function if not treated surgically. Symptoms include dull back pain; weakness or numbness in the buttocks, between the legs, or in the inner thigh, backs of legs or feet; inability to control urination and defecation; and sometimes fever.
