Introduction

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Low Back Pain

Low back pain is usually defined as either acute or chronic.

• Acute low back pain lasts less than a month and is not caused by serious medical conditions. Most cases clear up in a few days without medical attention, although recurrence after a first attack is common.
• Chronic low back pain persists beyond 6 months. It constitutes only 1 - 5% of all low back pain cases.

The source of low back pain can result from many of the following problems.

• Injuries and small fractures in the spine
• Muscle spasm
• Rupture in the weakened disk (herniated disk)
• The facets (z-joints) can become misaligned or deteriorate
• The spinal canal itself can become narrowed (spinal stenosis)
• Scar tissue in the lower spine
• Tears in muscles and ligaments that support the back

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Sciatica

At some time, up to 40% of people experience pain called sciatica. This condition occurs when the sciatic nerve is trapped or inflamed.

The Sciatic Nerve. The sciatic nerve has an extensive pathway.

• It first branches from the nerve roots that descend off the lowest part of the spinal cord (in the lumbar and sacral areas). Each of the two branches of the sciatic nerve is about as wide as a thumb.
• Each branch of the nerve threads through the pelvis and deep into either side of the buttocks.
• The nerve branches then pass down each hip and along the back of each thigh to the foot.

Causes of Sciatica. A herniated disk pressing on the sciatic nerve is the most common cause of sciatica, although spinal stenosis or other vertebral abnormalities that press on the sciatic nerve can also cause pain.

Symptoms of Sciatica

Pain due to sciatica can vary widely. It may feel like a mild tingling, dull ache, or a burning sensation. In some cases, the pain is severe enough to cause immobility.

The pain most often occurs on one side. Some people experience sharp pain in one part of the leg or hip and numbness in other parts. The affected leg may feel weak.

The pain often starts slowly. Sciatica pain may get worse:

• At night
• After standing or sitting for long periods of time
• When sneezing, coughing, or laughing
• After bending backwards or walking more than 50 to 100 yards (particularly if it is caused by spinal stenosis)

Sciatica pain usually goes away within 6 weeks, unless there are serious underlying conditions. Pain that lasts longer than 30 days, or gets worse with sitting, coughing, sneezing, or straining may indicated a longer recovery.