Who is affected by back pain?
In the United States 85 to 90% of people experience back pain at some time during their lives. Back pain is the second most common reason people visit their family doctors (just after upper respiratory infections).
On any given day, almost 2% of the entire US work force is disabled by back pain. In people under 40 years of age, back pain is the most common reason for the inability to perform daily tasks. It also is the direct cause of enormous healthcare expenses, with estimates as high as $60 billion annually.
Pain that primarily affects the back is different from a spinal condition that results in mostly leg pain, a condition commonly called sciatica. Typically, sciatica is the result of a "pinched nerve" in the spinal column.
In most cases the cause of the sciatica is clear — for example, a disc problem or arthritis. The cause of an episode of back pain, on the other hand, often is more difficult to pinpoint and may be related to the discs, joints, or soft tissue supports (muscles, ligaments, and tendons).
What is acute back pain?
Acute back pain refers to a brief episode of pain that comes on suddenly. Most people recover from acute back pain within two weeks with minimal treatment. Using over-the-counter pain relievers — such as acetaminophen (Tylenol®) or ibuprofen (Advil®, Motrin®) — and getting back to normal activities as the pain permits are simple and effective treatments for most people with acute back pain.
What is chronic, persistent back pain?
Most back pain is relieved within a few days to a couple of weeks with simple treatment. When back pain persists beyond 2 to 4 weeks — which is chronic, persistent back pain — further medical evaluation is required. This evaluation focuses on a careful assessment of the patient's medical history and a thorough physical examination to identify, if possible, a precise cause of the pain. In rare cases, cancer or an infection is found. More commonly, the pain is related to the spinal joints, discs, or supporting muscles of the back.
What causes back pain?
Back strain is the leading cause (85% of cases) of back pain in the US. Other causes of back pain include:
- Disc herniation: A herniated disc is a rupture or tear of the cartilage that surrounds the vertebral discs. Pressure from the vertebrae above and below the affected disc squeezes the cushioning substance (nucleus pulposus) out of the disc. The nucleus pulposus can press against spinal nerve roots. This can cause severe leg pain and may cause nerve damage if not treated properly.
- Osteoarthritis/spinal stenosis: The constriction or narrowing of the vertebral canal, the space that surrounds the spinal column.
- Ankylosing spondylitis: A chronic inflammatory disease that first affects the spine and nearby structures. As the disease progresses, vertebrae will fuse together. This disease has a strong hereditary (runs in the family) tendency and primarily affects men under 30 years of age.
- Spondylolisthesis: Spondylolisthesis is the partial forward movement (dislocation) of one vertebra over the one below it. Usually, the fifth lumbar (low back) vertebra is dislocated over the first sacral (tail bone) vertebra.
- Infection (less than 1% of cases).
- Cancer (less than 1% of cases).
- Trauma: An injury due to an accident or fall may cause a fracture or muscle strain.
- Non-spinal causes: Non-spinal causes of low back pain include abdominal aortic aneurysms, kidney stones, infection, or perforating stomach ulcer.