Back Pain

What Is It?

Back pain can be a symptom of many different illnesses and conditions. The main cause of the pain can be a problem with the back itself or by a problem in another part of the body. In many cases, doctors can't find a cause for the pain. When a cause is found, common explanations include:

• Stress or injury involving the back muscles, including back sprain or strain; chronic overload of back muscles caused by obesity; and short term overload of back muscles caused by any unusual stress, such as lifting or pregnancy
• Disease or injury involving the back bones (vertebrae), including fracture from an accident or as a result of the bone-thinning disease osteoporosis
• Degenerative arthritis, a "wear and tear" process that may be related to age, injury and genetic predisposition.
• Disease or injury involving the spinal nerves, including nerve injury caused by a protruding disk (a fibrous cushion between vertebrae) or spinal stenosis (a narrowing of the spinal canal)
• Kidney stones or a kidney infection (pyelonephritis).

Rarer causes include:

• Inflammatory arthritis, including ankylosing spondylitis and related conditions
• A spinal tumor or a cancer that has spread (metastasized) to the spine from elsewhere in the body
• Infection, which may be in the disk space, bone (osteomyelitis), abdomen, pelvis or bloodstream.

Symptoms

Back pain varies widely. Some symptoms (often called "red flag" symptoms) may suggest that the back pain has a more serious cause. These include fever, recent trauma, weight loss, a history of cancer and neurological symptoms, such as numbness, weakness or incontinence (involuntary loss of urine or stool).