Other Causes Of Back Problems - Why Does Your Back Hurt: Back Pain

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Other causes of back problems

Low back pain may also develop for a variety of other reasons. Some of the more common examples include arthritis, osteoporosis, and pregnancy. Less common causes of back pain include spondylolisthesis, congenital problems, and disorders affecting other organs.

Arthritis

Degenerative arthritis of the facet joints is common among older people. It often causes varying degrees of back pain, usually intermittent and chronic. Ankylosing spondylitis (from the Greek ankylos, for bent, and spondylos, for vertebra) — a condition in which the spine becomes inflamed and stiff — is the most common of these arthritic ailments. This disorder, which usually begins before age 40, is more common and more aggressive in men. When mild, it can be mistaken for a back strain or a disk problem. Sometimes, people with this condition have pain in both sides of their lower back or pelvis. When severe, it can cause increasing pain over time, eventually resulting in fusion of the spinal joints and a completely rigid back.

Osteoporosis

In older people, especially women who are postmenopausal, bones become weaker, more porous, and more susceptible to breaks. In such people, one or more vertebrae may fracture even if no actual injury has occurred. Sometimes something as innocuous as lifting a gallon of milk or sneezing can cause a vertebral fracture. This type of fracture is also referred to as a compression fracture because the broken vertebra may collapse under pressure, causing the spine to compress (see Figure 5).

Figure 5: A look at normal and compressed vertebrae Normal vertebrae are upright, but if several collapse, you may develop a curvature of your spinal column.

When a compression fracture occurs, back pain — sometimes severe and disabling — comes on suddenly. The discomfort tends to be localized in the region of the affected vertebra, but it may radiate around one or both sides of your trunk. While movement increases pain, lying down probably relieves it.

Spinal fractures are the most common of osteoporotic breaks. Each year, osteoporosis causes 750,000 such fractures. Amazingly, as many as two-thirds of these fractures go undiagnosed, with the accompanying pain attributed to general back pain.

Spinal fractures can result in a loss of height, and, more serious, a rounding of the back commonly known as dowager's hump. Sometimes wearing a back brace can help ease the pain of a fracture.

Pregnancy

Pregnancy can cause backache, especially in the final trimester. And although the discomfort usually recedes and disappears after childbirth, it can become chronic. The exact reason for this kind of low back pain isn't known. But several factors probably contribute: Ligaments normally loosen during the third trimester; abdominal muscles stretch and weaken; and carrying the fetus and giving birth stress the back. In addition, the task of caring for — and carrying — an infant or small child further taxes the lower back.

Spondylolisthesis

A defect in the bony posterior elements of one vertebra sometimes allows the front portion of that vertebra as well as the vertebra above it to slip forward out of normal alignment with the spine below. The result, known as spondylolisthesis, can cause severe low back pain, as well as discomfort in your thighs and hips. You may also experience sciatica, usually in both legs. Certain types of athletes — including weight lifters, football players (particularly interior linemen), gymnasts, and sumo wrestlers — are especially prone to this defect.

Deformation, molding, or yielding of the bone of the facet joints causes a condition called degenerative spondylolisthesis. This defect occurs because of gradual wear and tear, rather than heavy lifting or flexion-extension movements (such as those done by gymnasts). People with diabetes have four times the average risk for this problem.

Congenital abnormalities

The formation of the spine during fetal development is a complex process. A number of variations may occur during development, and even show up on x-rays later on, but fortunately most of them are not significant.

Disorders of other organs

A backache may also be caused by an aneurysm — a ballooning weakness — of your aorta, the very large blood vessel that carries blood from your heart to your lower trunk and legs. Disorders of various abdominal or pelvic organs, including the pancreas, kidneys, or uterus, can also cause back pain. Pain in the back from conditions that have nothing to do with the spine or related structures is usually called referred pain. Ordinarily, such pain is not affected by motions or activities that put stress on the spine. Moreover, x-rays and other diagnostic tests show nothing to implicate the back.

Last updated:	January 23, 2007