Back pain is one of the most common of all ailments. Eight out of 10 people experience a back problem at one time or another. Unfortunately, most people think about the health of their back only after a problem has occurred.

Problems with a vertebra, disc, muscle, ligament, or nerve in the back can cause back pain or stiffness. If a nerve within the spinal cord is affected, pain, numbness, or weakness may also appear in other parts of the body, such as the arms, fingers, hands, buttocks, legs, and feet, because the nerves that travel through the backbone connect to virtually every part of the body. Serious trauma to the back can lead to paralysis.

The lower section of the back, known as the lumbar region, is the most common site of back pain because this area absorbs more of the body's weight and stress.

Back problems may occur at any age, but are most common in people over age 30. As we age, the discs in the back lose water and elasticity. If activity is lessened, the back also loses strength. Unfortunately, once back problems exist, they tend to reoccur.

Sprains and strains result when the muscles (strains) or ligaments (sprains) are stretched or torn. Usually, such injuries result from misuse or overuse of the back. The soreness resulting from a sprain or strain in the back may immediately follow the injury or develop gradually. Sometimes there is associated muscle spasm. This is an involuntary contraction of muscles that causes sudden pain. A muscle spasm may result from poor posture, sitting in one position for an extended period of time, or from a back injury.

The term prolapsed disc refers to a condition in which a disc between two vertebrae bulges, or herniates. This can sometimes place pressure on nerve endings. In more severe cases, the disc actually ruptures, spilling some of its jelly-like contents. Often in the case of a prolapsed or ruptured disc, the sciatic nerve is affected. The sciatic nerves (there are two) are the largest nerves in the body. They begin in the lower back and extend to the legs. Someone with sciatica, therefore, often feels pain in the lower back as well as along the back of the hip and outer side of the leg.

Back problems are diagnosed in a variety of ways. Usually the physician will begin by taking the patient's medical history, including any previous incidences of back pain, and performing a physical examination. The physician may then choose to perform diagnostic studies, such as X rays or MRI. A large majority of cases can be sufficiently evaluated with a thorough history, physical exam, and occasionally X rays. MRIs are considered in stubborn and unusual cases or in those in which surgery is being considered.

Most back problems are self-limiting and alleviate themselves within a few days without a doctor's intervention. In these cases, the prescribed treatment may include:

Non-prescription pain reliever or anti-inflammatory medication. Decreased or modified activity. Chiropractic spinal adjustment, Physical therapy (heat/ice, massage, exercise). Protective supports (back brace or corset). Occasionally, a problem is more severe and may require: Complete bed rest. Prescription medication (taken orally or injected into the back). Surgery.

The spine is a complex assembly of bone and cartilage. It runs from the base of the neck to the tailbone, forming a protective ring around the spinal cord - the main pathway of the central nervous system.

The spine consists of more than 30 separate bones, called vertebrae. These vertebrae are stacked upon one another like building blocks and held together by ligaments. Between each vertebra are round, spongy cushions of cartilage, called discs, that serve to absorb shock and strain when the back bends, twists and stretches. The entire spinal structure is supported by the muscles and ligaments of the back, buttocks, legs, and neck. A normal spine has three curves: the cervical curve supports the neck and head; the thoracic curve supports the rib cage and most of the chest and abdominal muscles; and the lumbar curve is connected to the lifting muscles of the buttocks and legs.

When healthy, the spine permits us to pull, lift, stretch, and bend freely and without pain. It also serves as a protective casing for the spinal cord.

The vertebrae are irregularly shaped bones which stack together to form the spinal columns. The vertebrae are connected together by ligaments and muscles which control the degree of flexibility of the spine. The vertebrae are cushioned from each other by cartilage disks which act as shock absorbers to protect the vertebrae in the spine.

The vertebrae may be separate (cervical, thoracic, and lumber vertebrae), semi-articulated (as in some coccygeal vertebrae), or fused (as in the sacrum and coccyx). The typical vertebrae has a body of solid bony material, which supports the weight of the spine, and an arch, which forms the vertebral foramen. It is the adjoining vertebrae foramina which creates a canal down through the spinal column which houses and protects the spinal cord. The thoracic vertebrae feature facets to which the ribs attach, called costal facets (because of their relation to the ribs).