WHAT IS CHRONIC BACK PAIN?
The bones of the back, also called the spinal column, support a person’s upper body and give it flexibility. The spine is divided into 3 main sections; the neck or cervical region, the middle region or thoracic region which is the back of the chest cavity, and the lumbar region or lower back. The bones of the spine allow for free and easy twisting and bending movement. The spine consists of 24 bones called vertebrae (pronounced ver-te-bray). There are seven vertebrae in the neck, 12 in the upper (thoracic – pronounced thor-a-sic) spine, and five in the lower (lumbar) spine.
A triangular bone called the sacrum is immediately below the lumbar vertebrae. The sacrum is actually comprised of five bones fused together. The sacrum and the two pelvic bones form the base of the trunk and are called the pelvis. The tailbone (coccyx – pronounced cahk-sics) is actually made of three or four very small bones. All the bones in the back are kept in good alignment by support of the muscles attached to the spinal bones and are also supported by the strong muscles of the abdomen. A healthy back is straight, strong, flexible and free of pain.
Back pain is usually defined as either acute or chronic. Doctors may diagnose low back pain as acute if it lasts less than a month. Most cases clear up in a few days without medical attention, although recurrence after a first attack is common. If the pain persists for over 3 months, it is considered chronic back pain, this constitutes only 1% to 5% of back pain cases.
The most common area of back pain is the lumbar spine. A lumbar strain is said to occur when the muscles of the low back become tense and develop spasm. This may occur after even a minor strain or injury.
Herniated (pronounced her-nee-a-ted) discs are also a common source of back pain. Small cushions called intervertebral discs, separate vertebrae in the back from each other. Eeach disc is made up of a jelly-like substance that is surrounded by a firm fibrous sheath and 80% of the disc is water, which makes it very elastic. A disc does not contain any blood, and relies on nearby blood vessels to keep it nourished. A herniated disc occurs when the fibrous sheath between the vertebrae tears and the jello-like substance leaks out.. The gelatinous extrusion can cause pressure on the nerves in the area. This may produce muscle spasm at the site, or pain or weakness in the leg as the nerve.
Back pain is the most prevalent medical disorder in industrialized societies.
Back pain can develop anywhere from the neck to the lower spine. The pain can be localized or spread across a wide area and radiate from a central point. Muscle spasms are commonly associated with back pain arising from any cause. Some people also get pain or weakness in a leg as a result of back injury.
Poor posture and weak supporting muscles are a common cause of back pain. The most common reason for poor muscle strength is lack of physical exercise. As we get older, the jello structure of the discs have a reduced water content, the discs reduce in size, loose some of their elasticity and cause the bones of the spine to settle on each other more snugly. This increased pressure between the bones can be an irritant that can be a cause of pain. The resulting pain may first appear as stiffness that disappears when you get up and move around. After months the pain and stiffness may last for longer periods.
Stressors to the spine such as can occur when lifting heavy objects without attention to keeping the back straight and bending knees, is also a frequent cause of back pain. When you lift a heavy object increased pressure is put on your lumbar spine. If you lift the weight incorrectly and have it positioned far in front of your spine, your back muscles have to exert a tremendous force to lift the body into an upright position. This can cause the muscles to strain or a disc to herniate.
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