In most known cases, pain begins with an injury, after lifting a heavy object, or after making a sudden movement. Not all people have back pain after such injuries, however. In the majority of back pain cases, the causes are unknown.
Intervertebral disks begin deteriorating and growing thinner by age 30. One-third of adults over 20 show signs of herniated disks (although only 3% of these disks cause symptoms). As people continue to age and the disks lose moisture and shrink, the risk for spinal stenosis increases. The incidence of low back pain and sciatica increases in women at the time of menopause as they lose bone density. In older adults, osteoporosis and osteoarthritis are also common. However, the risk for low back pain does not mount steadily with increasing age, which suggests that at a certain point, the conditions causing low back pain plateau.
Jobs that involve lifting, bending, and twisting into awkward positions, as well as those that cause whole-body vibration (such as long-distance truck driving), place workers at particular risk for low back pain. The longer a person continues such work, the higher their risk. Some workers wear back support belts, but evidence strongly suggests that they are useful only for people who currently have low back pain. The belts offer little added support for the back and do not prevent back injuries.
A number of companies are developing programs to protect against back injuries. However, studies have been mixed on the outcome of company interventions. Employers and workers should make every effort to create a safe working environment. Office workers should have chairs, desks, and equipment that support the back or help maintain good posture.
Low back pain accounts for significant losses in workdays and dollars. According to the Bureau of Labor Statistics, back pain was responsible for around 60% of cases of people missing work due to pain involving the upper body.
Medical Conditions in Children
Review Date: 04/07/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.