The role of imaging in the diagnosis of postural disorders related to low back pain.

The function of the spine in humans is support of the body in an upright position, whilst defying gravity, conserving energy and permitting purposeful movement. Low back pain may either be caused by or result in postural disorders. It is an important cause of lost workdays in the industrialised world, with accompanying social and economic implications, and is a common and disabling problem in many sports. Increased awareness of the potential benefits of exercise, together with a change in attitudes in professional sport (placing greater pressure upon individuals to achieve more spectacular results), have resulted in increased pressure on medical services. This article reviews the examination protocols and clinical applications of the diagnostic imaging modalities available for the evaluation and diagnosis of postural disorders related to low back pain. Conventional radiography continues to be of value in demonstrating skeletal relationships and quantifying spinal kinematics. Computed tomography (CT) is widely available and highly accurate in the evaluation of disc herniation and spinal stenosis. Magnetic resonance imaging (MRI) demonstrates discs and the spinal cord with superb morphological accuracy, is painless and noninvasive, and has no known adverse effects or morbidity. It is the most accurate and sensitive modality for diagnosis of subtle occult changes in low back pains in patients where early preventative measures can be adopted to avoid further damage.