Rotatory olisthesis in idiopathic scoliosis.

Lateral subluxation of one vertebral body upon another (rotatory olisthesis) has been associated with increased incidence of back pain in scoliosis. This study was undertaken to identify the presence of and characterize rotatory olisthesis and its association with the following parameters: age, sex, curve type, curve magnitude, level of occurrence, region within curves, primary vs. secondary curves, severity of slip, and association with pain. Charts of 636 patients were reviewed for the presence or absence of pain. Curve measurements and the occurrence of rotatory olisthesis were noted. Rotatory olisthesis was statistically unrelated to the occurrence of pain associated with idiopathic scoliosis. It was significantly associated with increasing age and curve magnitude. Lumbar curves with rotatory olisthesis were more likely to be associated with radicular pain.