Scoliosis is a spinal deformity that is defined as a pathological frontal curvature with decrease of the physiological sagittal curvature, and must be evaluated three-dimensionally. We present a morphologic curve to express the three-dimensionalconfiguration of a scoliotic spine from two plane radiograms, and evaluate spinal curvature three-dimensionally. The morphologic curve can be formulated from two plane curves approximating the frontal and sagittal arrangements of the centers of vertebral bodies. Furthermore, the Cobb angle, which is widely used in orthopaedics, can be calculated three-dimensionally as the maximum angle between two tangent vectors of the morphologic curve. In 45 spines with idiopathic scoliosis, the configurations ofspines were extremely well approximated by the morphologic curves. Three-dimensional Cobb angle was significantly larger than frontal Cobb angle. Since the three-dimensional Cobb angle includes the sagittal and frontal curvatures, it can be used forthree-dimensional evaluation of the scoliotic spine.
展开▼
