Human Spinal Deformities Using 3d Reconstruction Techniques

Literature Survey on Human Spinal Deformities using 3D Reconstruction Techniques Introduction: Spine and its deformities: Scoliosis is a complex three-dimensional (3-D) deformation of the trunk that requires orthopedic treatment in 5 out of 1000 persons [1]. It is described as a lateral deviation of the spine (Fig. 1), combined with asymmetric deformation and axial rotation of the vertebrae, deformation of the rib cage and possibly of the pelvis. The human spine is divided into cervical (7 vertebrae C1 - C7), thoracic (12 vertebrae Tl - T12), and lumbar (5 vertebrae L1 - L5) sections above a fused sacrum (Fig. 2). While the spine normally has no lateral curvature, there are normal side-view curves including lumbar lordosis, thoracic kyphosis and cervical lordosis. Scoliotic curves are considered thoracic when the apex lies between T2 and T11, thoracolumbar at T12-L1, and lumbar from L2-L5. Each vertebra consists of an anterior weight-bearing vertebral body and posterior elements that protect the spinal cord and enable muscular and ligamentous attachments (Fig. 3). Particularly in severe scoliotic curves, asymmetric loads on the vertebrae encourage asymmetric growth of the vertebral elements, with one result being that despite a substantial underlying spinal curve the spinous processes may deform to produce a relatively straight line on the back surface. The spine, composed of vertebrae connected by fluid-filled intervertebral discs, is a loose and