Pedicle Morphology of the Thoracic and Lumbar Spine in Scoliosis Associated With Chiari Malformation/Syringomyelia

Abstract

To investigate the morphology of pedicle in thoracic and lumbar spine in scoliosis associated with Chiari malformation/Syringomyelia-comparison with adolescent idiopathic scoliosis (AIS). Twenty-three patients of Lenke type 1 AIS and 21 patients of scoliosis associated with Chiari malformation/Syringomyelia with the similar curve type to Lenke 1 AIS underwent preoperational computed tomographic scans. Anatomic parameters were measured from T1 to L4, which included pedicle width, transverse pedicle angle, and chord length. Statistical comparison was performed within and between 2 groups. Pedicle width of patients with scoliosis associated with Chairi malformation/Syringomyelia ranged from 3 to 10.9 mm; pedicle width of convex side was wider than concave side in apex region and upper end vertebrae region (P<0.05), whereas in some thoracolumbar vertebrae(T11,L1,L3), pedicle width of concave side was wider than convex side (P<0.05). No statistical distinction was found between convex and concave side both in pedicle angle and chord length in scoliosis associated with Chiari malformation/Syringomyelia (P≥0.05), except several vertebrae. Statistic comparison between 2 groups showed no significance for the difference values of convex and concave pedicle width, transverse angle, and chord length (P≥0.05), except several vertebrae (T8, T12). Although the mean value of pedicle width of scoliosis associated with Chiari malformation/Syringomyelia was smaller than of AIS in every vertebra, statistical comparison showed no significance. The morphology of pedicle in scoliosis associated with Chiari Malformation/Syringomyelia was substantially different form normal, especially in apex region, where the change is similar to AIS; however, in thoracolumbar region, pedicle width of concave side was wider than convex side in several vertebrae. Alternative pattern was similar between 2 groups for both transverse pedicle angle and chord length.