Vertebral Body Morphology in Neuromuscular Scoliosis with Spastic Quadriplegic Cerebral Palsy

Abstract

Background/Objectives: The distorted vertebral body has been studied in scoliosis; however, there is little knowledge about the difference between neuromuscular and idiopathic scoliosis. This study aimed to investigate the vertebral body morphology in patients with spastic quadriplegic cerebral palsy and scoliosis (CP scoliosis) and compare them with those of apex- and Cobb angle-matched patients with adolescent idiopathic scoliosis (AIS). Methods: Thirty-four patients with CP scoliosis and thirty-two patients with AIS were included. The pedicle diameter, chord length, and vertebral body rotation were evaluated at one level above the apex, one level below the apex, and at the apex using a reconstructed computed tomography scan. The apex of the curve and Cobb angle were too diverse between patients with CP scoliosis or AIS. Eighteen patients were matched in each group according to the apex and Cobb angle (within 5-degree differences) of the major curve, and compared between matched groups (mCPscoliosis vs. mAIS). Results: In the comparison of the apex and Cobb angle-matched groups, there was no statistical difference in the Cobb angle between mCPscoliosis (80.7 +/- 13.8 degrees) and mAIS (78.6 +/- 13.6 degrees, p = 0.426), and the vertebral body rotation (25.4 +/- 15.4 degrees in mCPscoliosis vs. 24.4 +/- 6.5 degrees in mAIS, p = 0.594). There was no difference in the pedicle diameters of either the convex (3.6 +/- 1.1 mm in mCPscoliosis vs. 3.3 +/- 1.2 mm in mAIS, p = 0.24) or concave side (3.1 +/- 1.2 mm in mCPscoliosis vs. 2.7 +/- 1.6 mm in mAIS, p = 0.127). However, the patients in the mCPscoliosis group were younger (12.7 +/- 2.5 years vs. 14.6 +/- 2.4 years, p = 0.001), and the chord length was shorter on the convex (38.0 +/- 5.0 mm vs. 40.4 +/- 4.9 mm, p = 0.025) and concave (37.7 +/- 5.2 mm vs. 40.3 +/- 4.7 mm, p = 0.014) sides compared with those of the mAIS group. Conclusions: With a similar apex and Cobb angle, the vertebral body rotation and pedicle diameter in patients with CP scoliosis were comparable to those with AIS; however, the chord length was shorter in CP scoliosis. For the selection of the pedicle screw in CP scoliosis, the length of the pedicle screw should be more considered than the diameter.