Pai Balaji S, Nirmala S, Muralimohan S, Varsha S M
Department of Neurosurgery and Anatomy, M. S. Ramaiah Medical College, Bangalore, India.
Neurol India. 2010 Mar-Apr;58(2):253-8. doi: 10.4103/0028-3886.63808.
Knowledge of the morphometric anatomy of the pedicles in thoracic spine is essential for the surgeon attempting thoracic pedicle screw placement.
To study the morphometry of the pedicles in the thoracic spine in Indian subjects and note the anatomical landmarks required for safe and accurate pedicle screw placement.
An anatomico-radiological study with cadaveric confirmation was conducted in a medical college and tertiary care center.
Morphometric anatomy of 720 pedicles from T1-T12 was studied. The study consisted of 15 separated thoracic vertebral cadavers and 15 computed tomographic scans of undiseased thoracic spine. Transverse and sagittal pedicle diameters, transverse pedicle angle, chord length and the pedicle entry point landmarks were studied. Using the results, accuracy of the pedicle screw placement was confirmed in 120 pedicles from five unseparated cadavers.
Transverse pedicle diameter was narrowest at T4 and gradually increased craniocaudally. Twenty-two percent of the pedicles from T4 to T6 were less than 4.5 mm, but none were less than 3.5 mm. The transverse pedicle angle was widest at T1 (26.50) and decreased caudally to T12 (8.10). The chord length gradually increased caudally from a minimum of 30.4 mm at T1 to a maximum of 43.3 mm at T12. Landmarks (transverse and vertical distance) for the pedicle entry point were measured from the reference point taken as the center of the junction of lamina and the transverse process. The pedicle entry point was always superolateral to this reference point.
Knowledge of the pedicle diameter and chord length is essential for choosing the appropriate pedicle screw, whereas the pedicle angle and the entry point are important for accurate screw placement.
对于尝试进行胸椎椎弓根螺钉置入的外科医生而言，了解胸椎椎弓根的形态测量解剖学知识至关重要。
研究印度受试者胸椎椎弓根的形态测量学，并记录安全准确置入椎弓根螺钉所需的解剖标志。
在一所医学院和三级医疗中心进行了一项有尸体验证的解剖放射学研究。
对T1 - T12的720个椎弓根的形态测量解剖学进行了研究。该研究包括来自15具分离的胸椎尸体以及15例无病变胸椎的计算机断层扫描。研究了椎弓根的横径和矢状径、横椎弓根角、弦长以及椎弓根进针点标志。利用这些结果，在来自5具未分离尸体的120个椎弓根中确认了椎弓根螺钉置入的准确性。
横椎弓根直径在T4处最窄，并向头尾方向逐渐增大。T4至T6的椎弓根中有22%小于4.5毫米，但无一小于3.5毫米。横椎弓根角在T1处最宽（26.5°），向尾侧至T12逐渐减小（8.1°）。弦长从T1处的最小值30.4毫米向尾侧逐渐增加至T12处的最大值43.3毫米。椎弓根进针点的标志（横向和垂直距离）是从以椎板与横突交界处中心为参考点进行测量的。椎弓根进针点始终位于该参考点的外上侧。
了解椎弓根直径和弦长对于选择合适的椎弓根螺钉至关重要，而椎弓根角度和进针点对于准确的螺钉置入很重要。
