Park Eugene J, Min Woo-Kie, Sim Seungbo
Kyungpook National University Hospital, 34986Kyungpook National University School of Medicine, Daegu, Republic of Korea.
Global Spine J. 2022 Jan;12(1):85-91. doi: 10.1177/2192568220947054. Epub 2020 Aug 26.
Retrospective radiological analysis.
Translaminar screw (TLS) placement is one of the fixation techniques in the subaxial cervical spine. However, it can be difficult to use in small diameter of the lamina. This study proposed a novel bicortical laminar screw (BLS) and analyzed the related parameters using computed tomography (CT).
Cervical CT images taken at our institution from January 2013 to March 2017 were used for measurement. On the axial images, the maximum screw length (MSL) and trajectory angle (TA) of BLS and TLS were measured, together with the distance from the midline (DM) to the BLS entry point and the lamina width (LW). On the parasagittal images, the height of the lamina (LH) was measured.
MSL of BLS and TLS were 21.00 and 20.97 mm, 19.02 and 20.91 mm, 18.45 and 21.01 mm, and 20.00 and 21.01 mm in C3, C4, C5, and C6, respectively. TA of the BLS and TLS were 21.24° and 34.90°, 19.05° and 34.22°, 18.65° and 33.61°, and 18.30° and 34.51° at C3, C4, C5, and C6, respectively. DM were 6.44, 5.77, 5.68, and 6.03 at C3, C4, C5, and C6, respectively. LW and LH were 3.52 and 12.44 mm, 2.87 and 12.49 mm, 2.76 and 12.42 mm, and 3.18 and 13.30 mm at C3, C4, C5, and C6, respectively.
We suggest that BLS fixation is a feasible alternative option for posterior fixation to the lamina of the subaxial cervical spine. It may be especially useful when pedicle screw, lateral mass screw, and TLS are not appropriate.
回顾性放射学分析。
经椎板螺钉（TLS）置入是下颈椎的固定技术之一。然而，在椎板直径较小时可能难以应用。本研究提出一种新型双皮质椎板螺钉（BLS），并使用计算机断层扫描（CT）分析相关参数。
使用2013年1月至2017年3月在本机构拍摄的颈椎CT图像进行测量。在轴位图像上，测量BLS和TLS的最大螺钉长度（MSL）和轨迹角度（TA），以及从中线（DM）到BLS进针点的距离和椎板宽度（LW）。在矢状旁位图像上，测量椎板高度（LH）。
C3、C4、C5和C6节段BLS的MSL分别为21.00和20.97mm、19.02和20.91mm、18.45和21.01mm、20.00和21.01mm。C3、C4、C5和C6节段BLS和TLS的TA分别为21.24°和34.90°、19.05°和34.22°、18.65°和33.61°、18.30°和34.51°。C3、C4、C5和C6节段的DM分别为6.44、5.77、5.68和6.03。C3、C4、C5和C6节段的LW和LH分别为3.52和12.44mm、2.87和12.49mm、2.76和12.42mm、3.18和13.30mm。
我们认为BLS固定是下颈椎椎板后路固定的一种可行替代方案。当椎弓根螺钉、侧块螺钉和TLS不合适时，它可能特别有用。
