Suresh Dineshwary, Naidoo Nerissa, AlSharhan Rashid, Al Bastaki Usama, Lakshmanan Jeyaseelan, Joseph Baylis Vivek, Prithishkumar Ivan James
College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Health, Dubai, UAE.
Director of Diagnostic Imaging, Rashid Hospital, Dubai Health, Dubai, UAE.
Sci Rep. 2025 Jan 15;15(1):1992. doi: 10.1038/s41598-025-85181-1.
The first cervical vertebra (C1) is atypical in shape and bears a complex relationship with important neurovascular structures such as the vertebral artery and cervical spinal cord which are at risk of injury during misplaced screw fixation of C1. Placement of screws into the lateral mass of C1 vertebra is performed for stabilization of the craniovertebral junction. The objective of this study was to describe ideal screw dimensions, precise entry points, safe bony corridors, and ideal trajectories for placement of lateral mass screws in the Emirati population. CT scans of 160 Emirati patients (> 18 years) were studied and variables relevant to lateral mass screw fixation were measured. Screw entry at the centre of lateral mass, below its junction with the posterior arch, allowed straight screws of lengths of 20 mm and 19.5 mm in Emirati males and females, respectively. A medial angulation of 20° in males and 15° in females allowed maximum bone purchase. Screw entry at the junction of medial margin of posterior arch and lateral mass allowed straight screws of length 18 mm in both males and females. We recommend safe cephalic angulations of 19° and 16°in males and females, respectively. The mean critical width was 7.6 mm in males and 6.8 mm in females which would safely permit screws of width 4.0 mm. Pre-operative knowledge of the above dimensions would help in greater precision, minimizing the risk of injury to neurovascular structures in the vicinity of C1 lateral mass.
第一颈椎（C1）形状不规则，与椎动脉和颈脊髓等重要神经血管结构关系复杂，在C1螺钉固定位置不当时有受伤风险。将螺钉置入C1椎体侧块是为了稳定颅颈交界区。本研究的目的是描述阿联酋人群中侧块螺钉置入的理想螺钉尺寸、精确进针点、安全骨通道和理想轨迹。对160例年龄大于18岁的阿联酋患者的CT扫描进行研究，并测量与侧块螺钉固定相关的变量。在侧块中心、与后弓交界处下方进针，阿联酋男性和女性分别可使用长度为20mm和19.5mm的直螺钉。男性内倾角20°、女性内倾角15°可实现最大骨质把持。在后弓内侧缘与侧块交界处进针，男性和女性均可使用长度为18mm的直螺钉。我们建议男性和女性的安全头倾角分别为19°和16°。男性的平均临界宽度为7.6mm，女性为6.8mm，可安全容纳宽度为4.0mm的螺钉。术前了解上述尺寸将有助于提高精度，将C1侧块附近神经血管结构的损伤风险降至最低。
