Karatas Derya, Dagtekin Ahmet, Uygur Saygi, Barut Irmak Tekeli, Kara Engin, Esen Kaan, Avci Emel, Baskaya Mustafa Kemal
Department of Neurosurgery, Mersin University Faculty of Medicine, Mersin, Türkiye.
Department of Neurosurgery, Kadirli State Hospital, Osmaniye, Türkiye.
Surg Radiol Anat. 2025 Apr 3;47(1):112. doi: 10.1007/s00276-025-03599-8.
The aim of the present study is to analyze the feasibility of a new optimized C1 lateral mass and C2 pedicle screw method that has a suitable trajectory for a range of anatomical variations to decrease the risk of vertebral artery injury.
The craniovertebral junction of 17 cadavers (34 sides) were dissected after performing thin-cut computed tomography. The screw entry points, targets, angles, and lengths of the trajectories were performed for C1 lateral mass and C2 pedicle. We particularly focused on the morphometric features and the safety of trajectories in cadavers with vascular and bony variations.
For the C1 lateral mass, the ideal medial and cranial angles were 13.4° ± 1.0° and 14.7° ± 1.1°, respectively. For the C2 pedicle screw, the cranial and medial angles were 27.7° ± 1.4° and 20.4° ± 1.5°, respectively. High-riding vertebral arteries (HRVA) were observed in 35.3% of all cadavers. The incidence of an arcuate foramen was 47% among all sides and its coexistence with an HRVA among all cadavers was 23.5%.
Preoperative pedicle-oriented radiological evaluation is crucial before C1 lateral mass and C2 pedicle screw placement because of the high incidence of bony and vascular variations. Using our safe C2 pedicle trajectory, a longer and safer screw course that preserves the vertebral artery can be achieved with a more feasible cranial angle, even with HRVAs, with the exception of narrow pedicle anatomy.
本研究旨在分析一种新的优化的C1侧块和C2椎弓根螺钉方法的可行性，该方法具有适合一系列解剖变异的轨迹，以降低椎动脉损伤的风险。
对17具尸体（34侧）的颅颈交界区进行薄层计算机断层扫描后进行解剖。对C1侧块和C2椎弓根的螺钉进针点、靶点、角度和轨迹长度进行测量。我们特别关注了存在血管和骨骼变异的尸体的形态学特征和轨迹安全性。
对于C1侧块，理想的内侧角和颅侧角分别为13.4°±1.0°和14.7°±1.1°。对于C2椎弓根螺钉，颅侧角和内侧角分别为27.7°±1.4°和20.4°±1.5°。在所有尸体中，35.3%观察到高位椎动脉（HRVA）。所有侧别中，弓状孔的发生率为47%，其与HRVA在所有尸体中的共存率为23.5%。
由于骨骼和血管变异的发生率较高，在进行C1侧块和C2椎弓根螺钉置入之前，术前以椎弓根为导向的影像学评估至关重要。使用我们安全的C2椎弓根轨迹，即使存在HRVA，除了椎弓根解剖结构狭窄的情况外，也可以通过更可行的颅侧角实现更长、更安全的保留椎动脉的螺钉置入路径。
