[C2椎弓根螺钉固定的进钉点及植入技术的解剖学研究]

Tang Xiaojun, Cao Qi, Chen Liangyuan, Tang Guojun, Yang Wuzhou, Li Yanbing

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2015 Feb;29(2):175-8.

OBJECTIVE

To determine the entry point and screw implant technique in posterior pedicle screw fixation by anatomical measurement of adult dry samples of the axis so as to provide a accurate anatomic foundation for clinical application.

METHODS

A total of 60 dry adult axis specimens were selected for pedicle screws fixation. The entry point was 1-2 mm lateral to the crossing point of two lines: a vertical line through the midpoint of distance from the junction of pedicle medial and lateral border to lateral mass, and a horizontal line through the junction between the lateral border of inferior articular process and the posterior branch of transverse process. The pedicle screw was inserted at the entry point. The measurement of the anatomic parameters included the height and width of pedicle, the maximum length of the screw path, the minimum distance from screw path to spinal canal and transverse foramen, and the angle of pedicle screw. The data above were provided to determine the surgical feasibility and screw safety.

RESULTS

The width of upper, middle, and lower parts of the pedicle was (7.35 ± 0.89), (5.50 ± 1.48), and (3.97 ± 1.01) mm respectively. The pedicle height was (9.94 ± 1.16) mm and maximum length of the screw path was (25.91 ± 1.15) mm. The angle between pedicle screw and coronal plane was (26.95 ± 1.88) degrees and the angle between pedicle screw and transverse plane was (22.81 ± 1.61) degrees. The minimum distance from screw path to spinal canal and transverse foramen was (2.72 ± 0.83) mm and (1.98 ± 0.26) mm respectively.

CONCLUSION

According to the anatomic research, a safe entry point for C2 pedicle screw fixation is determined according to the midpoint of distance from the junction of pedicle medial and lateral border to lateral mass, as well as the junction between the lateral border of inferior articular process and the posterior branch of transverse process, which is confirmed to be effectively and safely performed using the entry point and screw angle of the present study.

目的

通过对成人枢椎干燥标本进行解剖测量，确定枢椎后路椎弓根螺钉固定的进钉点及螺钉植入技术，为临床应用提供准确的解剖学依据。

方法

选取60例成人枢椎干燥标本进行椎弓根螺钉固定。进钉点位于两条线交点外侧1-2mm处：一条垂直线经过椎弓根内侧与外侧缘交界处至侧块距离的中点，另一条水平线经过下关节突外侧缘与横突后支的交界处。在进钉点处插入椎弓根螺钉。解剖参数测量包括椎弓根的高度和宽度、螺钉通道的最大长度、螺钉通道至椎管和横突孔的最小距离以及椎弓根螺钉的角度。提供上述数据以确定手术的可行性和螺钉的安全性。

结果

椎弓根上、中、下部分的宽度分别为(7.35±0.89)、(5.50±1.48)和(3.97±1.01)mm。椎弓根高度为(9.94±1.16)mm，螺钉通道的最大长度为(25.91±1.15)mm。椎弓根螺钉与冠状面的夹角为(26.95±1.88)度，与横断面的夹角为(22.81±1.61)度。螺钉通道至椎管和横突孔的最小距离分别为(2.72±0.83)mm和(1.98±0.26)mm。