中上颈椎侧块与寰椎椎弓根位置关系的解剖研究

目的研究中上颈椎侧块与寰椎椎弓根的位置关系,建立以中上颈椎侧块为解剖标志的寰椎椎弓根螺钉进钉点定位技术。方法20具尸体标本,分别测量寰椎椎弓根和中上颈椎侧块的内缘、中点、外缘与正中矢状面的垂直距离,通过分析测量值间的关系,建立寰椎椎弓根螺钉进钉定位技术。结果C2-4侧块的内缘分别在寰椎椎弓根内缘外侧0．37mm、0．27mm、0．24mm处;C2-4侧块的中点分别在寰椎椎弓根中点外侧1．18mm、1．41mm、1．74mm处;C2-4侧块的外缘分别在寰椎椎弓根外缘外侧1．96mm、2．54mm、3．24mm处。结论中上颈椎侧块与寰椎椎弓根间存在较恒定的解剖位置关系,C3和C4侧块与枢椎侧块一样,可作为术中确定寰椎后弓显露范围和判断寰椎椎弓根螺钉进钉点的解剖学标志。

Anatomic identification of the location of the pedicle of atlas with the lateral mass of C2 to C4 as the landmark

Objective To study the relevant position of the pedicle of C_1 to the lateral mass of C_(2-4), set up an identification technique for the entry point decision of C_1 pedicle screw by using the lateral mass of C_(2-4) as anatomic landmarks. Methods Twenty cadaver specimens were used to measure the distance from the saggital midline of spine to the medial border, the midpoint and the lateral border of C_1 pedicle or the lateral mass of C_2, C_3 or C_4. The anatomic relation between the measurements data of C_1 pedicle and that of the lateral masses of the cervical vertebrae were analyzed, and the technique of C_1 pedicle screw fixation was established. Results The average medial border of the lateral mass of C_2, C_3 and C_4 was 0.37 mm, 0.27 mm and 0.24 mm lateral to that of C_1 pedicle, the average midpoint of the lateral mass of C_2, C_3 and C_4 was 1.18 mm, 1.41 mm and 1.74 mm lateral to that of C_1 pedicle, and the average lateral border of the lateral mass of C_2, C_3 and C_4 was 1.96 mm, 2.54 mm and 3.24 mm lateral to that of C_1 pedicle, respectively. Conclusion There is a steady anatomic location relation between C_1 pedicle and the lateral mass of C_2, C_3 or C_4. As well as the lateral mass of C_2, the lateral mass of C_3 or that of C_4 could be convenient anatomic landmarks to determine the location of C_1 pedicle and the position of C_1 pedicle screw entry point.