腰椎经皮椎弓钉皮质轨迹置入的影像解剖测量

An radiographically anatomical measurement of cortical bone trajectory for percutaneous lumbar pedicle screw placement

摘要:

[目的]测量中老年人腰椎经皮椎弓根皮质骨螺钉的解剖学参数并分析其经皮置钉可行性。[方法]选取 50 例中老年人腰椎三维 CT 资料并导入 Aquarius iNtuition Viewer V 4.4.6 软件，测量各节段皮质骨螺钉置钉横断面与矢状面的进钉角度、 安全范围、钉道直径及长度、螺钉轨迹皮肤进钉点至椎体上终板的距离和进钉点至棘突轴线的距离。[结果] L_1~5螺钉轨迹皮肤进钉点至椎体上终板的距离差异无统计学意义 (P＞0.05)，进钉点至棘突轴线的距离差异有统计学意义 (P＜0.05)。横断面上 L_1~5各节段的钉道直径逐渐增大，差异具有统计学意义 (P＜0.05)；各节段的钉道实际长度差异有统计学意义 (P＜0.05)，男性各节段钉道实际长度大于女性，差异有统计学意义 (P＜0.05)；腰椎各节段钉道理想外偏角较一致，差异无统计学意义 (P＞ 0.05)。矢状面上 L_1~5各节段钉道直径逐渐减小，差异具有统计学意义 (P＜0.05)，腰椎各节段钉道直径性别差异无统计学意义 (P＞0.05)。L_1~5 各节段钉道理想头倾角差异无统计学意义 (P＞0.05)，各节段钉道理想头倾角性别差异无统计学意义 (P＞ 0.05)。[结论] 通过至椎体上终板及至棘突中线的距离可找出经皮椎弓钉皮质轨迹螺钉的体表定位点，其在各节段间存在差异，该点可为中老年人腰椎经皮椎弓根皮质骨轨迹螺钉置入提供参考。

Abstract:

[Objective] To measure the anatomical parameters of cortical bone trajectory (CBT) for lumbar percutaneous pedicle corti- cal placement in middle-aged and elderly persons, and explore the feasibility of CBT percutaneous screw placement. [Methods] The threedimensional CT data obtained from 50 middle-aged and elderly persons were imported into Aquarius iNtuition Viewer V4.4.6 software. The screw insertion angle, safety range, diameter and length of the nail path, the distance between skin screw insertion point and vertebral upper endplate and the distance between screw insertion point and spinous process axis were measured. [Results] There was no significant differ- ence in the distance from the skin entry point to the vertebral upper endplate (P＞0.05) , whereas there was significant difference in the dis- tance from the skin entry point to the spinous process axis from L₁ to L₅ (P＜0.05) . In transvers plane, the diameters of the nail path gradual- ly increased from L₁ to L₅, which was statistically significant (P＜0.05) . The actual length of the nail path in different segments was of statis- tical significance (P＜0.05) , which in the male proved significantly greater than that in the female segments (P＜0.05) . The ideal external de- viation angles of the nail path in each segment of lumbar spine remained consistent, with no significant differences (P＞0.05) . In sagittal plane, the diameters of the nail path gradually decreased from L₁ to L₅, which was statistically significant (P＜0.05) , while no significant dif- ferences in the diameters of the nail path were found between two genders (P＞0.05) . The ideal cephalad inclination angle remained un- changed from L1 to L5 (P＞0.05) , and was not significantly different between the two genders (P＞0.05) . [Conclusion] From the upper end- plate of vertebral body to the midline of spinous process, a body surface positioning point for CBT percutaneous pedicle screw might be as- sured, which varies among different segments. This point can provide reference for the CBT percutaneous pedicle screw placement in mid- dle-aged and elderly people.