双平面骨科机器人系统辅助股骨颈骨折内固定的实验研究

Internal fixation of femoral neck fractures assisted by bi-planar navigation robot system： an experimental study

目的 通过股骨近端模型骨的模拟手术，与传统方法徒手操作的临床病例进行对比，评价改进后的双平面骨科机器人系统辅助股骨颈骨折空心钉导针置入位置的准确性以及螺钉的平行性。方法使用双平面骨科机器人系统对12根股骨近端模型骨进行辅助股骨颈空心钉置入的模拟手术，每例置入3枚导针，通过股骨颈截面的直接测量来评价机器人系统辅助操作的准确性；通过正、侧位X线片角度的测量和计算来评价机器人系统辅助下空心钉之间的平行性，与传统方法徒手操作的临床病例测算结果比较；同时比较两种操作方法所需的透视次数。结果 所有导针均一次成功置入，标本截面测量导针实际位置与规划位置相比误差范围在1mm左右；对平行度参数的统计学分析结果显示正、侧位X线片上机器人辅助操作的螺钉平行度均优于徒手操作（P〈0．05），稳定性也优于徒手操作（P〈0．05）；在透视次数上，机器人辅助操作组明显少于徒手操作组。结论 改进后的双平面骨科机器人系统可以有效地辅助完成股骨颈骨折空心钉内固定，导针位置的准确性能满足临床应用的需求。空心钉之间的平行性和操作的稳定性均明显优于传统的徒手操作，同时可以大大减少医患的放射线暴露时间。

Objective To assess accuracy of inserting the cannulated screw guide pin and parallelism of implanting the screws with the assistance of an improved bi-planar navigation robot system. Methods In 12 synthetic proximal femoral bones, insertion of cannulated hip screws was simulated under navigation of an improved bi-planar robot system. After every 3 guide pins were inserted in each case, the accuracy of insertion was evaluated by direct measurement of the transverse section of femoral neck, and the parallelism was accessed by calculating an index from the angles measured on the AP and lateral views of X-ray film. A statistical comparison was made with the conventional surgeries. The frequency of intraoperative fluoroscopy was also compared between the 2 operations. Results All guide pins were successfully inserted at one time. The measurement in the specimens revealed an error range of about 1 mm between the actual insertion site and the planned site. Statistical analysis of the screw parallelism index showed that the paral- lelism and operative stability in the computer-assisted navigation group were more satisfactory （ P 〈 0.05 ） than those in the conventional operation group. And the fluoroscopic frequency in the navigation group was also lower than that in the conventional operation group. Conclusion The improved bi-planar navigation robot system can effectively assist the fixation of the cannulated screws in the treatment of femoral neck fractures, because pin insertion can be more accurate, the parallelism of screws improved and the X-ray exposure reduced.