空心钉内固定股骨颈骨折的三维可视化虚拟手术研究

Three-dimensional visualized simulation of cannulated screw fixation for femoral neck fractures

目的 探讨计算机辅助虚拟手术设计在股骨颈骨折空心钉内固定术中的可行性及其临床应用价值.方法 2010年6月至12月共收治8例无移位或部分移位型股骨颈骨折患者,男2例,女6例；年龄24～58岁,平均43.4岁.利用Mimics 10.01软件对患者的CT扫描数据进行三维重建,在Solidworks 2010软件中建立不同型号螺钉零件库.利用Mimics10.01软件仿真模拟股骨颈骨折复位空心钉内固定术,进行术前虚拟手术设计,通过三维测量技术测量所需螺钉及其螺纹的长度、各螺钉之间及螺钉与股骨标志点之间的距离.术中根据测量的参数定位导针、选择合适型号螺钉,置入空心螺钉固定.术后根据X线片来对比虚拟计划与手术情况是否匹配. 结果 虚拟手术过程真实逼真,立体可视化效果好.虚拟手术设计与术中实际情况基本相符.8例患者从三维模型的建立至内固定完成所需时间平均为（1.5±0.2）h.24枚导针中有16枚为1次置入,X线片显示无一枚螺钉穿破骨皮质.24枚螺钉的长度与术前测量值均一致,上方靠近小转子侧导针实际位置与规划位置偏差范围平均为（1.35±0.50） mm,导针与股骨干的角度偏差范围平均为1.30°±0.65°.8例患者手术时间平均为（30.0±5.2）min,术中透视次数平均为35.5次. 结论 计算机辅助虚拟手术设计在股骨颈骨折空 心螺钉内固定术中是可行的,能更好地指导真实手术操作,减少术中透视次数.

Objective To explore the feasibility and clinical value of three-dimensional visualized simulation of cannulated screw fixation for femoral neck fractures. Methods Over the period from June through December 2010,8 patients with undisplaced or partially displaced femoral neck fracture were treated in our department.They were 2 men and 6 women,24 to 58 years of age （average,43.4 years）.Their CT scan data were used for three-dimensional reconstruction of their femoral neck fractures with software Mimics 10.01.Software Solidworks 2010 was used to construct models of different types of screw.Fracture reduction and fixation with cannulated screws were simulated with software Mimics 10.01 for preoperative design and three-dimensional measurement of necessary parameters related to the screwing.According to the parameters measured,suitable screws were chosen,position of the guide wire was determined and cannulated screws were inserted in the actual operation.The three-dimensional visualized simulation of cannulated screw fixation was evaluated according to the actual operation and postoperative X-rays. Results The virtual surgery appeared real with clear three-dimensional visualization.The simulated operative design was in good accordance with the actual operation.The mean time from construction of three-dimensional modals through completion of internal fixation was 1.5 ±0.2 hours for all patients.Of all the 24 guide wires,16 were successfully inserted at the first attempt.X-ray showed no penetration into the cortical bone by the screws.The lengths of the 24 screws were in complete agreement with the values measured preoperation.The average deviation between the actual and planned positions of the most lateral guide wire was 1.35 ±0.50 mm,and the average angular deviation between the guide wire and the femoral shaft was 1.30° ± 0.65°.The mean operation time was 30.0 ± 5.2 minutes for all patients and the mean radiation frequency was 35.5 times. Conclusion The three-dimensional visualized simulation of cannulated screw fixation is feasible for femoral neck fractures because it can provide better aids to the actual operation and reduce intraoperative radiations.