Chen Hongfen, Wang Gang, Li Runguang, Sun Yongjian, Wang Fuming, Zhao Hui, Zhang Peijun, Zhang Xuanxuan
Department of Orthopaedics and Traumatology, The Fifth Affiliated Hospital of Southern Medical University, GuangZhou, China.
Department of Orthopaedics and Traumatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, People's Republic of China.
Int Orthop. 2016 Apr;40(4):827-34. doi: 10.1007/s00264-015-2813-8. Epub 2015 Jun 27.
To test whether a novel guide template we designed can facilitate accurate insertion of antegrade lag screws in the fixation of acetabular posterior column fractures.
We created virtual three-dimensional reconstruction models of the pelvis from CT scan data obtained from 96 adult patients without any bony problems. A virtual cylindrical implant was placed along the longitudinal axis of the acetabular posterior column passing through the ischial tuberosity. The diameter of cylindrical implant was augmented to 6.5 mm, and the direction was adjusted until the optimal screw path was found using the reverse engineering technique. The orifice of this cylinder from the iliac fossa was determined as the entry point for the antegrade lag screw. The anatomical parameters of the screw entry path were measured and saved in .stl format. The guide template was designed according to the acetabular morphology and the measured anatomical parameters before it was put into manufacture of a solid template with the rapid prototyping technique. The feasibility and accuracy of the guide template were tested in cadaveric pelvises. Finally, the guide template was used in real surgery for five patients. Furthermore, the time required for surgery was recorded.
Under the guide of this navigation template, antegrade lag screws were successfully placed in the posterior column of the acetabulum in the cadaveric test. And five lag screws were successfully placed in five patients. The mean time of antegrade lag screw insertion required 5.8 (3-10) min.
Antegrade lag screws can be more accurately put into the posterior column of the acetabulum with the help of this navigation template.
测试我们设计的一种新型导向模板能否促进在髋臼后柱骨折固定中准确置入顺行拉力螺钉。
我们从96例无任何骨质问题的成年患者的CT扫描数据创建骨盆的虚拟三维重建模型。沿着髋臼后柱的纵轴并穿过坐骨结节放置一个虚拟圆柱形植入物。将圆柱形植入物的直径增大到6.5毫米，并调整方向，直到使用逆向工程技术找到最佳螺钉路径。将该圆柱体从髂窝处的开口确定为顺行拉力螺钉的入点。测量螺钉入路的解剖参数并以.stl格式保存。根据髋臼形态和测量的解剖参数设计导向模板，然后使用快速成型技术将其制作为实体模板。在尸体骨盆中测试导向模板的可行性和准确性。最后，该导向模板用于5例患者的实际手术中。此外，记录手术所需时间。
在该导航模板的引导下，在尸体测试中顺行拉力螺钉成功置入髋臼后柱。5例患者的5枚拉力螺钉均成功置入。顺行拉力螺钉置入的平均时间为5.8（3 - 10）分钟。
借助该导航模板，顺行拉力螺钉能够更准确地置入髋臼后柱。
