计算机辅助下经髋臼长螺钉钉道参数的研究  

A computer-aided system for longer transacetabular screw trajectory research

作　　者：吴浩波[1] 蔡春元[2] 季康[1] 余世策[3] 严世贵[1] 

机构地区：[1]浙江大学医学院附属第二医院骨科,杭州310009 [2]温州医学院附属第三医院 [3]浙江大学建工学院实验中心

出　　处：《中华骨科杂志》2010年第4期411-416,共6页Chinese Journal of Orthopaedics

摘　　要：目的基于骨盆的解剖结构，提出一种经髋臼长螺钉的固定方法，并测算钉道进钉区位置和进钉的方向角度。方法使用20例成年男性半骨盆的CT数据，使用三维建模技术对半骨盆骨骼进行重建和分区，每半骨盆分成髂后区、髂前区、耻骨区和坐骨区，并对每一分区进行平行截骨获得每层断层轮廓数据；通过断层轮廓控制有效钉道的范围，并使用计算辅助程序对有效钉道的进钉点在髋臼上的位置进行测算，再对经过每个有效进钉点的所有有效钉道进行再次优化选择，最后获得相对应的最佳钉道的方向，最后将进钉区域和角度以拓扑地形图的格式显示。结果计算结果显示半骨盆的解剖结构允许经髋臼螺钉进行加长应用，经髋臼长螺钉进钉区的范围大小依次是髂后区、髂前区、耻骨区和坐骨区，其中髂后和髂前区进钉区有部分重叠，坐骨区进钉长度无法到达坐骨支远1／3部。结论在解剖上，改变经髋臼螺钉的植入方向，可以在骨盆的各个分区内获得加长螺钉的固定。Objective To overcome the inherent limitations of traditional technique, we promoted that long transacetabular screws could be safely implanted into ilium, pubis and ischium. Methods Twenty 3D hemi-pelvis models were constructed using CT data, and each was divided into four parts： posterior ilium, anterior ilium, pubis and ischium. Each part was undertaken parallel osteotomy and the contour coordinates of each section were recorded. The acetabular cup in each model was defined as a hemisphere with 52 mm diameter. An uniform lattice at equal intervals of 2° in longitude-latitude on the acetabular cup were regarded as entry points. A computer aided program was developed to simulate screw trajectories in all directions through every entry point, then select out all the useful entry points and corresponding trajectories. Then the optimum direction of screw trajectory of each entry point was also calculated. Topographic maps of entry zone were delineated in the acetabular quadrant system to present the results. Results According the bone anatomy, the posterior ilium was the most favorable area for the implantation of long screws, secondly the anterior ilium, thirdly the pubis and minimally the ischium. The entry zone in posterior ilium has the longitude from -148.0° to 29.2°, latitude from 7.5° to 87.3°, and ct angle for trajectory direction was from -85.3° to - 53.8°,13 angle from 46.3° to 60.2°. In anterior ilium has the longitude from -29.0° to 31.4°, latitude from 7.6° to 54.2°, and α angle was from -36.2° to -49.8°, 13 angle from 19.7° to 33.8°. In pubis has the longitude from 56.4° to 100.6°, latitude from 6.8° to 23.2°, and α angle was from 91.3° to 117.2°, 13 angle from 10.5° to 17.9°. And the anatomy of ischium was not permitted transacetabular screws to reach the distant 1/3 part of the ischium ramus. Conclusion The long transacetabular screws were permitted to deeper insertion when the trajectories were not perpendicular to the cup wall. The computer-aided system developed in th

关 键 词：髋臼 体层摄影术 X线计算机 骨螺丝 

分 类 号：R687.3[医药卫生—骨科学]