骨盆髂嵴外固定架Schanz钉置钉区域的影像学研究

目的:对骨盆髂嵴外固定架Schanz钉置钉区域进行影像学研究以指导置钉.方法:将筛选出的9例成人正常骨盆的2.0 mm层厚轴向CT扫描结果导入MIMICS 10.0软件.通过后者将髂嵴外固定架Schanz钉置钉区域,即位于髂前上棘及臀中肌结节之间的、髋臼之上的髋臼前柱的高位部分,进行真正矢状面及冠状面重建.然后应用该软件的测量工具于重建面上进行测量,最后对测量结果进行分析.结果:位于髂前上棘前缘后方16.5 mm宽度为49.6 mm的髂嵴节段可用作定位髂嵴外固定架Schanz钉的进钉点.该节段髂嵴所覆盖骨质相对丰厚及纵深,可完全容纳直径为5.0 mm的Schanz钉,并可经髂嵴将该直径的螺钉最浅打入71.7 mm至髋臼顶及最深打入143.5 mm至髋臼后方相对致密的骨质.结论:本研究结果可用于指导髂嵴外固定Schanz钉的置入,于上述进钉点区域将Schanz钉朝向髋臼或其后方打入臼顶或臼后相对致密的骨质以获得较好的把持力从而增强固定效果.

Radiographic analysis of the osseous fixation zone for the iliac crest external fixation with Schanz screws

Objective: To radiographically analyze the osseous fixation zone for the iliac crest external fixation with Schanz screws and in order to guide their placement.Methods: Nine adults with 2.0-mm-slice continuous pelvic axial CT scans were selected as research subjects. Each CT scan data was imported into MIMICS 10.0. The osseous fixation zone--the upper portion of the anterior column of the acetabulum which is located between the anterior superior iliac spine and the gluteal medius pillar and between the iliac crest and the acetabulum-for the iliac crest external fixation with Schanz screws was reconstructed into true sagittal and true coronal planes by using the software. Then the measurements were taken on the reconstructed planes with measuring tools. Finally,the measured data was analyzed.Results: The palpable iliac crest segment,which was of 49.6 mm width and located 16.5 mm posterior to the anterior superior iliac spine could be used to locate the start points of the Schanz screws. Under the above-mentioned iliac crest segment,the osseous zone was deep,got ample bony materials and could intraosseously contain Schanz screws with 5.0 mm diameter. The screws could be safely inserted to a minimal depth of 71.7 mm towards the acetabular dome and to a maximal depth of 143.5 mm posterior to the acetabulum.Conclusion: The study can guide the effective insertion of the iliac crest Schanz screws. By setting a suitable start point in the above-mentioned iliac crest region and angling correctly relative to the acetabulum,the Schanz screw can be inserted into the relative strong cancellous bone above or posterior to the acetabulum with a considerable depth,to getting more bone engagement.