Defining the Iliac Wing Osseous Fixation Pathways: Anatomy and Implant Constriction Points

Computed tomography scans of 100 male and 100 female hemipelves were evaluated. The iliac wing was studied using manual best-fit analysis of the bounds of the inner and outer cortices. The IOTC was defined as the location of the iliac wing with
an intercortical width less than 5 mm. The shortest distance from the apex of the iliac crest to the superior border of the IOTC was defined as the iliac wing osseous corridor. Finally, the width of the gluteal pillar corridor from the gluteus medius tubercle to the ischial tuberosity was measured.

The IOTC is an elliptical area measuring 22.3 cm 2 . All ilia had an area where the inner and outer cortices converged to an intercortical width of less than 5 mm; 48% converged to a single cortex. The shortest mean distance from the superior edge of the iliac crest to the beginning of the IOTC was 20.3 mm in men and 13.8 mm in women (p<0.001). The gluteal pillar diameter averaged 5.3 mm in men and 4.3 mm in women (p<0.001).

A 4.5 mm iliac wing lag screw will not breach the cortex if it remains
within 20 mm or 14 mm distal to the cranial aspect of the iliac crest in males and females, respectively. Not only is the gluteal pillar smaller than previously thought, in some patients it may not be large enough for most implants. Overall, our findings provide improved understanding of the limits for implant use in the iliac wing as well as

对100名男性和100名女性的半骨盆的计算机断层扫描进行了评估。通过对内、外皮质边界的最佳拟合分析，研究了髂翼。髂翼间皮质宽度小于5毫米的位置被定义为髂翼间皮质（IOTC）。从髂嵴顶点到IOTC上缘的最短距离被定义为髂翼骨性通道。最后，从臀中肌结节到坐骨结节的宽度被测量为臀肌柱通道的宽度。IOTC为一个面积测量为22.3平方厘米的椭圆形区域。所有髂骨都存在内、外皮质交汇至间皮质宽度小于5毫米的区域；其中48%交汇为单一皮质。男性从髂嵴上缘到IOTC起始点的最短平均距离为20.3毫米，女性为13.8毫米（p<0.001）。臀肌柱直径在男性中平均为5.3毫米，在女性中为4.3毫米（p<0.001）。当髂翼螺钉长度为4.5毫米时，只要其位于髂嵴颅侧20毫米或女性14毫米以内，就不会穿透皮质。不仅臀肌柱的尺寸小于先前所认为的，在某些患者中，它可能不足以容纳大多数植入物。总体而言，我们的研究结果为髂翼植入物的使用提供了更深入的理解。