Orchowski Joseph R, Polly David W, Kuklo Timothy R, Klemme William R, Schroeder Teresa M
Walter Reed Army Medical Center, Department of Orthopaedic Surgery and Rehabilitation, Washington, DC, USA.
Am J Orthop (Belle Mead NJ). 2006 Mar;35(3):144-6.
Iliac screw fixation is often used for long fusions to the sacropelvis. Maximum iliac screw purchase is obtained both by placing the screws within 1.5 cm of the greater sciatic notch and by extending them anterior to the axis of rotation in flexion-extension. Screw insertion is "blinded" or dependent on tactile feedback, and hence extreme care is necessary to avoid incorrect placement and damage to vital neurovascular structures in the pelvis and sciatic notch. Long screws may violate the hip joint while medial placement may injure the lumbosacral plexus and the nearby vessels. To explore the best intraoperative fluoroscopic method of determining optimal iliac screw placement, we used a synthetic pelvis model to investigate screw placement conditions: (1) optimal anatomic placement, (2) violation of the sciatic notch, (3) hip joint violation, (4) medial wall violation, and (5) lateral wall violation. Each condition was examined utilizing fluoroscopy with posteroanterior, inlet, outlet, lateral, iliac oblique, and obturator oblique Judet views to simulate operative conditions. These views were obtained to evaluate critical malposition of iliac screws. We found that, for a sciatic notch violation, the obturator oblique view best demonstrated the cortical breech, while for a hip joint violation, the inlet and outlet views were best. For a medial wall violation, the iliac oblique view best showed the violation. For a lateral wall violation, we were unable to demonstrate the cortical breech using these fluoroscopic views. Fluoroscopy is an effective method to determine sciatic notch, hip joint, and medial wall violations after iliac screw placement; however, it is not effective in identifying a lateral wall violation.
髂骨螺钉固定常用于骶骨盆的长节段融合。通过将螺钉置于坐骨大切迹1.5厘米范围内并使其在屈伸时延伸至旋转轴前方，可实现最大程度的髂骨螺钉置入。螺钉插入是“盲目”的或依赖触觉反馈，因此必须格外小心，以避免错误放置并损伤骨盆和坐骨切迹内的重要神经血管结构。长螺钉可能会侵犯髋关节，而向内侧放置可能会损伤腰骶丛和附近血管。为了探索确定最佳髂骨螺钉置入位置的最佳术中透视方法，我们使用合成骨盆模型研究螺钉置入情况：（1）最佳解剖位置，（2）侵犯坐骨切迹，（3）侵犯髋关节，（4）侵犯内侧壁，以及（5）侵犯外侧壁。利用透视检查每种情况，采用前后位、入口位、出口位、侧位、髂骨斜位和闭孔斜位Judet视图来模拟手术情况。获取这些视图以评估髂骨螺钉的严重位置不当。我们发现，对于侵犯坐骨切迹的情况，闭孔斜位视图最能显示皮质突破，而对于侵犯髋关节的情况，入口位和出口位视图最佳。对于侵犯内侧壁的情况，髂骨斜位视图最能显示侵犯情况。对于侵犯外侧壁的情况，我们无法通过这些透视视图显示皮质突破。透视检查是确定髂骨螺钉置入后坐骨切迹、髋关节和内侧壁侵犯情况的有效方法；然而，它在识别外侧壁侵犯方面并不有效。
