Ghobrial George M, Al-Saiegh Fadi, Franco Daniel, Heller Joshua
*Department of Neurological Surgery, Thomas Jefferson University Hospital †Neurological Surgery, Division of Spine and Peripheral Nerve, Thomas Jefferson University Hospital, Philadelphia, PA.
Clin Spine Surg. 2017 May;30(4):150-155. doi: 10.1097/BSD.0000000000000481.
Minimally invasive surgical techniques may decrease length of stay, operative duration and blood loss, and postoperative pain. Numerous technical challenges and concerns surround the placement of percutaneous pedicle screws at the lumbosacral level. Maximization of screw triangulation, bicortical purchase, and rostral bias toward the sacral promontory has been shown repeatedly to stabilize lumbosacral segment instrumentation and maximize pullout strength. Because of the unique anatomy, conventional anteroposterior (AP) and lateral radiographic views are relatively less reliable at determining screw depth and penetration of the sacral cortex. Percutaneous sacral pedicle fixation using AP and lateral 2-dimensional fluoroscopy is complicated by the variable contour of the sacral alae and promontory. The pelvic inlet view is ideal for visualization of the ventral screw extent and is obtained by directing 45-degree cephalad and 0-degree mediolateral, with adjustments aligning the patient's pelvic brim. The modified pelvic outlet view is obtained with the trajectory axis being directed 45-degree caudal from the AP plane. This aligns the pubic symphysis with the second sacral vertebrae providing visualization of the superior boundary of the S1-bony neural foramen and any inferior wall pedicle breaches. The authors describe this reliable fluoroscopic technique and their clinical experience with percutaneous S1-screw placement.
微创外科技术可能会缩短住院时间、手术时长和失血量，并减轻术后疼痛。在腰骶部置入经皮椎弓根螺钉存在诸多技术挑战和问题。反复研究表明，最大化螺钉三角定位、双侧皮质固定以及向骶骨岬的头侧偏斜可稳定腰骶段器械固定并最大化拔出强度。由于解剖结构独特，传统的前后位（AP）和侧位X线片在确定螺钉深度和骶骨皮质穿透情况时相对不太可靠。使用AP和侧位二维荧光透视进行经皮骶椎弓根固定会因骶骨翼和岬部的轮廓变化而变得复杂。骨盆入口位对于观察腹侧螺钉的长度很理想，通过将射线向头侧倾斜45度、向内侧倾斜0度并调整以对准患者的骨盆边缘来获得。改良的骨盆出口位是通过将轨迹轴从AP平面向尾侧倾斜45度获得的。这使耻骨联合与第二骶椎对齐，从而可以观察S1骨性神经孔的上边界以及任何下壁椎弓根破裂情况。作者描述了这种可靠的荧光透视技术以及他们经皮置入S1螺钉的临床经验。
