Miller R M, Ebraheim N A, Xu R, Yeasting R A
Department of Orthopaedic Surgery, Medical College of Ohio, Toledo, USA.
Spine (Phila Pa 1976). 1996 Oct 15;21(20):2317-22. doi: 10.1097/00007632-199610150-00003.
This study compared the effectiveness of two transpedicular screw placement techniques: blind screw placement versus screw placement after direct determination of the superior, medial, and inferior borders of the pedicle through the opening of a "window" by the partial laminectomy and tapping technique.
To determine if the incidence and severity of pedicle violations resulting from transpedicular screw placement could be reduced by direct determination of the superior, medial, and inferior borders of the pedicle through the opening of a "window" by partial laminectomy.
Several studies regarding transpedicular screw fixation for unstable cervical spine injuries have been reported, but none has addressed the effectiveness in lowering the incidence of pedicle violation by opening a "window" by partial laminectomy for direct determination of the superior, medial, and inferior borders of the pedicle and using the tapping technique before and in planning for screw placement.
Eight adult cadaveric cervical spines (40 vertebrae from C3 to C7) were used for this study. Two groups were formed according to screw placement techniques. The first group was composed of 38 blinded transpedicular screw placements. The second group was composed of 40 screw placements using the partial laminectomy and tapping technique. After transpedicular screw placement, all specimens were evaluated radiographically and visually for violation of the pedicle.
A decrease in the incidence and severity of pedicle violation was seen in the second group with opening of the lamina and tapping technique compared with the blind screw placement group. However, the percentage of screws found to violate the pedicle with the opening of the lamina and tapping technique still was relatively high.
Transpedicular screw placement in the cervical spine is difficult, and a high percentage of violations of the pedicle wall occur. This technique should not be used routinely.
本研究比较了两种经椎弓根螺钉置入技术的有效性：盲法螺钉置入与通过部分椎板切除术打开“窗口”并采用攻丝技术直接确定椎弓根上、中、下边界后进行螺钉置入。
通过部分椎板切除术打开“窗口”直接确定椎弓根上、中、下边界，以确定是否能降低经椎弓根螺钉置入导致的椎弓根侵犯的发生率和严重程度。
关于不稳定型颈椎损伤经椎弓根螺钉固定的多项研究已见报道，但尚无研究探讨通过部分椎板切除术打开“窗口”直接确定椎弓根上、中、下边界并在螺钉置入前及规划时采用攻丝技术来降低椎弓根侵犯发生率的有效性。
本研究使用了8具成人尸体颈椎（C3至C7共40个椎体）。根据螺钉置入技术分为两组。第一组为38次盲法经椎弓根螺钉置入。第二组为40次采用部分椎板切除术和攻丝技术的螺钉置入。经椎弓根螺钉置入后，对所有标本进行影像学和肉眼评估以确定是否存在椎弓根侵犯。
与盲法螺钉置入组相比，采用椎板切开和攻丝技术的第二组椎弓根侵犯的发生率和严重程度有所降低。然而，采用椎板切开和攻丝技术时发现的椎弓根侵犯螺钉的百分比仍然相对较高。
颈椎经椎弓根螺钉置入困难，椎弓根壁侵犯的发生率较高。该技术不应常规使用。
