【摘要】 目的　通过解剖学研究和影像学手段 ,了解下颈椎侧块螺钉固定与椎动脉之间的关系以及斜位片在置钉过程中对神经根的监测价值。方法　 (1)取 2 8具尸体的C3 ～C7标本 ,年龄 2 8～ 79岁。摄取标本各椎体的横断面片 ,测量X线片上C3 ～C7横突孔外缘与侧块背面中心内侧 1mm处的连线在横断面上与矢状轴之间的成角。 (2 )取 10具标本 ,以侧块背面中心点内侧 1mm处为入针点、横突与侧块相交处为出针点在C3 ～C6侧块内置入克氏针。当针尖未超出或超出侧块远侧皮质 2、4、6mm时 ,摄取标本左右 4 5°斜位片。把斜位片上椎间孔分为上、下两部分 ,上部实际是真正的椎间孔 ,下部则相当于横突间孔位置。观察针尖在斜位片上椎间孔内的位置并计数 ,同时与实际解剖比较两者的一致性。　结果　 (1)C3 ～C6横突孔外缘与侧块背面中心内侧 1mm处的连线在横断面上与矢状轴成外偏 5°～ 12°的角度 ,椎体间差别无统计学意义 (P >0 0 5 )。 (2 )以横突与关节突相交处为出针点 ,实际观察当针尖超出侧块远侧皮质 2mm时 ,未突入横突间孔 ;当超出距离为 4、6mm时 ,针尖则突入横突间孔。X片上显示当针尖未超出远侧皮质时 ,斜位片上有 15 %针尖出现于椎间孔下部 ;当针尖超出 2mm时 ,斜位片 4 1 3%针尖出现于椎间孔下部 ;当针尖超出 4mm更多还原

【Abstract】 Objective To determine the location of the vertebral artery foramens from C 3 to C 6 and their relationship to the point 1 mm medial to the center of the lateral mass and to identify the value of oblique radiograph for cervical lateral mass screw trajectory by a cadaveric study. Methods (1)Twenty eight cervical specimens (C 3 C 7) of human cadavers aged from 28 to 79 years were analysed. The transverse radiographs of C 3 C 6 vertebrae were taken and the angle between the parasagittal plane and the line connecting the point of the lateral mass with the lateral limit of the transverse process foramen of C 3 C 6 were measured.(2)The K wires were drilled into lateral mass of C 3 C 6 starting 1mm medial to the center of the lateral mass and exiting by the juncture between the transverse process and the facet in ten specimens. Four wire placements under direct visualization, including placement of the wire tip staying the ventral cortex and 2, 4, 6 mm overpenetration of the ventral cortex of lateral mass, were performed separately on each specimen. After each placement, radiographs were taken on 45°oblique left and 45°oblique right views. Each intervertebral foramen on the oblique radiographs was divided into two parts: superior and inferior parts. The former is the true intervertebral foramen, while the latter is the intertransverse foramen on the gross specimen. The number of wire tips in each part was quantified for each placement. All results on the radiographs were compared with those on the gross anatomy. Results (1) The angles between the parasagittal plane and the line connecting the posterior starting point of the lateral mass with the lateral limit of the transverse foramen (C 3 C 6) were lateral to the sagittal plane, ranging from 5° to 12 °. Among the vertebrae, there were no statistically significant difference ( P >0 05). (2) 15% of the wires without overpenetration and 41 3% with 2 mm overpenetration were found in the inferior parts of the intervertebral foramen in oblique views, while the wires were not noted in the intervertebral foramen by gross anatomy. with 4 mm overpenetration of the ventral cortex, 35% and 65% of wires were noted in the superior and inferior parts of the intervertebral foramen respectively, while only 28 8% of wires were found in the inferior part approximating the nerve roots in gross specimens. With 6 mm overpenetration, the number in the intervertebral foramen were 63 8% superiorly and 36 2% inferiorly on the oblique radiographs while all the tips were at the inferior part (intertransverse foramens) in gross specimens. The tip of wire crossed the line connecting the posterior borders of the intervertebral foramens in oblique radiographs when it penetrated the ventral cortex of lateral mass 4 mm or more. Conclusions (1) There is no risk of damaging the vertebral artery if a screw is directed more than 15° lateral to the sagittal plane at C 3～6 starting 1 mm medial to the center of the lateral mass. (2) Ideal screw tip position on oblique radiograph may not cross the line connecting the posterior borders of the intervertebral foramen on radiograph. If the screw tip is noted in the superior part of intervertebral foramen on the oblique radiograph, the screw may be identified as dangerous.更多还原