枕下远外侧经髁入路的显微解剖学研究

Microanatomic study of suboccipital transcondylar approach

目的通过在手术显微镜下对尸头的解剖研究,为枕下远外侧经髁入路提供应用解剖学基础。方法对15例成人汉族尸头湿标本进行解剖学研究,按肌肉群、硬膜外、硬膜内进行描述和测量。结果枕下三角由头直肌、上斜肌、下斜肌组成,内含椎动脉和C1神经,椎动脉被一层丰富的椎静脉丛包绕,呈“三明治”样结构;C2神经的腹侧支恒定地跨过椎动脉的第2部分后方;头外侧直肌由于连接颈静脉孔后缘的颈静脉突,是判断颈静脉孔和面神经的标志。当椎动脉穿过硬膜时,进入一个纤维通道,内含脊髓后动脉、齿状韧带、第1颈神经、副神经的脊髓根。结论枕下三角和C2神经的腹侧根是辨别椎动脉的重要标志;头外侧直肌是识别静脉孔的重要标记;枕髁的磨除有利于增大操作空间,磨除枕髁时应避免损伤舌下神经;后颅窝手术要注意小脑后下动脉的变异。

Objective To provide anatomical basis for the suboccipital transcondylar approach. Methods 15 adult cadaver heads were anatomized to study the approach under microscope. The study was divided into three stages, including muscular stage, the epidural stage and the subdural stage. Results The suboccipital triangle consisted of the rectus capitis posterior major muscle, the superior oblique muscle, and the inferior oblique muscle. The structures in the triangle were VA and the C1 nerve, both of which lay in a groove on the arch of the altas. The VA and C1 nerve are surrounded by a rich venular plexus. The shape of these structures was like a sandwich. Ventral Ramus C2 always circled the second part of the VA and became the important mark of VA. The rectus capitis lateralis attached to the posterior edge of the jugular foramen, providing a landmark to estimate the positions of the jugular foreman and the facial nerve. While piercing the dura, the VA was encased in a fibrous tunnel that bound the posterior spinal artery, the entate ligament, the first cervical nerve and the spinal accessory nerve to the VA. Conclusion The suboccipital triangle and the dorsal root of C2 were the important masks of the VA. The rectus capitis lateralis provided a landmark for estimating the position of the juglar formen and the facial nerve. Drilling the condyle was benefit to expand the surgical space. We should avoid injurying the hypoglossal nerve while drilling the condyle and attach great importance to the variation of the posterior inferior cerebellar artery during the operation.