经皮椎弓根螺钉技术的解剖学基础及其临床意义

目的：为经皮椎弓根螺钉技术提供解剖学基础并在此基础上分析经皮植入椎弓根螺钉较常规开放植入椎弓根螺钉临床应用的优点。方法：选用10具经防腐固定，在解剖显微镜下对胸腰段脊柱后部结构进行逐层解剖，重点观测脊神经后支及其分支、脊柱节段动静脉的后支的来源、走行以及分布规律。结果：脊神经后支的内侧支经骨纤维管下行沿途支配横突棘肌，支配下方小关节突、筋膜和韧带。外侧支向外下行走，沿途支配背部深层肌肉。节段动脉的后支在椎间孔的上外方绕向后下方，走行于脊神经的下方和下位脊椎上关节突的外方，分为内外两支穿行于腰部深层肌肉。节段静脉后支与同名动脉伴行，并与对侧、相邻节段同名静脉在棘突和横突部位构成静脉丛。结论：避免损伤脊神经后支和节段动静脉的后支并运用可视化操作系统的经皮椎弓根螺钉植入技术，是微创脊柱外科一种新的技术手段。

Anatomic basis of percutaneous pedicle screw and its clinical significance

Objective:To provide minimally invasive spinal surgery with the anatomical basis for the percutaneous pedicle screw. Methods: The origin, branch and distribution of the posterior rami of spinal nerves and the dorsal branches of the segmental artery, vein in the thoracolumbar region were observed on 10 adult specimens. Results: The posterior branch of the segmental artery in the thoracolumbar region arised laterally to the intervertebral foramen and runed dorsocaudal, inferior to the superior articular process of the vertebral below, and the dorsal branchs of the segmental veins paralleled their corresponding arteries. The posterior rami emerged from the intervertebral foramen posterior to the superior articular process of the below of the vertebral, and divided into their terminal medial and lateral branchs. The medial branch of the posterior ramus of the spinal nerve coursed dorsally from the lateral aspect of the superior articular process to the root of the transverse, and was attached to the periosteum by fibers. The lateral one entered into the deep muscles of the back. Conclusions: Only through the percutaneous pedicle screw can we avoid mechanical damage to the posterior ramus of the spinal nerve, segmental vessel and retract greatly the paraspinous muscle.