膈肌脚在上腰椎爆裂骨折手术中复位作用的解剖研究

The anatomic study on the function of crura of diaphragm in the surgical reduction of upper lumbar burst fracture

目的探讨膈肌脚的解剖形态及其在经伤椎椎弓根螺钉内固定治疗爆裂骨折复位过程的作用。方法（1）成人躯干标本24具，男16具，女8具，游离腰椎前方双侧膈肌脚，观测其跨椎体节段数、长度、宽度与厚度；（2）将该24具标本制作骨折复位模型。进行实体测量并X线机动态的记录伤椎及椎体前方膈肌脚形态结构的变化。结果（1）75％（18例）膈肌脚上端至T12下缘水平，下端多起自L3/4椎间，右侧稍长。右侧膈肌脚长（12．1±1．8）cm，与前纵韧带融合长度为（7．0±1．1）cm；左侧膈肌脚长（9．6±1．5）cm，融合长度（5．3±1．1）cm。膈肌脚宽度与厚度随着节段水平变化而变化。（2）手术中各步骤复位量进行对比，发现伤椎的Cobb角和矢状径在俯卧位时可以得到最大量的恢复。结论（1）正常成人有发达的膈肌脚附着在T12～L4前面，膈肌脚与前纵韧带融合；双侧强大的膈肌脚在骨折时对椎体具有保护作用，使骨折碎片不至于移位过大。（2）经伤椎椎弓根内固定手术过程中，每一个步骤都有一定的复位作用；俯卧位是手术复位中最关键的一步。

Objective To investigate the anatomical mechanism and function of crura of diaphragm during the reduction process in the fracture of L1-3 spinal vertebrae. Methods （1） 24 corpses were dissected to show diaphragm crura in front of L1-3 vertebrae. The origin and end of the two diaphragmatic crurae, the count of the vertebrae level covered by the diaphragm crura, the length, width and thickness in different level of the individual the diaphragm crus, and the length in a crus fused to the anterior longitudinal ligament were measured; （2） Four intact corpses were chosen to imitate the process of vertebral fracture and reduction. All specimens were managed to be operated from the posterior, using intermediate screws through the fractured vertebrae in short segment pedicular fixation. In the course of operation, the changes of vertebrae each step with X-ray were record. Results The overall length of right crus is （12.1±1.8） cm, with （7.0±1.1）cm fused with the anterior ligament, and the muscular length of the right crus is （6.4±1.4） cm, the tendon length is （5.6± 1.1） cm; the overall length of left crus is （9.6±1.5） cm, with （5.3±1.1） cm fused with the anterior ligament, and the muscular length of right crus is （4.9±1.0） cm, the tendon length is （4.8±1.3） cm. The width and thickness of crura changes in different level, when the length and width, thickness of diaphragm crurae in the left and right sides were compared, there was significant difference, with the right crus being stronger than the left one. And there were significant differences between every step and the previous one. Conclusions （1） Strong diaphragm crura attached to the thoracolumbar vertebrae anteriorly, together with the longitudinal ligament forms “soft-tissue-splint”, which is helpful to reduce the bony fragments. （2） Every operational step makes some kind of reduction, the prone position is of the most significant importance in achieving the greatest reduction.