Thoracolumbar Fracture: Posterior Instrumentation Using Distraction and Ligamentotaxis Reduction胸腰椎骨折：采用撑开和韧带整复复位后路器械固定Thoracolumbar burst fracture occurs when the vertebral body is subjected to a significant axial force that brings about compression failure of the anterior and middle columns of the spine.1 Most burst fractures involve the thoracolumbar junction, which is uniquely susceptible to this type of injury because of its transitional anatomy and its location between the stiff, kyphotic thoracic spine and the more mobile, lordotic lumbar region. Unlike purely compressive fractures, in which the middle spinal column remains intact, burst injuries typically are associated with some degree of spinal canal occlusion, which may result in neurologic deficits.当椎体受到轴向暴力产生脊柱前、中柱压缩破坏时可发生胸腰椎爆裂性骨折。
大多数爆裂性骨折容易发生在胸腰段连接处，主要是因为胸腰段解剖结构和所处位置不同，胸段特点是活动度小并向后凸，而腰段活动度较大且向前凸。
单纯性压缩性骨折时脊柱中柱保持完好，而典型的爆裂性损伤与单纯压缩骨折不同，它可发生一定程度的椎管受累，从而导致神经功能障碍。
Many stable thoracolumbar burst fractures are treated nonsurgically with external immobilization and early ambulation. However, the patient who exhibits spinal instability, progressive spinal deformity, or an incomplete spinal cord injury is often an appropriate candidate for surgical intervention. In these presentations, the goals of surgery are to restore spinal stability through fracture stabilization and to improve functional outcomes by decompressing the neural elements.许多稳定的胸腰段爆裂性骨折采用制动和早期下床活动等非手术治疗。
然而对于脊柱不稳定、进行性脊柱畸形或不完全性脊柱损伤的患者通常适合手术治疗。
对这些情况进行手术的目的在于通过稳定骨折恢复脊柱的稳定性、通过减压改善神经功能。
There is a great deal of controversy regarding the optimal surgical approach (ie, anterior, posterior, circumferential) for treating a patient with a thoracolumbar burst fracture. Posterior instrumentation techniques are frequently used in this clinical scenario because they facilitate fracture reduction and subsequent arthrodesis. At the same time, indirect decompression of the spinal canal may be accomplished through distraction and ligamentotaxis, a process that effectively shifts the retropulsed bony fragments anteriorly away from the neural structures. The posterior-only approach has become even more popular with the development of modern pedicle screw systems, which provide reliable fixation through the anterior, middle, and posterior columns, thereby increasing the rigidity of these constructs and allowing application of greater axial and rotational forces to the spine.关于最佳手术入路(如前路、后路、前后联合)治疗胸腰椎爆裂性骨折患者存在大量争议。
在临床上后路器械固定技术通常用于此类患者，这种手术方式有利于骨折复位和融合。
同时，撑开和韧带整复可以完成椎管间接减压，这种方法有效后复位骨折碎片，使其远离神经结构。
随着现代椎弓根螺钉系统的发展，后方入路变得更加普及，它通过前、中和后柱提供可靠的固定，因此增加了这些结构的刚度，脊柱可承受更大的轴向和旋转暴力。
Indications and Contraindications适应证和禁忌证The optimal surgical approach for the patient with a thoracolumbar burst fracture is determined by neurologic status, presence of a kyphotic deformity, evidence of spinal canal compromise orinstability on imaging studies, and presence of other nonspinal injuries. Isolated posterior instrumented spinal fusion is best suited for an unstable burst fracture in the patient with no neurologic deficit and in whom direct decompression is unnecessary. A posterior procedure also may be indicated for an acute burst fracture associated with either neurologic injury or moderate spinal canal occlusion in which distraction and ligamentotaxis may result in the indirect reduction of the displaced bony fragments.胸腰段爆裂性骨折患者的最佳手术方式取决于神经状况、有无后凸畸形、有无椎管受累或影像学上的不稳、有无其他非脊柱损伤。
单独后路器械脊柱融合是无神经功能障碍不稳定爆裂性骨折患者的最佳适应证，这些患者不需要行直接减压。
后路手术也适用于存在神经损伤或中度椎管狭窄的急性爆裂性骨折，撑开和韧带可以间接复位复位骨折碎片。
Several studies have demonstrated that distraction in conjunction with ligamentotaxis may reduce spinal canal compression by up to 50%, usually to <20% of the total area.2-5 Flexion-distraction and soft-tissue Chance injuries with disruption of the posterior ligamentous complex also may be addressed with this technique, in which the instrumentation supplements the deficient posterior tension band. Likewise, successful reduction and stabilization of fracture-dislocations and shear injuries with extensive translational or rotational instability is more easily achieved using posterior pedicle screws.已有研究表明撑开联合韧带整复可以复位椎管压迫至50%，通常小于总面积的20%。
屈曲牵拉和存在后方韧带复合体断裂的软组织Chance损伤也可以采用这项技术，器械固定可以弥补后方张力带缺失。
同样，采用后路椎弓根钉可以更容易获得骨折脱位、存在广泛平移或旋转不稳定的剪切力损伤的成功复位和稳定。
In the patient with complete thoracic-level spinal cord injury with relatively limited potential for meaningful neurologic recovery, posterior arthrodesis may be indicated to maintain proper alignment, prevent the progression of further deformity, and provide immediate stability. The latter is essential for nursing care and rehabilitation. This strategy also may be considered for a fracture involving the posterior elements that is accompanied by neurologic deficit, for which a laminectomy may be necessary to release entrapped roots or repair traumatic dural tears.为给完全性胸髓损伤的患者提供神经功能恢复的相对有限的可能性，后路融合可以恢复脊柱正常序列、预防畸形进一步发展并提供即刻的稳定性，接下来需要重视护理和康复治疗。