微创极外侧经椎间孔腰椎椎间融合术的数字化解剖研究

A digital anatomic study of minimally invasive extreme lateral transforaminal lumbar interbody fusion

目的数字化技术测量并比较微创极外侧经椎间孔腰椎椎间融合术（E—TLIF）与微创经椎间孔椎间融合术（mini—TLIF）的相关解剖参数，并通过解剖验证。方法选取门诊60例成人腰椎CT扫描资料，男30例，女30例；年龄18～55岁，平均46．3岁。应用SuperimageTM软件，三维重建实体模型，模拟E—TLIF、mini-TLIF固定，分别测量并比较L3-4,L4-5节段上E—TLIF、mini—TLIF固定的切口距正中线距离、操作通道深度（切口至关节突的距离）、融合器长度、椎弓根螺钉置入长度和角度。并在2具成年男性新鲜尸体标本上进行实际操作验证。结果图像上测量E—TLIF切口距正中线为81．3～87．6mm，操作通道深为81．6-86．9mm，融合器长为29．8～32．2mm，椎弓根螺钉长度为51．6～57．2mm，椎弓根螺钉倾角为37．20～40．4°。E．TLIF与mini．TLIF相比切口更加偏外，可以绕过下关节突，从侧后方直接处理增生内聚的上关节突；椎弓根螺钉和融合器置入角度更加倾斜，长度增加。在尸体标本上采用E—TLIF数字化设计测量值进行操作，尸体标本上测量的解剖参数：切口距正中线距离为80．0～90．0mm，操作通道深度约85．0mm，椎弓根螺钉置入倾角近40．0°，与图像测量值相近。结论通过数字化技术测量和解剖验证，与mini—TLIF相比，E—TLIF更完整地保留了脊柱后方的解剖结构，有助于提高术后即刻稳定性。

Objective To investigate the clinical feasibility of extreme lateral transforaminal lumbar interbody fusion （E-TLIF） by measuring and comparing digitally the anatomical parameters of E-TLIF and minimally invasive transforaminal lumbar interbody fusion （mini-TLIF）. Methods The lumbar CT spans of 60 adult out-patients minimdly invasive were collected for the present study. They were 30 men and 30 women, with an average age of 46.3 years （from 18 to 55 years）. The Superimage TM software was used to reconstruct the 3D lumbar models. The distance from the incision to the midline, depth of operative tunnel （from the incision to the articular process）, cage length, length and angle of the pedicle screw implanted were measure respectively at the L3-4 and IA-5 in both E-TLIF and mini-TLIF simulation groups. The E-TLIF procedure digitally designed was performed on 2 fresh cadavers to verify the feasibility of the procedure. Results By digital measurement, the distance from the incision to the midline ranged from 81.3 mm to 87.6 mm, the depth of operative tunnel from 81.6 mm to 86.9 mm, the cage length from 29.8 mm to 32. 2 mm, the length and angle of the pedicle screw implanted respectively from 51.6 mm to 57.2 mm and from 37.2° to 40.4° for the E-TLIF procedure. Compared with mini-TLIF, the E-TLIF incision was more lateral, bypassing the inferior articular process and allowing posterolateral treatment of the superior articular process; the cages and pedicle screws in the E-TLIF fixation were inserted more obliquely to increase the fixation strength. In the actual E-TLIF operations on the fresh cadavers, the distance from the incision to the midline ranged from 80. 0 mm to 90.0 mm, the depth of operative tunnel was about 85.0 mm, the angle of the pedicle screw implanted from about 40. 0°, near those digital values. Conclusion The digital anatomical mea- surement and actual operations on cadavers indicate that E-TLIF can preserve more posterior tension band of the spine and increase the immediate postoperative stability compared with traditional mini-TLIF.