设计国人直肠后间隙入路轴向腰骶椎融合内固定的影像学测量

Imaging measurement for internal fixation design of axial lumbosacral vertebral fusion via posterior rectal space

背景:经骶骨前入路的经皮腰骶椎前柱内固定系统即AxiaLIF系统先后在美国及欧洲应用于临床,取得较好的临床疗效。但是国人与欧美人腰骶椎的解剖差异较大,国外内固定系统能否可以直接用于国人尚不明确,且价格昂贵,不适合中国国情,同时该内固定系统在应用过程中出现了一系列的问题,如能优化轴向螺钉设计,该术式在国内将会有更大的推广价值。目的:通过测量国人正常人群腰椎侧位片及腰椎CT L_5、S_1椎体横断面,为设计适合国人的轴向螺钉提供解剖学数据。方法:①选择国人正常成人腰椎侧位片男35例,女30例,分别测量S_1椎体轴向高度、L_5/S_1椎间隙高度、L_5椎体轴向高度,为轴向螺钉的长度设计提供解剖学数据;②选择成人腰椎CT片男26例,女24例,测量腰椎CT L_5、S_1椎体经椎弓根层面的横状径与矢状径,为轴向螺钉的直径设计提供解剖学数据。结果与结论:①国人男、女性腰椎侧位片S_1椎体轴向高度为(26.76±3.94)mm和(22.91±2.91)mm(P<0.05)、L_5/S_1椎间隙高度为(12.62±1.90)mm和(11.92±1.78)mm(P>0.05)、L_5椎体轴向高度为(29.12±2.18)mm和(26.91±2.47)mm(P<0.05);②国人男、女性腰椎CT L_5横状径为(47.34±4.31)mm和(43.12±3.71)mm(P<0.05),S_1横状径为(49.18±4.14)mm和(46.11±4.44)mm(P<0.05),L_5矢状径为(34.48±2.32)mm和(33.03±3.48)mm(P>0.05),S_1矢状径为(35.65±4.28)mm和(33.53±3.26)mm(P>0.05);③综上,通过国人腰椎侧位片中轴线及腰椎CT L_5、S_1椎体横断面的测量,可为设计出适合国人腰骶椎融合的轴向螺钉提供解剖数据;根据该影像学测量方法对患者术前影像学资料进行分析,可以预判患者行该手术方式的可行性,并对内固定型号选择做出预估,进行个性化置钉。

BACKGROUND： The minimally invasive axial lumbar interbody approach （AxiaLIF） for L4–S1 fusion has been applied in America and Europe, and has obtained satisfactory curative efficacy. Because of significant anatomical differences between Chinese and Europeans and Americans, whether AxiaLIF is appropriate for Chinese remains unclear. Moreover,there are some problems in the application of AxiaLIF, so how to optimize AxiaLIF is a key to its promotion in China.OBJECTIVE： To provide anatomical data for the design of axial screws suitable for Chinese through measuring the mid axial line of the lateral lumbar radiograph and cross sections of L5 and S1 on lumbar CT in normal Chinese population.METHODS： The lateral lumbar radiographs from Chinese healthy population were selected, including 35 males and 30 females, the axial height of S1, the disc distance between L5 and S1, and the axial height of L5 were measured so as to provide anatomical data for designing the length of the axial screw. The transverse and sagittal diameters of L5 and S1 in the lumbar CT of 26 adult healthy males and 24 healthy females were measured to provide anatomical data for designing the diameter of the axial screw.RESULTS AND CONCLUSION： （1） The axial height of S1 in males and females was （26.76±3.94） mm and （22.91±2.91） mm, respectively （P 0.05）. The axial height of L5 was （29.12±2.18） mm for males and （26.91±2.47） mm for females （P 〈0.05）. （2） The transverse diameter of S1 was （49.14±4.14） mm for males and （46.11±4.44） mm for females （P 0.05）. （3） That is to say, this study provides the anatomical data for designing the axial screws suitable for the lumbar fusion of Chinese by measuring the mid axial line of the lateral lumbar radiographs and the cross sections of L5 and S1 on lumbar CT. The image measurement method can be used to analyze the preoperative images of the patients to predict the feasibility of the surgical approach and pre-select the internal fixation model for personalized screw positioning.