髂腰韧带CT三维显示及其在腰椎节段定位中的作用

CT three-dimensional imaging of the iliolumbar ligament and its significance on locating lumbar vertebral segments

目的:研究髂腰韧带能否在CT上显示以及髂腰韧带在腰椎节段定位中的作用。方法:128例腰椎患者进行了CT容积扫描检查,采用横断、矢状、冠状多平面重建图像分析髂腰韧带的结构特点。128例患者中有11例为移行椎患者,均经X线片证实。结果:117例腰骶正常节段的患者髂腰韧带均起自L5横突。83%的髂腰韧带前、后束之间间隔脂肪组织,前、后束可分辨,横断位上前束较扁,向外侧走行止于髂棘后1/3内侧缘,后束较短而厚,向外后侧走行止于髂后上棘内侧骨面,冠状位上髂腰韧带前、后束均呈类三角形改变,尖端指向髂棘,底边与L5横突相连,矢状位上髂腰韧带前束呈薄条带状或小点状,后束呈宽厚条带状或结节状。17%的髂腰韧带前、后束之间缺乏脂肪组织,前、后束不能分辨,横断位上韧带呈宽厚条带状或扇形向外后方行走,止于髂棘,冠状位上韧带呈类三角形改变,矢状位上韧带呈结节状或不规则条带状改变。以髂腰韧带作为L5椎体水平的定位标记,11例移行椎均准确定位。结论:CT三维多平面重建可准确显示髂腰韧带的形态和走行特点。髂腰韧带起自L5横突,根据这一特点能对腰椎节段进行准确的定位,特别是在合并有腰骶部移行椎的患者。

Objective： To determine whether iliolumbar ligament can be identified on CT and its clinical effects on locating lumbar vertebral segments. Mothods： CT studies from 128 lumbar spines were performed with volume scans. Multiple plane reconstruction of axial, sagittal and coronal planes was used for analysis of the structural characteristics of the iliolumbar ligaments. 11 cases with lumbosacral transitional vertebrae were verified radiologically. Resuls： The iliolumbar ligaments originated from L5 transverse processes in 117 patients with normal lumbosacral segmentations. The anterior and posterior bands can be identified in 83% iliolumbar ligaments. Fat tissue existed between the anterior and posterior bands. On axial images, the anterior bands were thin, directed laterally to the posterior 1/3 part of the medial surface of the iliac crest, while posterior bands were short and thick, expanded laterally and posteriorly to the inner lip of the posterior superior iliac spine. On coronal images, the iliolumbar ligaments demonstrated as a triangular shape, pointed toward iliac crest with its bottom connected with L5 transverse process. On sagittal images, anterior bands showed the shape of flat streak or dot, while posterior bands demonstrated as thick and strong streak or nodular shape. The anterior and posterior bands cannot be identified in 17% iliolumbar ligaments because of the lack of fat tissue between them. Using iliolumbar ligaments as a marker of the L5 vertebral level, 11 lumbosacral transitional vertebrae were correctly numbered. Conehutiom： Accurate imaging of the shape and orientation of the iliolumbar ligaments is achieved with CT three-dimensinnal multiple plane reconstruction reformatting. The iliolumbar ligament always arises from L5, its position can be used to confidently assign lumbar levels, especially patients with lumbosacral transitional vertebrae.