寰椎横韧带的形态特点及其生物力学特性研究

Anatomic and biomechanical studies of transverse ligament of atlas

目的 :研究寰椎横韧带的形态特点及其抗拉伸性能。方法 :成人寰枢椎固定标本 2 4例及新鲜寰椎横韧带标本 9例。测量横韧带中点处的厚度、宽度以及左右两端的宽度。取 2例新鲜横韧带标本行组织学片观察。 7例新鲜横韧带标本 ,通过MTS -85 8材料试验机测试其抗拉伸性能。结果 :寰椎横韧带的长度为 ( 2 0 .0± 2 .4)mm ;中点处的厚度为 ( 2 .1± 0 .5 )mm ;中点处的宽度为 ( 10 .7± 1.6)mm ;左右两端的宽度分别为 ( 6.6± 1.1)、( 6.7± 1.0 )mm ;左右两端的厚度分别为 ( 3 .8± 1.1)、( 3 .7± 1.1)mm。横韧带与枢椎齿突的关系可分为三种类型 :①横韧带将齿状突后面完全包裹 ,占 3 0 .3 % ( 10例 ) ;②横韧带包裹齿状突后面的大部 ,超过 1/ 2 ,占 5 4.5 % ( 18例 ) ;③部分覆盖齿状突的后部 ,不超过其 1/ 2 ,占 14 .5 % ( 5例 )。寰椎横韧带的齿状突面的中部可见有纵行的纤维 ,组织切片显示为较疏松的结缔组织。横韧带的最大载荷为( 60 5 .5± 89.6)N ,最大变形量为 ( 4 .3± 0 .5 )mm。结论 :( 1)本文结果与国外的相关报道比较 ,在长度上较白种人稍短 ,而与黄种人相近 ,这与人种的高矮有关。 ( 2 )寰椎横韧带与齿突接触面的中部可有条索状的疏松结缔组织存在。 ( 3 )寰椎横韧带与枢椎齿突的关系不恒定 ,

Objectives: To report the anatomic parameters and the anti-stretch property of transverse ligament of atlas. Methods: 24 adult C 1～C 2 fixated specimens and 9 fresh transverse ligament specimens were used. To observe the anatomic characters of the transverse ligament of atlas, the length, thickness and the width in center and the widths in both sides were measured. Two of the nine fresh transverse ligament specimens were observed in histology, and seven of them were used to test the anti-stretch property on a material testing machine (MTS 858 Bionix test system, USA). Results: The length of the transverse ligament of atlas was 20.0±2.4 mm, the thickness of the center was 2.1±0.5 mm, the width of the center was 10.7±1.6 mm, the widths of left and right end were 6.6±1.1 mm and 6.7±1.0 mm respectively, and the thickness of the two end were 3.8±1.1 mm and 3.7±1.1 mm respectively. The relationship between the transverse ligament of atlas and the odontoid process of axis was classified by three types: 1. The odontoid process was completely coated by the transverse ligament from behind, 10 of 33 (30.3%) were observed in our study. 2. The odontoid process was partly, but more than 1/2, coated by the transverse ligament, 18 of 33 (54.5%) were observed in our study. 3. The odontoid process was partly, but less than 1/2, coated by the transverse ligament, 5 of 33 (15.2%) were observed in our study. In the central part of the surface of the transverse ligament, which was facing the odontoid process, some longitudinal fibers had been found and confirmed to be loose connective tissue in histology. The average of the max load of the transverse ligament was 605.5±89.6N, and the average of the max deformation of the transverse ligament was 4.3±0.5mm. Conclusions: Contrast to the foreigner's, the transverse ligament of atlas of Chinese people is shorter than that of White race, and it almost the same as that of Yellow race. In the surface of the transverse ligament of atlas, which is facing the odontoid process, there may have some loose connective tissue. The relationship between the transverse ligament and the odontoid process is not invariable which may be the anatomic base of the dens fracture.