L5/S1椎间孔内韧带的形态和分布规律

Morphology and distribution of the intraforaminal ligaments at the L5/S1 level

中文关键词:  椎间孔内韧带  L5/S1椎间孔  硬膜外腔导管松解

英文关键词:Intraforaminal ligament  L5/S1 intervertebral foramen  Endoscopic adhesiolysis

中文摘要:

  【摘要】 目的：探讨L5/S1椎间孔内韧带的形态、分布规律并评价其临床意义。方法：取5具防腐和5具新鲜冰冻正常成人腰骶部标本（年龄42~80岁，平均51岁）。仔细剔除脊柱周围的软组织，从正中矢状位锯开脊柱。找出L5/S1神经根并沿椎间孔小心去除周围脂肪和筋膜等软组织。在肉眼及手术显微镜下观察韧带的形态、走行、起始位置及分布特点，用游标卡尺在手术显微镜下测量其长度、宽度及直径或厚度。用HE染色和Masson三色染色法分析对比不同类型韧带的组织学类型。结果：在20个L5/S1椎间孔内共发现215条韧带，其中条带形90条，条索形125条；连接神经根到横突或椎间孔内壁的放射状韧带181条（84.2%），连接椎间孔周围组织横跨在椎间孔内的横跨状韧带34条（15.8%）；放射状韧带出现率与横跨状韧带出现率的比较有统计学差异（Z=-3.928, P=0.000）。在L5/S1椎间孔内口（73条，34.0%）、中间（102条，47.4%）及外口（40条，18.6%）区域均有分布。韧带长度多变，为1.43~19.01mm；厚度最厚处达3.46mm。光镜下，HE染色提示椎间孔内韧带由纤维结缔组织构成且部分韧带内包含小血管组织，Masson三色法染色提示椎间孔内韧带由大量的胶原纤维和少量的弹性纤维构成。放射状韧带与横跨状韧带组织学表现无明显差异。结论：L5/S1椎间孔内韧带主要分为条带形和条索形两种形状。椎间孔内放射状韧带比横跨状韧带出现率高。经骶骨裂孔硬膜外腔导管粘连松解术前应掌握其分布规律并在术中辨别并予以正确松解，以减少并发症的发生。

英文摘要:

  【Abstract】 Objectives: To identify the intraforaminal ligaments in relation to the L5/S1 intervertebral foramen, and to evaluate their clinical significance. Methods: 5 embalmed cadavers and 5 fresh cadavers were studied(age: 42 to 80 years， average age, 51 years). The soft tissues around the spine were removed and the structure in median sagittally was exposed. The spinal nerve roots within the fascia were identified at their individual intervertebral foramen by meticulously removing the overlying remnants of the muscle, adipose tissue and the fascia. The quantity, morphology, origin, insertion and the spatial orientation of intraforaminal ligaments in the L5/S1 region were observed. And the length, width and diameter or thickness of ligaments were measured with a vernier caliper. Comparisons of different ligament histological types with HE staining and Masson trichrome staining were carried out and analyzed. Results: A total of 215 ligaments were found in 20 L5/S1 intervertebral foramina, and there were 90 strip-shaped ligaments and 125 trabs-shaped ligaments; there were 181 ligaments(84.2%) connecting the nerve root to the transverse or the intervertebral foraminal wall, which were characterized as radiating ligaments, and 34 ligaments(15.8%) connecting the intervertebral foramen and the organization across the intervertebral foramen, which were characterized as transforaminal ligaments; the appearance rate of radiating ligament and that of transforaminal ligament showed statistical significance(Z=-3.928, P=0.000). The IFLs could be found from the entrance zone in 73 ligaments(34.0%), mid zone in 102 ligaments(47.4%) and the exit zone in 40 ligaments(18.6%) in the L5/S1 intervertebral foramen. Ligament length varied from 1.43mm to 19.01mm; the thickest was 3.46mm. Under the microscope, eosin(HE) staining indicating the intraforaminal ligaments were composed of fibrous connective tissues and part of them contained small blood vessel tissues; Masson trichrome staining indicating intraforaminal ligaments were composed of a large amount of collagen fibers and a small amount of elastic fibers. There was no significant difference under the microscope about the histological features between intraforaminal ligaments and transforaminal ligaments. Conclusions: The intervertebral foraminal ligaments are mainly divided into strips and trabs. The appearance rate of radiating ligaments in intervertebral foramen is much higher than that of transforaminal ligaments. Therefore, surgeon should be cautious of endoscopic spinal surgery to avoid nurse root injury.