脊柱腰骶段是人体上半身重量向下肢传递的重要组成结构，承受着较大的压力与剪切力，也是椎体骨折、滑脱、椎间盘突出、结核等疾病的高发部位。由于该区域解剖关系复杂，虽然单纯后路病灶清除内固定、前路病灶清除联合后路内固定以及单纯前路病灶清除植骨融合等多种术式被用于上述疾病的治疗，但依然各有利弊，至今尚无最优的治疗方案。因此，积极探寻适用于腰骶段脊柱疾病的最佳治疗方案具有十分重要的临床意义。 目的：设计一种新型的治疗术式——一期侧前路病灶清除钛笼植骨融合联合双钉棒系统内固定，为临床上治疗腰骶段脊柱疾患尤其是结核、肿瘤、骨折等疾病提供新的思路。 方法： 1.通过文献回顾以及尸体标本解剖研究熟悉腰骶段脊柱及其周围毗邻血管、神经等重要组织结构的解剖特点，为前入路手术提供详细、全面的解剖学支持。 2.通过尸体标本体外生物力学测试对一期侧前路病灶清除钛笼植骨融合联合双钉棒系统内固定的力学性能进行初步评估并与单纯后路双钉棒固定进行对比研究，为该新型术式的临床应用奠定生物力学基础。 3.对前期通过一期侧前路病灶清除钛笼植骨融合联合双钉棒系统内固定治疗的腰骶段脊柱结核患者进行回顾性研究，总结该术式在治疗腰骶段脊柱结核的临床疗效、适应症及禁忌症，为其在临床上的进一步推广提供有益指导。 结果： 1.腰骶段脊柱一般由尾侧腰椎、骶骨、椎间盘以及附属韧带构成，尾侧腰椎一般指L3、L4、L5，骶骨由5节骶椎融合而成，呈向前凹陷的三角形，底向上，尖向下，上缘中份向前凸起形成岬。诸多研究曾对腰骶段脊柱进行过解剖测量，具体参数见正文。目前前入路手术根据手术路径的差异主要分为前方腹膜后入路，经腹膜入路及外侧腹膜后入路三种，三种术式各有利弊，均在临床上获得一定应用。腰骶段前方重要组织结构主要有腹主动脉、下腔静脉、髂总动脉及其分支、髂总静脉及其属支、神经干等。诸多学者曾对腰骶段血管的走行、分布进行了解剖学研究，具体参数见正文部分。通过对15具尸体标本腰骶段主要结构的解剖观察及测量发现腰骶段主要血管的分布及解剖参数与文献回顾相似。 2.体外生物力学研究结果显示通过侧前路双钉棒固定可以使腰骶段脊柱在前屈、左右侧弯以及轴向压缩方向上较后路固定获得更好地稳定性，而其在左右旋转方向上的稳定性与后路固定相似。虽然前路固定在背伸方向上的即刻稳定性较后路固定差，但是我们认为随着钛笼植入融合，前路固定在上述方向上的稳定性会逐渐增强，可能并不亚于后路固定。 3.对30例通过一期侧前路病灶清除钛笼植骨融合联合侧前方双钉棒系统内固定治疗的腰骶段脊柱结核患者的回顾性研究显示上述治疗方案不但可以对病灶进行彻底清除而且可以较好的重建手术部位的稳定性及生理曲度，避免结核的再次复发。 结论：在严格遵循手术适应症的前提下，通过一期侧前路病灶清除钛笼植骨融合联合侧前方双钉棒系统内固定治疗腰骶段脊柱结核可以获得较满意的临床疗效，值得在临床上进一步推广。此外，在遵循严格适应症的前提下，该新型术式在治疗腰骶段脊柱肿瘤、骨折等方面也存在一定的应用可能，但其治疗效果仍需进一步临床研究。 关键词：腰骶段脊柱；解剖；生物力学；手术入路；结核 论文类型：应用基础

 Lumbosacral spine is an important component which transmits the upper body weight to the lower limbs and bears the greater pressure and shear force. There are more diseases in this site such as vertebral fracture, spondylolisthesis, inter-vertebral disc herniation, tuberculosis. Due to the complex anatomy of the region, although many kinds of operation such as posterior spinal fusion alone, anterior spinal fusion plus posterior spinal fusion and anterior spinal fusion are used for the treatment of the above diseases, all of them have their own advantages and disadvantages and so far there is no optimal treatment plan. Therefore, it is very important to explore the optimal treatment plan for lumbosacral spinal disease. Objective: Developing a new type of operation, one-stage anterior debridement and fusion combined with dual screw-rod anterior instrumentation to provide new ideas for clinical treatment of lumbosacral spinal diseases, especially tuberculosis, tumor, fracture and other diseases. Methods: 1.The anatomical characteristics of important structures of the lumbosacral spine and its surrounding adjacent blood vessels and nerves were studied by literature review and autopsy in order to provide detailed and comprehensive anatomical support for anterior approach surgery. 2.The biomechanical test in vitro on the specimen was carried out to preliminary assess the mechanical performance of the new type operation, one-stage anterior debridement and fusion combined with dual screw-rod anterior instrumentation and compared with double screw rod fixation by only posterior approach,in order to lay biomechanical basis for the clinical application of the new operation. 3.A retrospective study was carried out on patients with lumbosacral spinal tuberculosis treated by one-stage anterior debridement and fusion combined with dual screw-rod anterior instrumentation.To summarize the clinical efficacy, indications and contraindications of the operation in the treatment of lumbosacral spinal tuberculosis, and provide useful guidance for the further promotion in clinic. Results: 1.The lumbosacral spine is composed of the caudal lumbar vertebra, sacrum, intervertebral disc and accessory ligament. The caudal lumbar spine generally refers to L3, L4 and L5. The sacrum is composed of five sacral vertebrae and is formed by a forward concave triangle, the bottom up, the tip downward, and the upper margin of the upper edge protruding forward to form the headland. Many studies have conducted anatomic measurement of the lumbosacral spine, and the specific parameters are shown in the text. According to the surgical path, the anterior approach surgery was mainly divided into the anterior retroperitoneal approach, the transperitoneum approach and the lateral retroperitoneal approach and all of them had their own advantages and disadvantages. The main structure of the anterior sacrosacral region is the abdominal aorta, the inferior vena cava, the common iliac artery and its branches, the common iliac vein and its branches, the nerve trunk, etc. Many scholars have conducted anatomical studies on the walking and distribution of lumbosacral vessels, and the specific parameters are shown in the main body. The distribution and anatomical parameters of the main blood vessels in the lumbosacral segment were similar to the literature review by observing and measuring the main structures of the lumbosacral segments of 15 cadaver specimens. 2.The resuts of biomechanical study in vitro showed that one-stage anterior debridement and fusion combined with dual screw-rod anterior instrumentation can make lumbosacral spine obtain better stability in forward bends, lateral bending and axial compression direction, and its stability was similar with posterior fixation in the direction of rotation. Although the immediate stability of anterior fixation in extension was poor than that of posterior fixation, we think that the stability of the anterior fixation in extension will gradually strengthen with titanium cage fusion with the surrounding bone and may not be poorer than posterior fixation. 3.The results of retrospectively study showed that the treatment of one-stage anterior debridement and fusion combined with dual screw-rod anterior instrumentation can not only thoroughly remove the lesion and better reconstruct the stability of the surgical site and physiological curvature, but also avoid the recurrence of tuberculosis. Conclusions: Under the premise of strictly following surgical indications, one-stage anterior debridement and fusion combined with dual screw-rod anterior instrumentation can obtain satisfactory clinical effect in the treatment of lumbosacral spinal tuberculosis and the operation is worth popularizing in clinic further. In addition, on the premise of following strict indications, the new surgical method is also possible in the treatment of lumbosacral spinal tumors and fractures, etc., but its therapeutic effect still needs further clinical research. KEY WORDS: Lumbosacral spine; Anatomy; Biomechanics; Surgical approach; Tuberculosis TYPE OF DISSERTATION: Application Fundamentals