Singleton Jennifer M., Hefner Matthew
University of Colorado
Louisiana State University
Spinal cord compression can result from a myriad of both atraumatic and traumatic causes. The spinal column, comprised of numerous soft tissue and bony structures, is built to provide the body’s structural support and protect the spinal cord and exiting nerve roots. The encased spinal cord depends upon this stability. However, it is simultaneously vulnerable to various compressive phenomena, such as the expansion of blood products, neoplastic disease, infectious collections, or protrusion of bone or intervertebral disc within the limited area of the fat-filled spinal epidural space and meninges. A simplified overview of spinal anatomy is discussed below: The spine comprises 33 vertebrae: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral (fused), and 4 coccygeal (fused). The 26 non-fused portions of the spine are separated by cartilaginous intervertebral disks and supported by ligaments, including the anterior and posterior longitudinal ligaments. Each neural foramen (nerve root exit site) is bounded superiorly by a pedicle, immediately inferiorly by a disc space, posteriorly by facet joints, and anteriorly by the vertebral body. The spinal cord is approximately 40 cm long, extending from the foramen magnum to the L1-L2 vertebrae. The cervical and lumbar enlargements of the spinal cord, responsible for innervation to the upper and lower extremities, span from C5-T1 and L2-S3, respectively. The spinal cord tapers down to its caudal tip, the conus medullaris, between T10-L1, where the non-neural filum terminale then extends downward to the S2 vertebra. Paired lumbosacral nerves extend caudally, comprising the cauda equina until exiting the spinal column at their corresponding foramina. Vascular supply to the spinal cord includes the anterior spinal artery, supplied superiorly by the vertebral and paired posterior spinal arteries. The anterior spinal artery provides approximately two-thirds of the blood supply to the spinal cord, and the paired posterior spinal arteries provide the remaining one-third. The anterior and posterior spinal arteries receive additional blood flow from radicular arteries, the largest of which is the artery of Adamkiewicz originating from the aorta. The artery of Adamkiewicz is most commonly located between the T8-L4 levels on the left side. The spinal epidural space is bordered anteriorly by the vertebral body and posteriorly by the dura mater. It contains fat, arteries, and venous plexus. The epidural space is larger along the thoracolumbar spine, corresponding to a higher likelihood of spinal epidural abscess in this region.
脊髓受压可由多种非创伤性和创伤性原因引起。脊柱由众多软组织和骨性结构组成，其作用是为身体提供结构支撑并保护脊髓及发出的神经根。被包裹的脊髓依赖于这种稳定性。然而，它同时也易受到各种压迫现象的影响，比如血液成分的扩张、肿瘤性疾病、感染性积液，或者在充满脂肪的脊髓硬膜外间隙和脑膜的有限区域内骨或椎间盘的突出。下面将对脊柱解剖结构进行简要概述：脊柱由33块椎骨组成：7块颈椎、12块胸椎、5块腰椎、5块骶椎（融合）和4块尾椎（融合）。脊柱的26个非融合部分由软骨性椎间盘分隔，并由韧带支撑，包括前纵韧带和后纵韧带。每个椎间孔（神经根出口处）上方由椎弓根界定，下方紧邻椎间盘间隙，后方由关节突关节界定，前方由椎体界定。脊髓长约40厘米，从枕骨大孔延伸至L1 - L2椎体。脊髓的颈膨大及腰膨大分别负责上肢和下肢的神经支配，范围分别从C5 - T1和L2 - S3。脊髓向下逐渐变细至其尾端，即脊髓圆锥，位于T10 - L1之间，在此处非神经的终丝向下延伸至S2椎体。成对的腰骶神经向尾侧延伸，组成马尾，直至在相应的椎间孔处穿出脊柱。脊髓的血管供应包括由椎动脉供应的脊髓前动脉和成对的脊髓后动脉。脊髓前动脉为脊髓提供约三分之二的血液供应，成对的脊髓后动脉提供其余的三分之一。脊髓前动脉和脊髓后动脉从根动脉获得额外的血流，其中最大的根动脉是起源于主动脉的Adamkiewicz动脉。Adamkiewicz动脉最常见于左侧T8 - L4节段之间。脊髓硬膜外间隙前方由椎体界定，后方由硬脑膜界定。它包含脂肪、动脉和静脉丛。硬膜外间隙在胸腰椎处较大，这与此区域发生脊髓硬膜外脓肿的可能性较高相对应。
