组织学和 与胚胎学课件脊髓.pptVIP

The Nervous System Department of Human Anatomy, College of Basic Medicine, Zhengzhou University 雷留根 The Spinal Cord 脊髓 Position Lies in vertebral canal Continuous above with medulla oblongata at level of foramen magnum Ends below at lower border of L1 in adult; at birth at level of L3 External features A long cylindrical structure and slightly flattened anteroposteriorly, Conus medullaris （脊髓圆锥） Filum terminale （终丝） Cauda equina （马尾） Two enlargements Cervical enlargement （颈膨大）: corresponds to the C4 to the T1 segments Lumbosacral enlargement （腰骶膨大）: corresponds to the L2 to the S3 segments Fissure and sulci　沟和裂 Anterior median fissure 前正中裂 Posterior median sulcus 后正中沟 Anterolateral sulcus 前外侧沟－anterior (motor) roots emerge serially Posterolateral sulcus 后外侧沟－posterior (sensory) roots enter spinal cord, each bear a spinal ganglion which constitutes the first cell-station of the sensory nerves Internal structures Central canal 中央管 Gray matter Anterior horn (column) 前角（柱） Posterior horn (column)后角（柱） Intermediate zone 中间带 Lateral horn (column) 侧角（柱） Anterior gray commissures 灰质前连合 Posterior gray commissures 灰质后连合 White matter Anterior funiculus 前索 lateral funiculus 外侧索 Posterior funiculus 后索 Anterior white commisure 白质前连合 Posterior horn (column):后角（柱） Marginal layer （缘层） Substantia gelatinosa （胶状质） Nucleus proprius （后角固有核） Nucleus thoracicus（胸核） in segments C8~L3 Intermediate zone　 中间带 Intermediaolateral nucleus （中间外侧核）(lateral horn or column): lies in segments T1~L3, containing sympathetic preganglionic neurons Sacral parasympathetic nucleus（骶副交感核）: lies in segments S2~S4, containing parasympathetic preganglionic neurons Intermediomedial nucleus （中间内侧核） : for sensation of viscera Anterior horn (column): contain motor neurons 　前角（柱） Three kinds of neuron α-motor neuron: larger multipolar neuron, innervates extrafusal fibers of skeletal m., produ