spine cord课件

1、The Nervous System山东大学医学院山东大学医学院 解剖教研室解剖教研室李振华李振华Organizations nCentral nervous system (CNS) 中枢神经系统中枢神经系统nPeripheral nervous system (PNS) 周围神经系统周围神经系统Major Division of the Central Nervous System (CNS)nBrain 脑脑 qTelencephalon 端脑端脑qDiencephalon 间脑间脑qCerebellum 小脑小脑qBrain stem 脑干脑干 nMidbrain 中脑中脑nPons

2、脑桥脑桥nMedulla oblongata 延髓延髓nSpinal cord 脊髓脊髓Major Division of the Peripheral Nervous System (PNS)nCranial nerves (12 pairs) 脑神经脑神经nSpinal nerves (31 pairs) 脊神经脊神经nVisceral nerves内脏神经内脏神经qVisceral sensory nerveqVisceral motor nervenSympathetic part 交感神经交感神经n Parasympathetic part 副交感神经副交感神经Cellular Or

3、ganizationnNeuron 神经元神经元 qCell body 胞体胞体qAxon 轴突轴突qDendrites 树突树突 n Neuroglia glial cell胶质细胞胶质细胞 Classification of NeuronsStructural classificationnBipolar neuron 双极神经元双极神经元 qhas an axon and a dendritenPseudounipolar neuron 假单极神经元假单极神经元 qhas a central branch and a peripheral branchnMultipolar neuron

4、 多极神经元多极神经元qhas an axon and two or more dendritesClassification of NeuronsFunctional classificationnSensory (afferent) neuron 感觉神经元感觉神经元nMotor (efferent) neuron 运动神经元运动神经元nAssociation neuron 联络神经元联络神经元nReflex: a reaction of the organism by the nervous system in response to a stimulusnReflex arc: has

5、 5 basic components Receptor Sensory neurons CNS Motor neurons Effector Reflex and Reflex ArcReflex and Reflex ArcBasic Terminology in Nervous SystemIn the CNSnGray matter 灰质灰质: collection of nerve cell bodies and their dendrites, gray color during fresh conditionnCortex 皮质皮质: the outermost layer of

6、 gray matter in cerebrum and cerebellumnWhite matter 白质白质: collection of nerve fibers, white color during fresh conditionnMedulla 髓质髓质: a central core of white matter beneath cortex of cerebrum and cerebellumBasic Terminology in Nervous SystemIn the CNSnNucleus 神经核神经核: a collection ( group ) of cell

7、 bodies which have the same shape and functionnFasciculus ( tract ) 纤维束纤维束: a bundle of nerve fibers which have the same origin, termination, pathway and functionnReticular formation 网状结构网状结构: an admixture of cross-crossing fibers with larger or smaller groups of nerve cells occupying the meshesBasi

8、c Terminology in Nervous SystemIn the PNSnGanglion 神经节神经节: a collection of neuronal cell bodies outside the CNSnNerve 神经神经: a bundle of nerve fibers held together by connective tissue sheathThe Spinal Cord 脊髓脊髓学习方法学习方法看断面，想立体，上下串联。看断面，想立体，上下串联。Position of the Spinal Cord nLies in vertebral canalnCon

9、tinuous above with medulla oblongata at level of foramen magnum nEnds below at the lower border of L1 in the adult; at birth the cord ends at level of L3nA long cylindrical structure and slightly flattened anteroposteriorlynTwo enlargementsqCervical enlargement 颈膨大颈膨大 corresponds to the C4 to the T1

10、 segmentsqLumbosacral enlargement 腰骶膨大腰骶膨大 corresponds to the L2 to the S3 segmentsnConus medullaris 脊髓圆锥脊髓圆锥nFilum terminale 终丝终丝nCauda equina 马尾马尾 External Features of Spinal CordExternal Features of Spinal CordFissure and sulcinAnterior median fissure 前正中裂前正中裂nPosterior median sulcus 后正中沟后正中沟qPos

11、terior median septum 后正中隔后正中隔nAnterolateral sulcus 前外侧沟前外侧沟 anterior (motor) roots emerge serially nPosterolateral sulcus 后外侧沟后外侧沟 posterior (sensory) roots enter spinal cord, each bear a spinal ganglion which constitutes the first cell-station of the sensory nervesSegments of Spinal CordnA portion

12、of the cord that gives rise to a pair of spinal nerve constitutes a segment. nThere are 31 segments 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygealRelationship of spinal Cord Segments to Vertebral NumbersSpinal segmentsVertebral levels (spines)Upper cervical region (C1C4)Lie opposite the corres

13、ponding vertebraeLower cervical and upper thoracic region (C5T4)One lower in number than corresponding vertebraeMiddle thoracic region (T5T8)Two lower in number than corresponding vertebraeLower thoracic region (T9T12)Three lower in number than corresponding vertebraeLumber segmentsT10T12Sacral and

14、coccygeal segmentsL1Relationship of spinal Cord Segments to Vertebral NumbersSpinal segmentsVertebral levels (spines)Upper cervical region (C1C4)= C1 C4Lower cervical and upper thoracic region (C5T4)1 = C4 T3Middle thoracic region (T5T8)2 = T3 T6Lower thoracic region (T9T12)3 = T6 T9Lumber segments=

15、 T10 T12Sacral and coccygeal segments= L1Structure of Spinal Cord nGray matter 灰质灰质nWhite matter 白质白质nCentral canal 中央管中央管 Gray Matter of Spinal Cord nAnterior horn (column) 前角（柱）前角（柱）nPosterior horn (column)后角（柱）后角（柱）nLateral horn (column) 侧角（柱）侧角（柱） is present in the thoracic and upper lumber segm

16、ents of the cord (T1-L3) nIntermediate zone 中间带中间带nAnterior gray commissures 灰质前连合灰质前连合nPosterior gray commissures 灰质后连合灰质后连合Gray Matter of Spinal CordPosterior horn (column):nMarginal layer 缘层缘层 （后角边缘核）（后角边缘核）nSubstantia gelatinosa 胶状质胶状质qSituated at the apex of posterior horn throughout the length

17、 of spinal cordqConcerns the sensations of pain and temperaturenNucleus proprius 后角固有核后角固有核qSituated anterior to the substantia gelationnosa throughout the length of spinal cordqReceives fibers that are associated with the sensesnNucleus thoracicus 胸核胸核 qSituated at the base of posterior horn and ex

18、tending from segments C8L3qAssociated with proprioceptive endingsGray Matter of Spinal CordIntermediate zonenIntermediaolateral nucleus 中间外侧核中间外侧核 (lateral horn)qExtents from segments T1L3, qContaining sympathetic preganglionic neuronsnSacral parasympathetic nucleus 骶副交感核骶副交感核qExtents from segments

19、S2S4, qContaining parasympathetic preganglionic neuronsnIntermediomedial nucleus 中间内侧核中间内侧核 qThroughout the length of spinal cordqAssociated with receiving viscera afferent informationGray Matter of Spinal Cord Anterior horn (column): nTwo kinds of motor neurons q-motor neuron: large multipolar neur

20、on, innervates skeletal muscles, producing contraction of musclesq-motor neuron: smaller multipolar neuron, innervates intrafusal muscle fibers of neuromuscular spindles, regulating muscular tonusnInterneuron Renshaws cell: negative feedback mechanismnTwo groups of nucleiqMedial nuclear group: prese

21、nt in most segments of spinal cord, innervating axial musclesqLateral nuclear group: present only in cervical and lumbosacral enlargements, innervating limb muscles Rexeds lamina 板层板层nPosterior horn is formed by lamina to ； nIntermediate zone corresponding to lamina ；nAnterior horn is composed lamin

22、ae and ；nlamina is the gray matter surrounding the central canal.Important Subdivision of Spinal Cord Gray MatterRegion LaminaNucleusPosterior hornMarginal layerSubstantia gelatinosa, Nucleus propriusIntermediate zoneNucleus thoracicus (C8L3)Intermediolateral nucleus (T1L3)Sacral parasympathetic nuc

23、leus (S2S4)Intermediomedial nucleus Anterior hornMotor neuron White Matter of Spinal Cord White matter contains three kinds of fibers: ascending, descending, and fasciculus propriusAnterior funiculus 前索前索Lateral funiculus外侧索外侧索Posterior funiculus后索后索Anterior white commissure白质前连合白质前连合Ascending Tract

24、sFasciculus gracilis（薄束）（薄束）Fasciculus cuneatus （楔束）（楔束） Posterior spinocerebellar tract（脊髓小脑后束）（脊髓小脑后束）Anterior spinocerebellar tract（脊髓小脑前束）（脊髓小脑前束）Spinothalamic tract（脊髓丘脑束）（脊髓丘脑束）Fasciculus gracilisFasciculus cuneatusSpinothalamic tractAscending tractsTract Site of originFuniculus TerminationFun

25、ction Fasciculus gracilisSpinal ganglia below segment T5Posterior Gracile nucleus Conscious proprioceptive (vibratory sense, and muscle joint sense) and fine touch sensation of trunk and limbsFasciculus cuneatusSpinal ganglia above segment T4Cuneate nucleusPosterior spinocerebellarHomolateral nucleu

26、s thoracicusLateral Cerebellum Unconscious proprioception from lower limb and lower portion of trunkAnterior spinocerebellarContralateral Laminae Spinothalamic Laminae , Lateral and anteriorDorsal thalamusPain, temperature and crude touch sensation of trunk and limbs Descending Tracts Lateral corticospinal tract（皮质脊髓侧束）（皮质脊髓侧束）Anterior corticospinal tract （皮质脊髓前束）（皮质脊髓前束）Rubrospinal tract （红核脊髓束）（红核脊髓束）Vestibulospinal tract（前庭脊髓束）（前庭脊髓束）Reticulospinal tract（网状脊髓束）（网状脊髓束）Medi