Structure of the Nervous System Anatomy Tutorials

Region: Spine

Lamina

Lamina The structure indicated is the lamina of the vertebra. The typical vertebra consists of the following features: Vertebral body Vertebral arch (neural arch) consisting of lamina and pedicle Spinous process Transverse process Vertebral foramen (collectively form vertebral canal) Superior and inferior articular processes Superior and inferior vertebral notches The vertebral arch is formed from two pedicles and two laminae. The pedicles attach on either side to the posterolateral aspects of the vertebral body and unite posteriorly with the laminae which complete the vertebral arch. The laminae provide attachment for the ligamentum flavum, which connect adjacent laminae along the length …

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lamina

Vertebral Body

Vertebral Body The structure indicated is the vertebral body. There are 33 vertebrae which make up the spinal column: 7 cervical 12 thoracic 5 lumbar 5 fused sacral vertebrae 3-4 fused coccygeal vertebrae The typical vertebra consists of the following features: Vertebral body Vertebral arch (neural arch) consisting of lamina and pedicle Spinous process Transverse process Vertebral foramen (collectively form vertebral canal) Superior and inferior articular processes Superior and inferior vertebral notches The vertebral body is the largest component of the vertebra. Between adjacent vertebrae within the spinal cord, the vertebral bodies are joined by intervertebral discs which form fibrocartilaginous …

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vertebral body

Superior Articular Process

Superior Articular Process The structure indicated is the superior articular process. There are 33 vertebrae which make up the spinal column: 7 cervical 12 thoracic 5 lumbar 5 fused sacral vertebrae 3-4 fused coccygeal vertebrae The typical vertebra consists of the following features: Vertebral body Vertebral arch (neural arch) consisting of lamina and pedicle Spinous process Transverse process Vertebral foramen (collectively form vertebral canal) Superior and inferior articular processes Superior and inferior vertebral notches The superior articular process articulates with the inferior articular process of the vertebrae above. These articulations are known as zyapophysial joints. The articular processes arise from …

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superior articular process

Spinothalamic Tract

Spinothalamic Tract This diagram illustrates the spinothalamic tract (also known as the anterolateral system/ventrolateral system). The spinothalamic tract is one of the ascending sensory tracts which conveys sensory information from the periphery to the central processing systems. There are three main ascending (afferent) pathways which convey sensory information: Dorsal column medial lemniscus system Spinocerebellar tracts Spinothalamic tracts (anterolateral system) The spinothalamic tract is responsible for conveying the modalities of crude touch, pressure, pain and temperature. The tract is comprised of a three neurone sequence, which terminates in the somatosensory cortex of the postcentral gyrus: First order neurone: information carried from …

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Spinothalamic Tract

Gray Ramus Communicans

Gray Ramus Communicans The structure indicated is the gray ramus communicans (known collectively as the gray rami communicantes). The spinal nerves at each level receive this branch, the gray ramus communicans, conveying postganglionic nerve fibres from the sympathetic nervous system. In the same picture, parallel to the gray ramus communicans, the branch which conveys the preganglionic sympathetic fibres into the paravertebral sympathetic ganglia is known as the white ramus communicans. The preganglionic nerve fibre which passes through the white ramus communicans has three potential outcomes: Synapse in the paravertebral ganglion. Travel up or down a level in the sympathetic chain …

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Gray Ramus Communicans

Anulus Fibrosus

Anulus Fibrosus The structure indicated is the anulus fibrosus of the intervertebral disc. Intervertebral discs are found between adjacent vertebral bodies in the spinal column. Intervertebral discs are one of two major joint types found in the vertebrae, the other type being synovial joints between the articular processes. The symphyses between the vertebral bodies consists of hyaline cartilage which lines the vertebral body, and an intervertebral disc which is sandwiched between the two adjacent intervertebral bodies to form this fibrocartilaginous joint. The intervertebral disc consist of Anulus fibrosus (outer component) Nucleus pulposus (inner component) The anulus fibrosus forms the outer …

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Anulus Fibrosus