- Column of Clarke
Name = PAGENAME
Latin = nucleus thoracicus posterior, nucleus dorsalis
GraySubject = 185
GrayPage = 758
Caption = Diagram showing a few of the connections of afferent (sensory) fibers of the
posterior rootwith the efferent fibersfrom the ventral column and with the various long ascending fasciculi. (Dorsal nucleus labeled at center right.)
Caption2 = Schematic of spinal cord grey matter showing location of the Dorsal Nucleus
DorlandsPre = n_11
DorlandsSuf = 12583750
Clarke's column (column of Clarke, dorsal nucleus, posterior thoracic nucleus) is a group of
interneurons found in Lamina VII, also known as the intermediate zone, of the spinal cord.
It occupies the medial part of the base of the
posterior columnand appears on the transverse section as a well-defined oval area.
It begins below at the level of the second or third
lumbar nerve, and reaches its maximum size opposite the twelfth thoracic nerve. Above the level of the ninth thoracic nerve its size diminishes, and the column ends opposite the last cervical or first thoracic nerve.
It is represented, however, in the other regions by scattered cells, which become aggregated to form a cervical nucleus opposite the third cervical nerve, and a sacral nucleus in the middle and lower part of the sacral region.
Nerve cells in Clarke’s column are most abundant between the lower thoracic and upper lumbar segments. Cell bodies are of medium size and oval- or pyriform-shape. Some cells can be as large as anterior horn cells; the nuclei of these larger cells are often found on the periphery of the cell.
Clarke’s column is a major relay center for unconscious
proprioception. Sensory information for muscle spindles and tendon organs synapses onto dorsal root ganglion, which in turn synapses onto Clarke’s column. From Clarke’s column, information continues rostrally until it reaches the cerebellar cortex. This relay pathway is generally known as the spinocerebellar tract.
It is named for
Jacob Augustus Lockhart Clarke. [WhoNamedIt|synd|2143] [J. A. L. Clarke. Researches into the structure of the spinal cord. Philosophical Transactions of the Royal Society of London, 1851, 141: 607-621.]
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