Psychology Wiki

Assessment | Biopsychology | Comparative | Cognitive | Developmental | Language | Individual differences | Personality | Philosophy | Social |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |

Biological: Behavioural genetics · Evolutionary psychology · Neuroanatomy · Neurochemistry · Neuroendocrinology · Neuroscience · Psychoneuroimmunology · Physiological Psychology · Psychopharmacology (Index, Outline)

Cauda equina
Cauda equina and filum terminale seen from behind.
Latin '
Gray's subject #208 919
MeSH A08.800.800.720.725.150

The cauda equina is a structure within the lower end of the spinal column of most vertebrates, that consists of nerve roots and rootlets from above. Cauda equina is sometimes considered as an extension of piamater of spinal cord. The space in which the cerebro spinal fluid is present is actually an extension of the sub arachnoid space.

In humans, because the spinal cord stops growing in infancy while the bones of the spine continue growing, the spinal cord in adults ends at about the level of the vertebra L1/L2 , and at birth at L3. Though in adults there is some variation and the cord may end anywhere between vertebrae T12 to L3. Individual spinal nerve roots arise from the spinal cord as they do closer to the head, but as the differential growth occurs the top end of the nerve stays attached to the spinal cord and the lower end of the nerve exits the spinal column at its proper level, this results in a "bundle"-like structure of nerve fibres that extends caudally from the end of the spinal cord, gradually declining in number further down as individual pairs leave the spinal column. At the base of the Cauda Equina, there are approximately 10 fibre pairs, 3-5 lumbar, 5 sacral, and the single coccygeal nerve.


All these roots and rootlets down the vertebral column give the appearance of a horse's tail, which is the meaning of the Latin name cauda equina.

Clinical relevance

Cauda equina is the part of the spinal cord where a spinal tap is performed in order to get a sample of cerebral spinal fluid (CSF) for diagnostic purposes.

See also

External links

Spinal cord

epidural space, dura mater, subdural space, arachnoid mater, subarachnoid space, pia mater, denticulate ligaments, conus medullaris, cauda equina, filum terminale, cervical enlargement, lumbar enlargement, anterior median fissure, dorsal root, dorsal root ganglion, dorsal ramus, ventral root, ventral ramus, sympathetic trunk, gray ramus communicans, white ramus communicans

grey matter: central canal, substantia gelatinosa of Rolando, reticular formation, substantia gelatinosa centralis, interneuron, anterior horn, lateral horn, posterior horn (column of Clarke, dorsal spinocerebellar tract)

white matter: anterior funiculus: descending (anterior corticospinal tract, vestibulospinal fasciculus, tectospinal tract), ascending (anterior spinothalamic tract, anterior proper fasciculus)

lateral funiculus: descending (lateral corticospinal tract, rubrospinal tract, olivospinal tract), ascending dorsal spinocerebellar tract, ventral spinocerebellar tract, spinothalamic tract, lateral spinothalamic tract, anterior spinothalamic tract, spinotectal tract, posterolateral tract, lateral proper fasciculus, medial longitudinal fasciculus

posterior funiculus: fasciculus gracilis, fasciculus cuneatus, posterior proper fasciculus

no:Cauda equina
This page uses Creative Commons Licensed content from Wikipedia (view authors).