| Central canal of spinal cord | |
|---|---|
 Cross-section through cervical spinal cord. | |
 | |
| Details | |
| Location | Centre of thespinal cord |
| Identifiers | |
| Latin | canalis centralis medullae spinalis |
| TA98 | A14.1.02.019 |
| TA2 | 6127 |
| FMA | 78497 |
| Anatomical terminology | |
Thecentral canal (also known asspinal foramen orependymal canal) is thecerebrospinal fluid-filled space that runs through thespinal cord.[1] The central canal lies below and is connected to theventricular system of thebrain, from which it receives cerebrospinal fluid, and shares the sameependymal lining. The central canal helps to transport nutrients to the spinal cord as well as protect it by cushioning the impact of a force when the spine is affected.
The central canal represents the adult remainder of the central cavity of theneural tube. It generally occludes (closes off) with age.[2]
The central canal below at theventricular system of thebrain, beginning at a region called theobex where thefourth ventricle, a cavity present in the brainstem, narrows.
The central canal is located in theanterior third of the spinal cord in thecervical andthoracic regions. In thelumbar spine it enlarges and is located more centrally. At theconus medullaris, where the spinal cord tapers, it is located moreposteriorly.
Theterminal ventricle (ventriculus terminalis,fifth ventricle orampulla caudalis) is the widest part of the central canal of thespinal cord that is located at or near theconus medullaris.[3] It was described by Stilling in 1859 and Krause in 1875.[4] Krause introduced the term fifth ventricle after observation of normalependymal cells.[4] The central canal expands as a fusiform terminal ventricle, and approximately 8–10 mm in length in the conus medullaris (or conus terminalis).[5] Although the terminal ventricle is visible in the fetus and children, it is usually absent in adults.[6]
Sometimes, the terminal ventricle is observed byMRI orultrasound in children less than 5 years old.[7]
The central canal shares the sameependymal lining as the ventricular system of the brain.
The canal is lined byciliated,column-shaped cells, outside of which is a band of gelatinous substance, called thesubstantia gelatinosa of Rolando alsosubstantia gelatinosa centralis orcentral gelatinous substance of spinal cord. This gelatinous substance consists mainly ofneuroglia, but contains a few nerve cells and fibers; it is traversed by processes from the deep ends of the columnar ciliated cells which line the central canal.
The central canal represents the adult remainder of the central cavity of theneural tube. It generally occludes (closes off) with age.[2]
The central canal carriescerebrospinal fluid (CSF), which it receives from theventricular system of the brain. The central canal helps to transport nutrients to the spinal cord as well as protect it by cushioning the impact of a force when the spine is affected.
Syringomyelia is a disease caused by the blockage of the central canal. Blockage of the central canal usually occurs at the lower cervical and upper thoracic levels. This typically damageswhite matter fibers that cross inanterior white commissure, leading to the loss of temperature, pain, and motor function at the affected levels on side opposite to the damage.
Other relevant conditions include:
In some cases, the terminal ventricle may cause clinical symptoms due to its expansion.
This article incorporates text in thepublic domain frompage 753 of the 20th edition ofGray's Anatomy(1918)
Tomsick T, Peak E, Wang L: Fluid-Signal Structures in the Cervical Spinal Cord on MRI: Anterior Median Fissure vs. Central Canal. AJNR 2017; 38:840–45
Tomsick T, Wang L, Zuccarello M, Ringer AJ. Fluid-signal structures in the cervical spinal cord on MRI in Chiari patients: Central canal or anterior median fissure? AJNR Am J Neuroradiol. 2021 Apr;42(4):801-806. doi: 10.3174/ajnr.A7046. Epub 2021 Mar 11.PMID: 33707286
