Filum terminale | |
---|---|
![]() Cauda equina and filum terminale seen from behind. The dura mater has been opened and spread out, and the arachnoid has been removed. (Filum terminale (internum) labeled at center right.) | |
![]() Sagittal section of vertebral canal to show the lower end of the medulla spinalis and the filum terminale. Li, Lv. First and fifth lumbar vertebra. SII Second sacral vertebra. 1. Dura mater. 2. Lower part of subarachnoid cavity. 3. Lower extremity of medulla spinalis. 4. Filum terminale internum. 5. Filum terminale externum. 6. Attachment of filum terminale to first segment of coccyx. | |
Identifiers | |
TA98 | A14.1.01.401 |
TA2 | 5384, 5414 |
FMA | 83977 |
Anatomical terminology |
The filum terminale ("terminal thread") is a delicate strand of fibrous tissue, about 20 cm in length, extending inferiorly from the apex of the conus medullaris to attach onto the coccyx.[1][2] The filum terminale acts to anchor the spinal cord and spinal meninges inferiorly.[3]
The upper portion of the filum terminale is formed by spinal pia mater within a dilated dural sac, while the lower portion is formed by both pia and dura mater (with the outer dural layer closely adhering to the inner pial component).