Intervertebral Foramen Flashcards
What determines the length of the intervertebral foramen?
Width of pedicle
What is the average height of the intervertebral foramen?
About 13mm
What percentage of total vertebral column length does “true” intervertebral foramina height from C2-S1 equal?
40%
What are the generic contents of the intervetebral foramen?
Neural tissue
Connective tissue
Vascular tissue
Lymphatic tissue
What are the medullary feeder arteries?
Enlarged radicular arteries which join the arterial vasa corona to provide blood for the spinal cord
What is the name of the largest medullary feeder artery?
Artery of Adamkiewicz or the arteria radicalis magna anterior
What are the characteristics of the Artery of Adamkiewicz?
It is a left side, anterior medullary feeder artery, located in the T9/T10 intervertebral foramen, and the primary vascular supply to the lumbar enlargement
What venous plexus lies next to the posterior longitudinal ligament?
Anterior internal vertebral venous plexus
What will the intervertebral veins drain into?
External vertebral venous plexus or Batson’s plexus
What is a unique histological feature of the veins of the vertebral column?
They appear to lack valves
What size lymphatic vessels lie in the intervertebral foramen?
Medium sized lymphatics
What types of connective tissue will be present in the intervertebral foramen?
Adipose tissue
Loose areolar connective tissue
What parts of the cervical vertebra will modify the intervertebral foramen?
Lateral groove
Uncinate process
What happens to the cervical nerve roots between their origin from the spinal cord and exit from the intervertebral foramen?
They descend along the spinal cord
What is the relationship between aging and cervical spine nerve root characteristics?
Length of the nerve root increases as it descends from its apparent origin on the spinal cord, but the cross-sectional area of the nerve root decreases
What is the relationship between aging and cervical spine intervertebral foramen size?
Cross-sectional area diminishes after age 50
What are the specific attachment sites for a cervical spinal nerve?
Sulcus for the ventral primary ramus on the costotransverse bar & the vertebral artery
What contributes to the anterior boundary of the thoracic intervertebral foramen?
Costocentral joint
Which are the largest spinal nerves?
L5 and S1 spinal nerves
What increases the length of the intervertebral foramen at L5?
Lumbosacral tunnel
What forms the lumbosacral tunnel?
Lumbosacral ligament
Transverse process of L5
Sacral ala
What condition is the result of encroachment on the L5 spinal nerve?
Far out syndrome
What ligament may contribute to the loss of size in the lumbar intervertebral foramen?
Transforaminal ligament
What is the relationship between intervertebral disc herniation and lumbar spinal nerves?
Intervertebral disc above the intervertebral foramen is usually the source of damage
What is unusual about the sacral intervertebral foramen compared to other intervertebral foramina?
Completely osseous boundary exists
What is more likely the cause of nerve irritation of the sacral intervertebral foramen?
The tilt or position of the entire sacrum relative to the pelvis
What is the relationship of lumbar nerve root size to intervertebral foramen size above L4?
Nerve root size will account for less than 22% of the available size
What is unique about the relationship of spinal nerve to intervertebral foramen at S5-Co1?
There are two nerves present, S5 nerve & Co1 nerve
What are some examples of destructive lesions of the vertebral body?
Tuberculosis
Hemangiomas
Osteoporosis
What are examples of osteophyte formation that influence the intervertebral foramen?
Bony spurs of the vertebral body
Para-articular processes on the lamina
What are examples of acquired alterations of the spinal curves identified in class?
Obesity
Pregnancy
Use of heavy backpacks
