Intervertebral Foramen Flashcards
What determines the length of the intervertebral foramen?
The width of the pedicle
What is the average height of the intervertebral foramen?
About 13 mm
What percent of total vertebral column length does “true” intervertebral foramina height from C2-S1 equal?
40%
What percent of total vertebral column length does all intervertebral foramina height from occiput-Co1 equal?
53%
What are the generic contents of the intervertebral foramen?
Neural tissue, connective tissue, vascular tissue, lymphatic tissue
What is the percent of neural tissue in the intervertebral foramen?
From 8 to 50 percent
What are 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?
The 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 ligament lies next to the anterior internal vertebral venous plexus?
The posterior longitudinal ligament
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 type(s) of connective tissue will be present in the intervertebral foramen?
Adipose tissue and loose areolar connective tissue
What parts of the cervical vertebra will modify the intervertebral foramen?
The lateral groove and uncinate process
What happens to cervical nerve roots between their origin from the spinal cord and exit from the intervertebral foramen?
The descend along the spinal cord
What is the relationship between aging and cervical spine nerve root characteristics?
The 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?
The cross-sectional area diminishes after age 50
What are the specific attachment sites for a cervical spinal nerve?
The sulcus for the ventral primary ramus on the costotransverse bar and the vertebral artery
What contributes to the anterior boundary of the thoracic intervertebral foramen?
The costocentral joint
Which are the largest spinal nerves?
L5 and S1 spinal nerves
What increases the length of the intervertebral foramen at L5?
The lumbosacral tunnel
What forms the lumbosacral tunnel?
The lumbosacral ligament, transverse process of L5 and sacral ala
What condition is the result of encroachment on the L5 spinal nerve?
The far out syndrome
What is the relationship between intervertebral disc herniation and lumbar spinal nerves?
The 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?
A completely osseous boundary exists
What is more likely the cause of nerve irritation at 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?
The 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 and Co1 nerve
What are some examples of destructive lesions of the vertebral artery?
Tuberculosis, hemangiomas, osteoporosis
What may reduce the impact of intervertebral disc loss of integrity on the intervertebral foramen in the cervical and thoracic spine?
The joint of Luschka in the cervicals, the costocentral joint in the thoracics
What are examples of osteophyte formation that influence the intervertebral foramen?
The bony spurs of the vertebral body and para-articular processes on the lamina
What are examples of acquired alterations of the spinal curves identified in class?
Obesity, pregnancy and the use of heavy backpacks
What is the recommended weight of a backpack compared to individual weight for the developing spine?
Backpack weight should not exceed 10% individual body weight
