Vertebral Column Flashcards
What is the number of vertebrae in a typical adolescent?
33 segments
What is the number of vertebrae in a typical adult?
26 segments
What constitutes the spine?
The 24 presacral segments; the cervical, thoracic and lumbar vertebrae
Which mammals have more than seven cervical vertebrae?
The ant bear and three-toed sloth
Which mammals have less than seven cervical vertebrae?
The manatee and two-toed sloth
What does the term cervical refer to?
The region of the neck
What does the term thoracic refer to?
Breast plate or chest; it referred to the armor bearing region of the torso
What other term is often used to identify the vertebral segments of the chest?
The dorsal segments the dorsals
What does the term lumbar refer to?
The loin; the region between the rib and hip
What does the term sacrum refer to?
The holy bone of holy region
What does the term coccyx refer to?
A cuckoo birds’ bill or cuckoo birds’ beak
What is the length of a typical male spinal column?
About 70 cm or 28 in
What is the length of a typical female spinal column?
About 60 cm or 25 in
What is the length difference between a typical male and typical female spinal column?
About 3 inches
What is the length of the male thoracic region?
About 12 cm or 5 in
What is the length of the male lumbar region?
About 18 cm or 7 in
What is the length of the male sacrum?
About 12 cm or 5 in
Based on the numbers for individual regions of the vertebral column, what is the length of the male spine?
About 58 cm or 23 in
How does the vertebral column participate in skeletal formation?
Ribs are formed from the costal process of the embryonic vertebral template
What levels of the vertebral column specifically accommodate weight-bearing transfer?
S1-S3 at the auricular surface
What is specifically responsible for shape and position of the human frame?
Comparative anterior vs. posterior height of the vertebral body and comparative anterior vs. posterior height of the intervertebral disc
What organ(s) is (are) specifically associated with the horizontal axis of the skull?
The eye and the vestibular apparatus of the inner ear
Invagination of ectoderm along the primitive streak gives rise to what embryonic structure?
Notochord
What is the name given to the mesoderm that will give rise to the vertebral column?
Paraxial mesoderm
Name the areas of cellular differentiation formed within the somite.
Sclerotome, myotome, and dermatome
What are the names of the successive vertebral columns formed during development?
Membranous, cartilaginous, skeletal or osseous
Migration of a somite pair to surround the notochord forms what developmental feature?
The perichordal blastema
The perichordal blastema gives rise to what processes?
Neural processes and costal processes
What is the name of the artery located between adjacent perichordal blastemae?
Intersegmental artery
What forms between the sclerotomites of a perichordal blastema?
The intrasclerotomal fissue (fissue of von Ebner)
The intersclerotomal fissure (fissure von Ebner) gives rise to what developmental feature?
The perichordal disc
The union of a dense caudal sclerotomite and a loose cranial sclerotomite from adjacent perichordal blastemae gives rise to what feature?
The vertebral blastema
What vessel will be identified adjacent to the vertebral blastema?
The segmental artery
When will cartilage first form in the membranous vertebral blastema?
Beginning in the 6th embryonic week
What is the name given to the replacement of mesoderm by cartilage?
Chondrification
How many centers of chrondrification typically appear in the vertebral blastema?
Six… 2 for the centrum, 2 for neural arches, 2 for each transverse process
What is the earliest time that centers of ossification appear in the cartilaginous vertebra?
During the 7th embryonic week
What is the name given to centers of ossification based on time of appearance?
Primary centers appear in utero, secondary centers appear after birth
What is the ratio of primary to secondary centers of ossification for a typical vertebra?
3 primary centers: 5 secondary centers
What are the names of the primary centers of ossification for a typical vertebra?
Centrum centers and neural arch centers
What are the names/locations of the five secondary centers of ossification for a typical vertebra?
Tip of the transverse process, tip of the spinous process, epiphyseal plate centers
What is the range of appearance for secondary centers of ossification of a typical vertebra?
During puberty, typically ages 11-16 years old
What is the general shape of the vertebral body at each region of the spine?
Cervical- rectangular
Thoracic- triangular
Lumbar- reniform
What is the name given to the compact bone at the superior and inferior surfaces of the vertebral body?
Superior epiphyseal rim, inferior epiphyseal rim
What is the name given to the intermediate part of the vertebral arch where the transverse process and articular processes attach?
The lamina- pedicle junction
What is the generic orientation of the pedicle at each region of the spine?
Cervical- posterolateral
Thoracic- posterior, slight lateral
Lumbar- posterior
What ligament will attach to the lamina?
The ligamentum flavum
What is the name given to abnormal bone at the attachment site of the ligamentum flavum?
Para-articular process
What classification of bone will para-articular processes represent?
Accessory bone
What is the name given to the overlap of laminae seen on X-ray?
Shingling
What is the name given to the lamina- pedicle junction at each region of the spine?
Cervical- articular pillar
Thoracic and lumbar- pars interarticularis
What is the name given to the junction of the vertebral arch- spinous process on lateral X-ray?
The spinolaminar junction
What is the generic orientation of the transverse process or transverse apophysis at each region of the spine?
Cervical- anterolateral
Thoracic- posterolateral
Lumbar- lateral
All non-rib-bearing vertebra of the spine retain what equivalent feature?
The costal element
What will cause the transverse process/transverse apophysis to alter its initial direction in the cervical region?
Cervical spinal nerves are pulled forward to form the cervical and brachial nerve plexuses thus remodeling the transverse process to accommodate their new position
What will cause the transverse process/transverse apophysis to alter its initial direction in the thoracic region?
The growth of the lungs remodel the shape of the ribs which in turn push the transverse processes backward
What is the name given to the joint formed between articular facets of a vertebral couple?
The zygapophysis