Week 9 - Osteology of the Spine Flashcards
What are the atypical cervical vertebrae?
The 1st, 2nd, and 7th cervical vertebrae
The 1st is the atlas, the 2nd is the axis, and the 7th is known as the vertebra prominens.
What is a defining feature of the 1st cervical vertebra (atlas)?
It does not possess a body or a spinous process
It has an anterior and posterior arch and lateral masses with articular surfaces.
What unique structure does the 2nd cervical vertebra (axis) have?
A peglike odontoid process (dens) that projects from the superior surface of the body
This represents the fused body of the atlas and axis.
What is the significance of the 7th cervical vertebra?
It has the longest spinous process and is not bifid
It is commonly referred to as the vertebra prominens.
How many thoracic vertebrae are there?
12 vertebrae
From the 2nd to the 8th are referred to as typical thoracic vertebrae.
What is the shape and feature of the body of a typical thoracic vertebra?
Heart shape with 2 demi-facets at its side
This allows articulation with the heads of ribs.
What is the orientation of the spine in a typical thoracic vertebra?
Long, pointed, and directed downward and backward
Describe the vertebral foramen of a typical thoracic vertebra.
Small and circular
What are costal facets and where are they located on a typical thoracic vertebra?
Present on the sides of the bodies and on the transverse processes
They are for articulation with the heads and tubercles of the ribs.
What are the characteristics of a typical lumbar vertebra?
Large and kidney-shaped body, strong pedicles, short laminae, triangular vertebral foramina, long slender transverse processes, short flat quadrangular spinous processes
Articular surfaces of superior processes face medially; inferior processes face laterally.
True or False: Lumbar vertebrae have facets for articulation with ribs.
False
Lumbar vertebrae do not have facets for ribs and no foramina in the transverse processes.
What is unique about T1 in the thoracic vertebrae?
It has a full facet for the first rib
What is the characteristic of T9 in the thoracic vertebrae?
It often articulates only with its own rib and lacks inferior demifacet
What type of facet do T10 to T12 have?
A single facet
Which thoracic vertebrae lack costal facets?
T11 and T12
What is the term for the radiographic feature seen in ankylosing spondylitis that indicates vertebral body fusion?
Bamboo spine
Bamboo spine results from the ossification of the outer fibers of the annulus fibrosus of intervertebral discs, forming marginal syndesmophytes.
What are the articulations called between the superior and inferior articular facets of vertebrae?
Zygapophyseal joints
These joints contribute to range of motion and decrease weight-bearing stress.
What is the condition characterized by a defect or fracture of one or both wing-shaped parts of a vertebra?
Spondylolysis
This condition can lead to vertebrae slipping either backward or forward.
Define spondylolisthesis.
Slipping of a vertebra that occurs in relation to the vertebra below it
It is most common in the lumbar spine and can cause pain when walking or standing.
What is the space where spinal nerve roots exit the vertebral column called?
Intervertebral foramen
The size can vary due to placement, pathology, and posture.
How many intervertebral discs are present in the human spine?
23 intervertebral discs
No disc exists between the skull and C1 or between C1 and C2.
What are the primary functions of intervertebral discs?
- Shock absorbers in walking, jumping, running
- Allow spine to bend
Discs flatten out and bulge at points of compression.
What percentage of the height of the vertebral column is made up by intervertebral discs?
25%
Aging leads to permanent dehydration of discs, decreasing range of motion.
What common lower back problems can cause pain in the L4-L5 segment?
- L4-L5 disc herniation
- L4-L5 degenerative disc disease
- Spondylolisthesis
These conditions arise due to the weight these segments carry and their range of motion.
What is kyphosis?
An abnormally excessive convex curvature of the spine
It causes the top of the back to appear more rounded and can lead to severe pain.
What are the conditions that can cause kyphosis?
- Osteoporosis
- Spondylosis
- Spina bifida
- Paget’s disease
- Neurofibromatosis
- Muscular dystrophy
- Tuberculosis
These conditions can lead to deformities and complications in spinal structure.
What is the abnormal inward concave curving of the cervical and lumbar regions of the spine called?
Lordosis
This condition can result in discomfort and postural issues.
What is scoliosis?
A sideways curvature of the spine
It often occurs during the growth spurt just before puberty and can have unknown causes.
What are the three main types of spina bifida?
- Spina bifida occulta
- Meningocele
- Myelomeningocele
Spina bifida is a birth defect where there is incomplete closing of the backbone.
What is a common symptom of myelomeningocele, the most severe form of spina bifida?
Poor ability to walk
Associated problems include bladder or bowel control issues and hydrocephalus.
True or False: The first X-ray in the text shows a pars fracture in the fifth lumbar vertebra.
True
The second X-ray shows spondylolisthesis in the same vertebra.
What are the clinical manifestations of cervical herniated nucleus pulposus (HNP) at the C5-C6 level?
- Pain - neck, shoulder, anterior upper arm to thumb
- Absent/diminished reflexes
- Motor changes - paresis or paralysis
- Sensory - paresthesia or pain
- Muscle spasms
These manifestations depend on which nerve root or spinal nerve is being compressed.
