Axial Skeleton: Joints of Vertebral Bodies/Arches Flashcards
What is Symphysis?
- The binding tissue is a fibrocartilaginous disc
- Adjacent vertebral bodies bound together by intervertebral disc
- Contains the Anterior and Posterior longitudinal ligament
What are the characteristics of the Intervertebral discs?
- From C2 to L5 vertebrae
- Increases in thickness as it descends (range of movement depends of the size)
- Thicker in the cervical and lumbar vertebrae due to the Secondary curvatures
*Resist forces of compression and torsion
What is Anulus fibrosus?
- Outer layer of the Intervertebral disc
- Concentric lamellae (layers) of fibrocartilage
- Contains collagen fibers (Type 1)
- Attaches to the smooth epiphysial rim around the edges of the superior and inferior surfaces of adult vertebral bodies
*Becomes less vascularized toward the center
What is Nucleus pulposus?
- The inner layer of the Intervertebral disc
- Composed of:
a. Type 2 collagen (jelly-like)
b. Proteoglycan (attract a lot of water)
c. Hyaluronic acid
*Attracts water molecules, hydrating the nucleus pulposus by osmotic swelling pressure effect
What is collagen fibers in vertebral bodies?
- Provides a strong bond between adjacent vertebrae
2. Allows limited rotation between vertebrae
What is Epiphyseal rim?
- Are formed by the fused anular epiphyses
What is Anular epiphyses?
- Zone from which the vertebral bodies grow in height
- Are secondary ossification centers
- Appear during adolescence; fused by 25 years old
What is the function of Nucleus Pulposus?
- Responsible for flexibility and resilience of IV disc/vertebral column
* Water content declines over time due to the gradual loss of proteoglycans
* Check height of a patient before 10am because there is a reduction in pressure borne of the disc during the day
How does Nucleus pulposus receive nourishment?
- Avascular
2. Receives nourishment by diffusion from blood vessels at the periphery of the anulus fibrosus and vertebral body
What are 2 joints between C3 and
C7 on their posterolateral margin?
- Uncovertebral (frequent site of spur formation that may cause neck pain)
- Neurocentral (Luschka’s joints)
What is the Uncovertebral joint?
- Between C3 and C7
- Have Uncinate processes (bony elevations on the superior margin of the cervical vertebrae)
- Sometimes considered a synovial joint; others believe it is a result from the degenerative process throughout age
- Bone spur formation occur with advance age, which cause neck pain
What is an Uncinate processes?
- Bony elevation on the superior margin of cervical vertebrae (C3 to C7)
- Allow flexion and extension in the cervical vertebral column
- Limits lateral flexion in the cervical VC
- Important landmark in surgery because vertebral arteries lie lateral of the uncovertebral joint
What is osteophytes?
- Sites of bone spur formation
2. Causes neck pain
What is the Anterior Longitudinal Ligament?
- Connects the anterolateral aspects of the vertebral bodies and IV discs
- Extends from the pelvic surface of the sacrum to the anterior tubercle of vertebra C1 and the occipital bone anterior to the foramen magnum
- Prevents hyperextension of the VC, maintaining stability of the joints between the vertebral bodies
*Upper most part forms the Anterior atlanto-axial membrane (AAA) and Anterior atlanto-occipital membrane (AAO)
What is the Posterior Longitudinal Ligament?
- Narrower and weaker than the anterior longitudinal ligament
- Located within the vertebral canal along the posterior surfaces of the vertebral bodies
- Extends from the sacrum to C2 vertebrae where it becomes Tectorial membrane (TM)
- Weakly prevents hyperflexion
- Helps prevent posterior herniation of the nucleus pulposus
What is the Tectorial membrane (TM)?
- At the C2 vertebrae, which the top part of the posterior longitudinal ligament
What are 3 parts of the vertebral arches?
- Laminae
- Transverse processes
- Spinous processes
- Are connected by ligaments including:
a. Ligamenta flava
b. Interspinous and supraspinous ligaments
c. Intertransverse ligaments
d. Ligamentum nuchae
What is the Zygapophyseal Joints?
- Joints between the superior and inferior articular processes of adjacent vertebrae
- Each joint is surrounded by a thin joint capsule (Allows gliding movement)
- Range of movement depends on the size of the IV disc
- Seen as synovial joints
What is the Ligamenta flava?
- Connect laminae of adjacent vertebrae, from C2 to S1
- Consist of a yellow elastic tissue (thicker in the lumbar region; thinner in the cervical region)
- Becomes the Posterior atlanto-axial membrane and Posterior atlanto-occipital membrane
What is the function of the ligamenta flava?
- Prevent separation of the laminae by limiting abrupt, sudden, excessive hyperflexion, which prevents injury on the IV discs
- Help preserve the normal curvatures of the VC and upright posture
- Assist with straightening of the column after flexing
*C1 (atlas) doesn’t have a lamina, which is why the ligamenta flava starts at C2
What is the Interspinous ligaments?
- Connects adjoining spinous processes (in between the spinous processes)
- Thin spinous tissue
What is the Supraspinous ligament?
- Strong fibrous cord that connects the tips of the spinous process from C7 to the sacrum
- Merges superiorly with the ligamentum nuchae
What is the Ligamentum nuchae?
- A strong fibroelastic membrane that forms a median band
- Extends from the external occipital protuberance and posterior border of the foramen magnum to the spinous processes of the cervical vertebrae
- Site of muscular attachment for muscles that attach to the spinous processes
*Strong median ligament of the neck
What is the Intertransverse ligaments?
- Connect adjacent transverse processes
What are the boundaries of the Intervertebral foramina?(What makes up the vertebral foramen?)
- Vertebral bodies and IV discs form the anterior boundary
- Superior and Inferior vertebral notches form the top and bottom of the vertebral foramen
- Zygopophysial joints and the Ligamenta Flava create the posterior boundary
What Spondylolysis?
- Fracture of the pars interarticularis
* Pars interarticularis is part of the lamina (Connects the superior and inferior articular process)
* In x-ray: The pars interarticularis (neck) looks like a dog with a collar around its neck. (scotty dog)
What causes Spondylolysis?
- Genetics- When the vertebral body and vertebral arches fail to fusion during development
- Repeated trauma or hyperextension of lumbar spine (gymnasts, weight lifter, tennis players)
- Degenerative disease- Arthritic changes in vertebral joints and cartilage degeneration
What is Spondylolisthesis?
- A vertebra slips forward or backward compared to the next vertebra
