Atypical Thoracic: T1 Flashcards
Which thoracic segments are considered the atypical thoracic?
T1, T9-T12
What is the outline of the vertebral body of T1 from superior view?
Somewhat rectangular with curved anterior margins
What is the appearance of the vertebral body of T1 from the anterior view?
Both sides will appear to be scalloped (indented) between the epiphyseal rims
What is the height pattern of the T1 vertebral body?
The posterior height is greater than the anterior height by one to two millimeters
What is the appearance of the superior surface of the vertebral body of T1?
It is somewhat cup-shaped with elevations at the posterior and lateral margin
What may the elevations on the vertebral body of T1 represent?
Uncinate processes
What is the appearance of the inferior surface of the vertebral body of T1?
Typically flat, lacking anterior and posterior lips characteristic of the cervicals
What joints are identified at the vertebral body of T1?
- vertebral body to the longitudinal ligaments at the epiphyseal rims
- vertebral body to vertebral body via the intervertebral discs
- vertebral body to the head of a rib (costocentral joint)
What joint classifications are identified at the vertebral body of T1?
- fibrous (amphiarthrosis) syndesmosis
- cartilaginous (amphiarthrosis) symphysis
- synovial plane (diarthrosis arthrodia)
- the modified synovial saddle (diarthrosis sellar) is only observed as an anatomical variation
What are examples of fibrous (amphiarthrosis) syndesmosis joints at the T1 vertebral body?
- superior and inferior epiphyseal rims to anterior longitudinal ligament
- superior and inferior epiphyseal rims to posterior longitudinal ligament
What are examples of cartilaginous (amphiarthrosis) symphysis joints at the T1 vertebral body?
- superior epiphyseal rim to intervertebral disc
- inferior epiphyseal rim to intervertebral disc
What are examples of synovial plane (diarthrosis arthrodia) at the T1 vertebral body?
- superior costal facet to articular surface of the head of the first rib
- inferior costal demi-facet to superior articular surface of head of the second rib
How many synovial joints are formed at the vertebral body of T1?`
four normally
How many symphysis joints are formed with the vertebral body of T1?
two
How many syndesmosis joints are formed at the vertebral body of T1?
typically four are identified (as many as eight if the rib articulation is included)
How many joints are formed at the vertebral body of T1?
typically ten (fourteen if the rib ligaments are included)
What is the name given to the joint formed between the vertebral body and rib?
costocentral joint
How many costocentral joints are formed at the vertebral body of T1?
four
What synovial joint surfaces are present on the T1 vertebral body?
- the right and left superior costal facet
- the right and left inferior costal demi-facet
What is the relationship between the vertebral body surface and the rib head surface in the costocentral joints of T1?
- the superior costal facet of the vertebral body will joint completely with the articular surface of the head of the first rib
- the inferior costal demi-facet of the vertebral body will joint with the superior articular surface of the head of the second rib
What is the rib-vertebral body combination at the intervertebral foramen for the eighth cervical nerve?
the superior costal facet of T1 will joint with the articular surface of the head of the first rib
What is the rib-vertebral body combination at the intervertebral foramen for the first thoracic nerve?
- the inferior costal facet of T1 will joint with the superior articular surface of the head of the second rib
- the superior costal demi-facet of T2 will joint with the inferior articular surface of the head of the second rib
What ligament supports the costocentral joint of the first rib?
the costocentral stellate/radiate ligament
What ligaments support the costocentral joint of the second rib?
- the costocentral stellate/radiate ligament
- the costocentral interarticular or intra-articular ligament
The costocentral stellate/radiate ligament will attach to what features?
the head of the rib and the vertebral bodies and intervertebral disc at the costocentral joint
The costocentral stellate/radiate ligament will attach to which segment(s) at the C8 spinal nerve intervertebral foramen?
the vertebral body of C7 and the vertebral body of T1
The costocentral stellate/radiate ligament will attach to which segment(s) at the T1 spinal nerve intervertebral foramen?
the vertebral body of T1 and the vertebral body of T2
What does the costocentral intra-articular or interarticular ligament attach to?
the interarticular or intra-articular crest of the head of the rib and the intervertebral disc
Which muscle(s) is/are attached to the vertebral body of T1?
longus colli
What is the position and direction of the pedicle from the vertebral body of T1?
the pedicle arises from the upper third of the vertebral body and projects posterior and slightly laterally
Which spinal nerve-vertebral notch or incisure combination is present at T1?
- C8 spinal nerve - the superior vertebral notch or incisure of T1
- T1 spinal nerve - the inferior vertebral notch or incisure of T1