Which thoracic segments are considered the typical thoracics?
T2-T8 segments
What features will allow discrimination between T2-T4 and T5-T8 segmental groups?
- vertebral body
- transverse process
- articular process
- spinous process
What is the outline of the vertebral body of a typical thoracic from superior view?
triangular
On cranial view, what is the outline of the vertebral body for the T2-T4 group?
the vertebral body will have bilaterally convex sides
On cranial view, what is the outline for the vertebral body for the T5-T8 group?
the left side of the vertebral body will be flattened, the right side convex
What is the appearance of the vertebral body from the anterior view for T2-T4?
both sides will appear to be scalloped (indented) between the epiphyseal rims
What is the appearance of the vertebral body from the anterior view for T5-T8?
the left side will appear to be less scalloped (indented) between between the epiphyseal rims compared to the right side
What is the cause for the flattening of the left side of the vertebral body on T5-T8?
The descending thoracic aorta will come to lie on the left side of the vertebral body in this region and prevent the epiphyseal plate cartilage from deforming as much on the right side. When the epiphyseal plates ossify, the epiphyseal rim will not be pushed out as far on the left so that side of the vertebral body appears to be less scalloped.
What is the name given to the left side appearance of the vertebral body of T5-T8?
the aortic impression
What is the height pattern of the typical thoracic vertebral body?
the posterior height is greater than the anterior height by one to two millimeters
What is the height pattern of intervertebral discs in the typical thoracic region?
the intervertebral discs are rather planar or flat with no apparent height difference between anterior and posterior heights
What is the principal cause of the posterior curve of the thoracic spine?
the vertebral body height differences
In terms of the anterior-posterior curves of the vertebral column, what direction will the thoracic spine face?
posterior
What is another way of naming a posterior curve pattern?
a kyphotic curve
What joints are identified at the vertebral body of a typical thoracic?
- vertebral body to anterior longitudinal ligament at the epiphyseal rims
- vertebral body to posterior longitudinal ligament at the epiphyseal rims
- vertebral body to vertebral body via the intervertebral discs
- vertebral body to capitulum of a rib (costocentral joint)
What joint classifications are identified at the vertebral body of a typical thoracic?
- fibrous (amphiarthrosis) syndesmosis
- cartilaginous (amphiarthrosis) symphysis
- synovial plane (diarthrosis arthrodia)
What are the examples of fibrous (amphiarthrosis) syndesmosis joints at the vertebral body of a typical thoracic?
- superior epiphyseal rim to anterior longitudinal ligament
- inferior epiphyseal rim to anterior longitudinal ligament
- superior epiphyseal rim to posterior longitudinal ligament
- inferior epiphyseal rim to posterior longitudinal ligament
What are the examples of cartilaginous (amphiarthrosis) symphysis joints at the vertebral body of a typical thoracic?
- superior epiphyseal rim to intervertebral disc
- inferior epiphyseal rim to intervertebral disc
What are the examples of synovial plane (diarthrosis arthrodia) joints at the vertebral body of a typical thoracic?
- right superior costal demi-facet to inferior articular surface of the rib head
- right inferior costal demi-facet to superior articular surface of the rib head
- left superior costal demi-facet to inferior articular surface of the rib head
- left inferior costal demi-facet to superior articular surface of the rib head
How many synovial joints are formed at the vertebral body of a typical thoracic?
four
How many symphysis joints are formed with the vertebral body of a typical thoracic?
two
How many syndesmosis joints are formed at the vertebral body of a typical thoracic?
typically four are identified (as many as eight if the costocentral stellate/radiate ligaments are included)
How many joints are formed at the vertebral body of a typical thoracic?
typically ten (fourteen if the costocentral stellate/radiate 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 a typical thoracic?
four
What synovial joint surfaces are present on the vertebral body of a typical thoracic?
the right and left superior and right and left inferior costal demi-facets
What is the relationship between the vertebral body surface and the rib head surface in the costocentral joint of a typical thoracic?
- the superior costal demi-facet of the vertebral body will joint with the inferior articular surface of the head of the rib
- the inferior costal demi-facet of the vertebral body will joint with the superior articular surface of the head of the rib
Which of the demi-facets on the vertebral body of a typical thoracic is larger?
the superior costal demi-facet
What feature will provide assistance in maintaining the stability of the intervertebral foramen in the typical thoracics?
the costocentral joint or ribs
What is the rib-vertebral body combination at the intervertebral foramen for the ____ nerve? Let’s use the T6 nerve.
- the inferior costal demi-facet of T6 will joint with the superior articular surface of the head of the seventh rib
- the superior costal demi-facet of T7 will joint with the inferior articular surface of the head of the seventh rib
What ligaments support the costocentral joint?
- costocentral stellate-radiate ligament
- costocentral interarticular or intra-articular ligament
To what structures will the costocentral stellate/radiate ligament attach?
- head of the rib
- both vertebral bodies in the vertebral couple
- intervertebral disc
The costocentral stellate-radiate ligament will attach to which segments at the T3 spinal nerve intervertebral foramen?
the vertebral body of T3 and T4
What does the costocentral intra-articular or interarticular ligament connect to?
the interarticular or intra-articular crest of the head of the rib and the intervertebral disc
What is the size relationship between the articulating surface of the head of the rib and the costal demi-facet surface?
the rib surface is greater than the costal demi-facet surface
Which muscle is attached to the vertebral body of T2 or T3?
longus colli
What is the position and direction of the pedicle from the typical thoracic body?
the pedicle arises from the upper third of the vertebral body and projects posterior and slightly lateral
What is the angulation of the pedicle in the typical thoracic region?
ten to fifteen degrees posterolateral from the sagittal plane
Which x-ray view is used to see into the intervertebral foramen of a typical thoracic?
the lateral view
Which vertebral notch or incisure is said to be prominent?
the inferior vertebral notch or incisure
What is the nerve-vertebral body relationship at the typical thoracic intervertebral foramen?
in the intervertebral foramen, the number of the nerve is the same as the number of the upper thoracic in the vertebral couple
What is the rib-vertebral body relationship at the typical thoracic intervertebral foramen?
in the intervertebral foramen, the number of the rib is the same as the number of the lower thoracic in the vertebral couple
What is the appearance and position of the lamina in a typical thoracic?
the lamina is short, broad and thick and lies next to the spinous process
What is overlap of the lamina called in the typical thoracic region?
shingling
What is the outline of the vertebral foramen in the typical thoracic region?
oval to circular
In which plane will the size of the vertebral foramen of a typical thoracic be greatest?
the transverse plane, the vertebral transverse diameter
What is the direction of the transverse process in the typical thoracics?
the transverse process projects more posterior with each inferior vertebra
What is present at the tip of the transverse process of a typical thoracic?
the transverse tubercle
What is the distance between the transverse tubercles in the typical thoracic region?
from T2 each transverse diameter becomes shorter as the transverse processes angle more posterior
What is present on the transverse tubercle of a typical thoracic?
the transverse costal facet
What is the rib-transverse process relationship for the typical thoracics?
the number of the rib is the same as the number of the vertebra whose transverse process is being studied; fifth rib with T5 transverse process
What is the orientation of the transverse costal facets for T2-T6?
they face forward and outward
What is the orientation of the transverse costal facets for T7-T8?
they face forward, outward, and upward
What is the classification of the costotransverse joint?
synovial plane (diarthrosis arthrodia) joint
What are the osseous parts of the costotransverse joint?
- transverse costal facet
- articular surface of the tubercle of a rib
What ligaments support the costotransverse joint of a typical thoracic?
- superior costotransverse ligament
- inferior costotransverse ligament
- lateral costotransverse ligament
The superior costotransverse ligament of rib five will attach to which segmental bony feature?
the transverse process of T4
The inferior costotransverse ligament of rib five will attach to which segmental bony feature?
the transverse process of T5
The lateral costotransverse ligament of rib five will attach to which segmental bony feature?
the transverse process of T5
What ligaments attach to the transverse process of a typical thoracic?
- intertransverse
- capsular costotransverse
- superior costotransverse
- inferior costotransverse
- lateral costotransverse
Which joint classification is associated with the intertransverse, superior costotransverse, inferior costotransverse, and lateral costotransverse ligaments?
fibrous (amphiarthrosis) syndesmosis joint
What muscles may attach to the transverse process of a typical thoracic?
- longissimus thoracis
- longissimus cervicis
- longissimus capitis
- semispinalis thoracis
- semispinalis cervicis
- semispinalis capitis
- multifidis
- rotator longus
- rotator brevis
- intertransversarii
- levator costarum longus
- levator costarum brevis
Of the muscles attaching to the transverse process of a typical thoracic, which ones will attach only to the T5-T8 vertebral segments?
- semispinalis thoracis
- levator costarum longus
Which of the muscles attaching to the transverse process of typical thoracics are examples of the erector spinae group?
longissimus muscles
Which erector spinae muscles will not attach to the transverse process of typical thoracics?
spinalis and iliocostalis muscles
Which of the muscles attaching to the transverse process of typical thoracics are examples of the transversospinalis muscle group?
- semispinalis
- multifidis
- rotators
How can you distinguish between a T2-T4 from T5-T8 segment using the articular process?
- at T2-T4 the width between the superior articular processes is greater than the width between the inferior articular processes of that vertebra
- at T5-T8 the width between the superior articular processes is equal to or the same as the width between the inferior articular processes of that vertebra
How do the transverse diameters of the articular processes compare in the T2-T4 region?
the superior articular process transverse diameter is greater than the inferior articular process transverse diameter for a given segment
How do the transverse diameters of the articular processes compare in the T5-T8 region?
the superior articular process transverse diameter is the same as or equal to the inferior articular process transverse diameter for a given segment
What is the angulation of the articular facet of a typical thoracic?
about ten to twenty degrees from the coronal plane; sixty degrees from the horizontal plane
What is the orientation of the superior articular facet of a typical thoracic?
they face backward, upward, and lateral (BUL)
What is the orientation of the inferior articular facet of a typical thoracic?
they face forward, downward, and medial (ForMeD)
What is the curvature of the superior articular facet of a typical thoracic?
they are slightly convex
What is the curvature of the inferior articular facet of a typical thoracic?
they are slightly concave
What is the joint classification of the articular facet joint?
synovial plane (diarthrosis arthrodia) joint
How many synovial joints are present at a typical thoracic?
ten
Identify the synovial joint surfaces present on a typical thoracic.
- two superior costal demi-facets
- two inferior costal demi-facets
- two transverse costal facets
- two superior articular facets
- two inferior articular facets
How many synovial joint surfaces for ribs are present on a typical thoracic?
six
Identify the synovial joint surfaces for ribs that are present on a typical thoracic.
- two superior costal demi-facets
- two inferior costal demi-facets
- two transverse costal facets
What is the relationship of the inferior articular process and the lamina?
they blend together
What is the name given to the region between the superior and inferior articular processes in the typical thoracics?
the pars interarticularis
What part of a vertebra arises laterally from the pars interarticularis?
the transverse process
What part of a vertebra arises medially from the pars interarticularis?
the lamina
What is the orientation of the spinous process of a typical thoracic?
they slant backward and downward
What is the name given to the overlap of spinous processes in the thoracic region?
imbrication
Imbrication will be more pronounced for what region of the thoracics?
T5-T8
Which thoracic has the longest spinous process?
T8
How will the angulation of the spinous process be measured?
from the horizontal plane to the undersurface of the spinous process
What is the angulation of the spinous process in the typical thoracic region?
- the undersurface of T2-T4 spinous processes will angle up to 40 degrees from the horizontal plane
- the undersurface of T5-T8 spinous processes will angle up to 60 degrees from the horizontal plane
What is the name of the osseous feature at the tip of the spinous process?
the spinous tubercle
What ligaments attach to the spinous process of a typical thoracic?
- interspinous
- supraspinous
What joint classification is associated with typical thoracic spinous process ligaments?
fibrous (amphiarthrosis) syndesmosis joint
Which muscles may attach to the spinous process of a typical thoracic?
- trapezius
- latissimus dorsi
- rhomboid major
- serratus posterior superior
- splenius cervicis
- splenius capitis
- spinalis thoracis
- spinalis cervicis
- spinalis capitis
- semispinalis thoracis
- multifidis
- rotator longus
- rotator brevis
- interspinalis
Of the muscles attaching to the spinous process of typical thoracics, which will attach only to the T5-T8 vertebral segments?
latissimus dorsi
Of the muscles attaching to the spinous process of typical thoracics, which ones are examples of the erector spinae group?
the spinalis muscles
Which erector spinae muslces will not attach to the spinous process of typical thoracics?
longissimus and iliocostalis muslces
Of the muscles attaching to the spinous process of typical thoracics, which ones are examples of the transversospinalis muscle group?
- semispinalis
- multifidis
- rotators
What muscles are associated with the five muscle layers of the true back?
- layer one consists of the trapezius and latissimus dorsi
- layer two consists of the rhomboids and levator scapulae
- layer three consists of the serratus posterior
- layer four consists of the erector spinae
- layer five consists of the transversospinalis
Which of the muscles of the five layers of the true back are present at the spinous process of a typical thoracic?
- trapezius
- latissimus dorsi
- rhomboid major
- serratus posterior superior
- spinalis thoracis
- spinalis cervicis
- spinalis capitis
- semispinalis thoracis
- multifidis
- rotator longus
- rotator brevis
Which muscles attaching to the spinous process of a typical thoracic are not included in any muscle layer of the true back?
- splenius cervicis
- splenius capitis
- interspinalis
What joint classifications are present at every typical thoracic vertebra?
- fibrous (amphiarthrosis) syndesmosis
- cartilaginous (amphiarthrosis) symphysis
- synovial plane (diarthrosis arthrodia)
The fibrous (amphiarthrosis) syndesmosis joint will occur at what parts of a typical thoracic vertebra?
- vertebral body
- lamina
- transverse process
- spinous process
At what part of a typical thoracic vertebra will the cartilaginous (amphiarthrosis) symphysis joint be observed?
vertebral body
At what parts of a typical thoracic vertebra will the synovial plane (diarthrosis arthrodia) joint be observed?
- vertebral body
- transverse process
- articular process