Thorax Osteology Flashcards
What is the typical number of thoracic vertebrae?
12
What is the primary characteristic of thoracic vertebrae?
Presence of costal facets for articulation with ribs
Which part of the thoracic vertebrae articulates with the head of the rib?
Costal facets on the vertebral body
Where are the costal facets located on thoracic vertebrae for tubercle of the rib?
On the transverse processes
What is the shape of the thoracic vertebral body?
Heart-shaped
How do the spinous processes of thoracic vertebrae typically project?
Long and project inferiorly, overlapping the vertebra below
Which thoracic vertebrae have atypical features?
T1, T9-T12
Why is T1 considered atypical?
It has a complete costal facet for the 1st rib and a demifacet for the 2nd rib
What is unique about T9?
It may lack a demifacet for the 10th rib
What is unique about T10-T12?
They have a single complete costal facet on their bodies (no demifacets)
What is the orientation of the articular processes in thoracic vertebrae?
Coronal plane, allowing for rotation but limiting flexion/extension
What is the function of the superior and inferior costal facets?
Articulate with the heads of ribs
What is the clinical significance of the T4 vertebral level?
Level of the sternal angle (angle of Louis), important for anatomical landmarks
What is the vertebral level of the inferior angle of the scapula?
T7
What is the significance of the T12 vertebra?
Transitional vertebra with features of both thoracic and lumbar vertebrae
What is the name of the joint between the rib and the thoracic vertebral body?
Costovertebral joint
What is the name of the joint between the rib and the transverse process of the thoracic vertebra?
Costotransverse joint
What is the role of the intervertebral discs in the thoracic region?
Provide cushioning and allow for limited movement
What is the kyphotic curvature of the thoracic spine?
A posterior convex curvature, typical of the thoracic region
What is the significance of the T7-T9 vertebrae in relation to the diaphragm?
They are at the level where the diaphragm attaches to the lower ribs
What is another name for the Angle of Louis?
Sternal Angle
The sternal angle is formed by the articulation of which two structures?
Manubrium and body of the sternum
At which vertebral level is the sternal angle located?
T4-T5
Which rib articulates at the sternal angle?
2nd rib
What important cardiovascular structure begins and ends at the sternal angle?
Arch of the aorta
The bifurcation of which airway structure occurs at the sternal angle?
Trachea (into right and left bronchi)
Which venous structure begins at the sternal angle?
Azygos vein drains into the superior vena cava
Which heart valve lies closest to the sternal angle?
Pulmonary valve
Which structure marks the transition from ascending aorta to the aortic arch?
Sternal angle (T4-T5 level)
Which plane is defined by the sternal angle and divides the mediastinum?
Transverse thoracic plane
What are the three parts of the sternum?
Manubrium, body, xiphoid process
Which structure articulates with the clavicle at the sternum?
Manubrium (at the sternoclavicular joint)
Which ribs articulate with the manubrium?
1st rib (directly), 2nd rib (at the sternal angle)
Which ribs articulate directly with the body of the sternum?
Ribs 3-6
What landmark is present at the lower end of the sternum?
Xiphoid process
At which vertebral level is the xiphoid process located?
T9-T10
What is the clinical significance of the xiphoid process?
Used as a landmark for CPR hand placement
Which condition results from incomplete fusion of the sternum during development?
Sternal cleft or pectus excavatum
Which bone marrow procedure involves the sternum?
Sternal bone marrow aspiration (sternal puncture)
Which important anatomical plane runs through the sternum?
Median sagittal plane
