Level 2 - Thoracic Cage Flashcards
How is the thoracic cage bound posteriorly?
12 thoracic vertebrae
How is the thoracic cage bound anteriorly?
The sternum
How is the thoracic cage bound laterally?
12 pairs of ribs
Formed posteriorly by the first thoracic vertebrae, laterally by the ribs, and anteriorly by the manubrium sterni
Thoracic inlet
T/F
The pleural apicies project just above the thoracic inlet
True
What passes through the thoracic inlet?
Main vessels, nerves, trachea, esophagus
Formed posteriorly by the 12th thoracic vertebrae, anteriorly by costal cartilage and laterally by the ribs
Thoracic outlet
What is the thoracic outlet closed by?
Diaphragm
Dagger shaped bone in the middle of the anterior chest
Sternum
What are the 3 parts of the sternum?
Manubrium
Body
Xiphoid
Upper handle part of the sternum
Manubrium
Middle blade part of the sternum
Body
Blunt cartilaginous lower tip that ossifies during adult life
Xiphoid tip
Articulated with the clavicle and first rib costocartilage
Manubrium
What type of bone is the sternum?
Long flat bone
What direction does the sternum point?
Directed down and slightly forward
What types of bone is the sternum comprised of?
Highly vascular cancellous bone, containing red marrow, covered in compact bone
What is the level of the jugular notch?
T2/3
What is the level of the Manubrium sterni?
T3/4
What is in the Center of the superior border of the Manubrium sterni?
Suprasternal (jugular) notch
What are on either side of the suprasternal notch for the articulation with the medial end of the clavicle?
Clavicular notches
Articulation between the Manubrium and the superior end of the body of the sternum
Sternal angle
Level T4/5
How many transverse bony ridges are on the anterior surface of the body of the sternum?
3
What is the joint called where the body articulates with the xiphoid?
Xiphisternal joint
What vertebral level is the xiphoid?
T9/10
How many pairs of ribs are there?
12 pairs
Long, slender highly vascular spongy bones covered in a thin layer of compact bone and contain a large portion of red marrow
Ribs
Where do ribs articulate?
Posteriorly with thoracic vertebrae
How do ribs curve?
Outward, then forward and downward
Which ribs attach to the sternum?
Only ribs 1-10
T/F
Ribs end anteriorly with costal cartilage
True
What ribs are classified as true ribs, articulating directly with the sternum
Ribs 1-7
What ribs are classified as false ribs, not directly articulating with the sternum?
Ribs 8-12
What ribs are indirectly attached to the sternum? (Costal cartilage articulates with the cartilage above)
8,9,10
Which ribs are known as floating ribs because their costal cartilage does not attach directly or indirectly
11-12
Which ribs are typical?
3-9
-long curved shaft with anterior and posterior ends
-superior border: blunt
-inferior border:sharp
Where is the costal groove that shelters the neurovascular bundle (arteries, veins, nerves)
Internal surface
T/F
The anterior end of the rib is slightly concave to receive the costal cartilage
True
What joint is formed between the rib and costal cartilage
Costochondral joint
What is a common site for fracture when ribs are under physical stress?
Rib angle: maximum curvature
Covered with articular cartilage, has two facets that articulate with the demifacets on the adjacent vertebrae to form costovertebral joints
Head
(Posterior end)
Short flattened portion of the rib, which is a site of attachment for ligaments
Neck
(Posterior end)
Has a medial articulating surface on it that attaches to the facet of the transverse process of the corresponding vertebrae to form the costotransverse joint
Tubercle
(Posterior end)
T/F
Only the T spine articulates with ribs
True
T/F
The inferior articular surface on the rib articulates on the superior part of the corresponding vertebrae
True
Rub articulation with the thoracic body
Costovertebral joint
Which ribs only articulate with their corresponding vertebrae T spine?
1,10,11,12
Which ribs also articulate with the T spine body above?
Ribs 2-9
Rib articulation with thoracic transverse process
Costotransverse joint
Ribs 1-10
Which ribs do not articulate with the transverse process because they do not have tubercles?
Ribs 11,12
Which ribs are considered atypical?
Ribs 1,2,10,11,12
Short, broad and flat rib
Inner border is concave
Outer border is convex
First rib
Which rib has a prominent tubercle at the angle called the scalene?
First rib
It’s costal cartilage passes under the clavicle to articulate with the Manubrium sterni laterally
First rib
Almost twice as long as the first rib, lies flat
Second rib
Which ribs do not have a tubercle or a neck, and their anterior ends are pointed and tipped with costal cartilage
10,11,12
Which ribs end in the muscles of the abdominal wall?
10,11,12
Head of the rib joining the thoracic vertebral body
Costovertebral
Ribs 2-9
Tubercles of the rib joining the thoracic transverse process
Costotransverse
Which ribs do not have costotransverse joints?
11,12
What type of joint is the costovertebral joint?
Synovial, gliding (plane)
What type of joint is the costotransverse joint?
Synovial, gliding (plane)
What type of joint is the Sternoclavicular joint?
Synovial, saddle joint
(Elevation, depression, protraction, retraction, rotation)
What type of joint is the sternocostal joint of the first rib?
Synchondrosis
(Only moves slightly)
What type of joint is the sternocostal joints of the 2-7 rib?
Synovial, gliding
Symphysis between the Manubrium sterni and body of the sternum
Manubriosternal joint
Symphysis between the xiphoid and the body of the sternum
Xiphisternal joint
Adjacent borders of the lower costal cartilages articulate with themselves.
Synovial plane joints
Interchondral joints
Large dome shaped musculofibroys sheet separating the thoracic and abdominal cavities
Diaphragm
What are the three muscle fibre groups in the diaphragm and where do they insert?
Sternal, costal, lumbar
Insert into the central tendon of the diaphragm
What level is the diaphragm when relaxed?
T8
T/F
When the diaphragm contracts the muscles shorten and the central tendon is pulled down increasing the length of the thoracic cavity
True
External intercostal muscles also contract to increase thorax size
What is the superior surface of the diaphragm covered in?
Pleura (separates the diaphragm from lungs)
Pericardium (separates diaphragm from heart)
Level of T8, highest and most anterior
Transmits vena cava and right phrenic nerve
Vena caval aperture
Level of T10
Transmits the esophagus
Oesophageal aperture
Level of T12
Lowest and most posterior
Lies behind the diaphragm
Transmits aorta, thoracic duct and azygos vein
Aortic aperture
