1750 Bony Thorax Anatomy PP

What Makes up the Bony Thorax

Sternum, 12 Pairs of ribs, 12 thoracic vertebrae

What shape is the bony thorax

Conical, narrower above than below, more wide than deep, and longer posteriorly than anteriorly

What direction is the sternum?

Anterior and inferior

What type of bone is the sternum

Flat bone, 6 inches long

What are the three parts of the sternum

Manubrium, body, and xiphoid process

What portion of the sternum supports the clavicles

Superior manubrial angles

What do the lateral borders of the sternum do

Provide attachment to the costal cartilages of the 1st seven pairs of ribs

What shape is the manubrium

Quadralateral in shape and the widest part of the sternum

What are the other names for the jugular notch

Manubrial notch and suprasternal notch

Where does the jugular notch lie

Anterior to the interspace between the second and third thoracic vertabrae

Where does the manubrium lie anatomically

Slants laterally and posteriorly on each side of the jugular notch and bears an articular surface for the reception of the sternal extremity of the clavicle called the clavicular notch. Immediately below the articular notches for the clavicles are shallow depressions for the attachment for the cartilages of the 1st pair of ribs.

What is the longest part of the sternum?

Sternal body (4 inches)

Where does the sternal body join with the manubrium

Sternal angle

What type of angle is the sternal angle

Obtuse angle

Where does the sternal angle lie

The level of the junction of the second costal cartilage. Anterior to the interspace between 4th and 5th thoracic vertebrae

Which costal cartilages are attached to the lateral borders of the body

3-7th costal cartilages

Where does the xiphoid process lie

Distal, smallest portion, lies over T10, often deviates from midline

How many pairs of ribs are there

12 pairs

Where do the ribs lie anatomically

In an oblique plane slanting anteriorly and inferiorly

Where do the anterior ends lie

3-5 inches below the level of their vertebral ends

How does the obliquity change?

It gradually increases from the 1st - 9th and then decreases to the 12th rib

What are the spaces between the ribs called

Intercostal spaces

Which rib is the shortest and broadest

1st rib

Which is the narrowest rib

12th rib (Breadth gradually decreases)

What are the parts of the ribs

Head, flattened neck, tubercle, and body

How does the length of the ribs change

Gradually increases from 1st to 7th ribs and then decreases to 12th rib

How does the rib project posteriorly

At an oblique angle to the point of articulation with the anterior surface of the transverse process and the tubercle of the rib (Costotransverse joint)

What is the head of the rib closely bound to?

The demifacets of two adjacent vertebral bodies for the costovertebral joint

What is located on the inferior and internal border of each rib

The costal groove

What does the costal groove contain

Costal arteries, veins and nerves

What does trauma to the rib do

Damages the costal groove and can cause pain and hemorrhage

Which ribs are the true ribs

1st seven pairs

Why are the true ribs named that

Because they attach directly to the sternum

Which ribs are called false ribs

8-12th ribs

Where do the false ribs attach

Superadjacent cartilage 

Which ribs are called floating ribs

11th and 12th ribs

Why are the floating ribs called that

Their cartilage ends in musculature

What are Cervical ribs

Articulate with C7, but rarely attach to sternum. May be free, articulate, or fuse with 1st rib. Congenital, 1 in 200

What are lumbar ribs

Less common than cervical ribs, can be confused as a fractured transverse process of L1

What is the classification of the Sternoclavicular joints

Synovial, Gliding, Freely Moveable 1

What is the classification of the Costovertebral: 1st -12th ribs joints

Synovial, Gliding Freely Moveable 2

What is the classification of the Costotransverse: 1st - 10th Ribs joints

Synovial, Gliding, Freely Moveable 3

What is the classification of the Costochondrial 1st - 10th ribs joints

Cartilaginous, synchondroses, immovable 1

What is the classification of the Sternocostal 1st rib joint

Cartilaginous, synchondroses, immovable 2

What is the classification of the Sternocostal 2nd-7th rib joints

Synovial, gliding, freely moveable 4

What is the classification of the interchondral 6th-9th rib joints

Syonvial, gliding, freely moveable 5

What is the classification of the interchondral 9th-10th rib joints

Fibrous, syndesmoses, slightly moveable

What is the classification of the manubriosternal joint

Cartilaginous, symphysis, slightly moveable

What is the classification of the Xiphisternal joint

Cartilaginous, synchondroses, immovable 3

How does the oblique orientation of the ribs change with deep inspiration

Decreases (Anterior ends are carried anteriorly, superiorly, and laterally while necks are rotated inferiorly)

How does the oblique orientation of the ribs change with deep expiration

Increases (Anterior ends are carried inferiorly, posteriorly, and medially while necks are rotated superiorly)

How do you examine ribs above the diaphragm

Through air filled lungs

How do you examine ribs below the diaphragm

Through Upper abdomen

Where does the diaphragm lie with hypersthenic patients

Higher

Where does the diaphragm lie with hyposthenic patients

Lower

Where does the diaphragm lie with sthenic patients

Right side of diaphragm arches posteriorly from level of about 6th or 7th costal cartilage to level of 9th or 10th thoracic vertebra when body is upright. Left side lies at a slightly lower level

Why do we examine ribs above the diaphragm upright

Because the diaphragm reaches its lowest level when body is upright

Why do we examine ribs below diaphragm supine

Because the diaphragm reaches its highest level when body is supine

What is the measure of respiratory movement between inspiration and expiration

1 ½ inches (Movement less in hypersthenic patiens and more in hyposthenic)

Pectus Carinatum

Pigeon Chest: Characterized by anterior protrusion of lower sternum

Pectus Excavatum

Funnel Chest: Characterized by depressed sternum