Thoracic (rib) Cage Flashcards
What makes up the sternum?
-manubrium (top portion)
-sternum (body)
-xiphoid (bottom portion)
What is a “true” rib?
Rib that attaches directly to the sternum (costal cartilage of rib anchors onto the sternum)
Which ribs are considered “true” ribs?
1-7
What is a “false” rib?
Rib that attaches indirectly to the sternum (costal cartilage of the rib anchors onto the costal cartilage of the rib above it)
Which ribs are considered “false” ribs?
8-10
What is a “floating” rib?
Rib that does not attach to the sternum at all
Which ribs are considered “floating” ribs?
11-12
What is a typical rib?
Ribs that all share similar landmarks
Which ribs are considered typical ribs?
3-9
What is an atypical rib?
Ribs that do not share similar landmarks
Which ribs are considered atypical ribs?
1-2, 10-12
What are the landmarks of typical ribs (3-19)?
-head
-neck
-tubercle
-shaft/body
-costal angle
How would you describe the head of a typical rib?
Portion of the rib that has facets which articulate with two different vertebrae to allow the rib to have some movement
How would you describe the neck of a typical rib?
Narrow smooth portion of the rib distal to the head
How would you describe the tubercle of a typical rib?
lateral lumps/bumps that create a surface which articulates with the transverse processes of thoracic vertebrae
How would you describe the shaft/body of a typical rib?
Thin/flat portion of the rib which wraps around
How would you describe the costal angle of a typical rib?
Transition point where the proximal arrangement of the rib (head/neck/tubercle) turns into the shaft/body of the rib
What is a common site for the rib to fail/fracture?
The costal angle- if rib is being compressed on both sides will likely snap at this part (but can happen anywhere)
Which vertebrae are thoracic vertebrae?
1-12, bony part of the back portion of the ribcage
What is the superior aperture of the rib cage?
Top opening of the rib cage
-gateway for structures which need to pass to the head/upper extremities
What does the superior aperture of the rib cage contain?
-esophagus
-trachea
-nerves/vessels that supply head, neck, and upper extremities
What is the inferior aperture of the rib cage?
The bottom opening of the rib cage which is lined/covered by the diaphragm
-diaphragm has openings which allow structures to pass from the inferior aperture to the abdomen
Which structures does the inferior aperture of the rib cage allow to pass below the abdominal cavity?
-esophagus
-IVC (inferior vena cava)
-aorta
What is a costochondral joint?
Point where the rib articulates with the costal cartilage
What is a sternocostal joint?
Point where the costal cartilage articulates with the sternum
What is a manubriosternal joint?
AKA the sternal angle, junction between manubrium and sternal body
What is a xiphisternal joint?
Junction between xiphoid (bottom of sternum) and sternal body
What is a sternoclavicular joint?
Point where the clavicle articulates with the sternum
How does the thoracic cage move during inspiration?
“Bucket handle” motion will pull the ribs up and out
Which increases/expands: anterior-posterior diameter & lateral diameter
**expansion should be equal on both sides in a healthy individual
What movement highlights would you look for on a physical exam of the rib cage?
rate, symmetry, and quality of movement during inspiration and expiration
What is the “accessory pattern” of movement in the rib cage? What conditions cause this pattern?
Accessory pattern: shrug of shoulders when breathing, work of breathing is more difficult for muscles so they recruit the accessory muscles to help out
Overuse of the accessory muscles will cause hypertrophy in this area
Common in: COPD and other pulmonary diseases
What is the “asymmetrical pattern” of movement in the rib cage? What conditions cause this pattern?
Asymmetrical pattern: rib cage will not expand symmetrically when breathing
Common in: trauma/pathology to one lung (pneumothorax, etc.), scoliosis or displacement of spine
What muscles are used during inspiration at rest?
-diaphragm
-external intercostals
What muscles are used during inspiration during exertion/exercise or in pathology?
-diaphragm
-external intercostals
PLUS
-accessory muscles: SCM and scalenes
-pecs may also assist
(these will also be recruited in inspiration at rest in diseases like COPD)
What muscles are used during expiration at rest?
Only really elastic recoil of lungs
What muscles are used during expiration during exertion/exercise or in pathology?
-internal intercostals
-abdominal muscles (rectus abdominis, interior/exterior oblique)
