Ribs & Sternum- Anatomy & Pathology

bony thorax is formed by…

the sternum, 12 rib pairs, & 12 thoracic vertebrae

purpose of bony thorax

supports walls of pleural cavity and diaphragm that are used during respiration

• allows volume of cavity to be varied during respiration

• protects heart & lungs

the bony thorax is __ shaped

conical

what type of bones are ribs?

flat

ribs characteristics

• long, narrow, & curved w/ an anteriorly attached piece of cartilage called costal cartilage

  • situated in an oblique plane slanting anterior & inferior

head of rib, articulates w/

body of vertebra

what is the flattened area between the neck & tubercle

neck of rib

tubercle of rib has a facet that articulates with…

transverse process of vertebra

what is the end of the rib which attaches to the thoracic vertebra?

vertebral end of rib

what is posteriorly, before connection to vertebra?

angle of rib

what is the lateral aspect curved section located near the axillary

axillary portion of rib

end of rib that attaches anteriorly

sternal end

what is located on the inferior/ internal border & contains costal arteries, veins, and nerves.

costal groove

Trauma to the ribs can damage this area and cause pain and hemorrhaging

costal groove

costovertebral joint

• head connects to vertebral body

• synovial gliding

costotransverse joint

• tubercle connects to transverse process

• synovial gliding

ribs that are 1-7 & attach DIRECTLY to the STERNUM

true ribs

ribs that are 8-12 & do NOT attach directtly to the sternum

false ribs

ribs that are 11 & 12 & attach ONLY TO THE VERTEBRAE

floating ribs

costochondral joint

• anterior connection of sternal end of rib with the costal cartilage

  • cartilaginous synchondroses joints & allow NO MOVEMENT

joints that are located between the costal cartilages of 6-7, 7-8, 8-9, & 9-10

interchondral joints (synovial gliding)

what is the space between each rib

intercostal space

the diaphragm moves approximately __” between deep inspiration & deep expiration

1 ½”

what ribs are best examined on ABOVE the diaphragm, on inspiration?

1-9

what ribs are best examined BELOW the diaphragm, on expiration?

8-12

the rib cage is widest at what ribs?

8th & 9th

cervical rib

• an anomaly that some people have

what bone is the sternum?

flat

3 parts of the sternnum

1. manubrium

2. body

3. xiphoid

what supports the clavicles & provides attachments to costal cartilages of first 7 ribs?

sternum

clavicular notches

• on the superior lateral sides where the sternal end of the clavicles articulate

(ex: SC joints)

costal notch

• for the cartilage of the 1st rib attachment

jugular notch corresponds to what vertebrae?

T2/T3

sternal angle corresponds to level of

T4/T5

body of sternum overview

• costal notches

  • attachments of ribs 2-7

  • attachments of costal cartilage to sternum (sternocostal joints- synovial)

what is Cartilaginous early in life then partially or completely ossifies later in life.

xiphoid process

palpable & corresponds to the superior portion of liver & inferior aspect of the heart

xiphoid process

xiphisternal joint

• joint space between sternal & xiphoid

  • cartilaginous synchondrosis joint (allows little to no movement)

xiphoid process lies at

T10

RAO sternum- large barrel chest patient

15 degree oblique

RAO sternum- thin chested patient

20 degree oblique

presence of air in subcutaneous tissue

subcutaneous emphysema

radiographic appearance of subcutaneous emphysema

• streaks or lucency within the soft tissue of the chest that outlines the muscle bundles- no tech change unless lot of air- then decrease

what pathology is this?

subcutaneous emphysema

what pathology is this?

rib fracture

what pathology is when 2 or more continuous rib fractures with 2 or more breaks per rib?

flail chest

flail chest radiographic appearance

fracture of adjacent ribs in 2 or more places

what pathology is this?

flail chest

what is an uncommon birth defect in which a child’s breastbone protrudes outward abnormally?

pectus carinatum- pigeon chest

radiographic appearance of pectus carinatum- pigeon chest

anterior protrusion of the lower sternum & xiphoid process

what pathology is this?

pectus carinatum- pigeon chest

what is the condition in which the person’s breastbone is sunken into the chest?

pectus excavatum- funnel chest

radiographic appearance of pectus exacatum- funnel chest

depressed sternum

what pathology is this?

pectus exacatum- funnel chest

large barrel chest patient needs __ degrees for RAO sternum

15

thin chested patient is __ degrees for RAO sternum

20

What is 1 on this sternum?

manubrium

What is 2 on this sternum?

sternal angle

What is 3 on this sternum?

body

what is 4 on this sternum?

xiphoid process

what is A on this sternum RAO?

jugular notch

what is B on this sternum RAO?

SC joint

what is C on this sternum RAO?

manubrium

what is D on this sternum RAO?

manubriosternal joint (forms sternal angle)

what is E on this sternum RAO?

costal notch

what is F on this sternum RAO?

body

what is G on this sternum RAO?

xiphoid process

what is 1?

jugular notch

what is 2?

manubrium

what is 3?

sternal angle

what is 4?

body

what is 5?

clavicular notch

what is 6?

facets of costal cartilages 1-7

what is 7?

xiphoid

what is 1?

tubercle

what is 2?

angle

what is 3?

articular facet

what is 4?

costal groove

what is 5?

axillary portion

what is 6?

shaft

diaphragm moves approx. __ between deep inspiration & deep expiration

1.5 inches

what type of joints are sc joints?

synovial gliding joints