Thorax 2 Flashcards
What does the sternum form
The middle of the anterior part of the thoracic cage
What shape is the sternum
- flat
- elongated bone
What are the three parts of the sternum
- manubrium
- body
- xiphoid process
What is the sternal angle between
The manubrium and the body of the sternum
What is known as the trapezoidal bone
Manubrium
What part of the sternum is the thickest and the widest part
Manubrium
What is known as the easily palates venter of the superior border of the manubrium
The jugular notch
What does the claviclar notch connect
The clavicle and the sternum
What is attached to the lateral border if the manubrium
The costal cartilage of the first rib
Deceive what synchondrosis is
This is where the costal cartilage of the 1st rib meats the lateral border of the manubrium
Is there a synovial joint between the 1st rib and sternum?
No, it is a synchondrosis, that is why there is NO movement between the 1st rib and sternum
The manubristernal is Also called?
The sternal angle of Louis
What is the sternal angle a landmark for
Descending aorta
At what level of the vertebra is the body of the sternum located
From T5-T9
Why does the width of the body of the sternum vary
It varies because of the costal notches on the lateral parts of the sternum
Is the sternum separated or fused when you are born
It’s starts off separated and fuses with adulthood
The joints between the sternebra begin to fuse when
Between puberty and age 25
Tell me when the different sternebrae fuse ( specifically what ages)
*remember these joints begin to fuse from the inferior end
(Closer to jugular notch) 1&2-age 60 2&3-age 25 3&4= age 19 4&5= age 12 5&6= age 40
What ossifies with age in the sternum
The Xiphoid process
What is the smallest and variable part of the sternum
The xiphoid process
At what vertebral level does the xhiphoid process lie
T10
What is cartilaginous in young people but may be ossified in adults
The xiphoid process
What may happen with old people in regards to the xiphoid process and the sternal body
It may fuse with the sternal body and become hardened, people often think it is a tumor
The xiphoid process is a landmark for what
The median plane
The infrasternal angle (sub costal angle) is located under what
The xiphoid process, in the inferior thoracic aperture
The xiphoid process is a midline marker for what structures
- The liver
- the central tendon of the diaphragm
- the inferior border if the heart
At what age do people normally become aware of the ossification of their xiphoid process
At around age 40
Are sternal fractures common?
No
What can cause a sternal fracture
Crush injuries where a person’s chest can be slammed between the steering wheel and the seat
What has dramatically reduced the number if sternal fractures
Air bags:)
When a sternum is fractured it usually breaks how?
Comminuted fracture- usually breaks into many different peices
Why is displacements of fractures that happen in the sternum uncommon??
It is uncommon because the sternum is invested in the deep fascia and the sternal attachment if the pectoral is major muscles
Where is the most common site for a sternal fracture
The sternal angle!!
Why is there such a concern with sternal injuries
Because it could cause a myocardial contusion, cardiac rupture, and tamponade
Basically it can hurt the heart!!
For cardiac tamponade can you save the patient?
Yes if you work quickly
What is the percentage if people who die due to sternal fractures
25-45%
All patients with sternal contusions should be evaluated for what??
Underlying visceral(organ) injury
Compression of the heart by an accumulation of fluid in the pericardial sac is known as what
Tamponade
When a laceration or tearing of the walls of the ventricles or atria has been made or the interventricular septum or the papillary muscles or the chordate trendiness, had been made this is known as what
Cardiac rupture
What is referred to as a contusion it bruise of the cardiac muscle?
Myocardial contusion
What usually causes a myocardial contusion?
What portion of the heart is thought to be the most easy for a myocardial contusion to occur
Usually due to blunt trauma of the anterior part of the thoracic wall
The right part of the heart is most likely to have this occur due to the position
What is another name for a myocardial infraction
A heart attack
What usually is caused by a blood clot of the heart and happens when the blood stops flowing to a part of the heart muscle
Myocardial infarction (HEART ATTACK)
What is performed to gain access to the thoracic cavity during surgical procedures in the mediastinum
Median sterenotomy
When performing a median sterenotomy where is the sternum split
In the median plane of the sternum, and then it is retracted (pulled towards the right and left)
What enables spreading the sternum into two halves
The flexibility of the ribs and their costal cartilages!
What gives good exposure for removal of rumors and the superior lobes of the lungs
Sternal splitting(median sternotomy)
What do surgeons use to join the sternum together after a sternotomy
Wire sutures
What can the sternal body be used for, other than a sternotomy
A bone marrow biopsy, because of its width and subcutaneous position
What is aplastic anemia
This is when blood marrow begins to be replaced by fibrous tissue
THIS CAN CAUSE DEATH DUE TO LACK OF BLOOD CELLS
What are the names for the superior and inferior openings of the thoracic wall
- Superior thoracic aperture
2. Inferior thoracic aperture
Which thoracic aperture allows communicate with the neck and upper limbs
The superior thoracic aperture
Which thoracic aperture provides a ring like origin if the diaphragm
Inferior thoracic opening
What completely occluded the opening if the inferior thoracic aperture
The diaphragm
What primarily controls the volume and internal pressure of the thoracic cavity
Diaphragm
What is the posterior portion of the superior thoracic aperture
- anterior
- lateral
- T1
- manubrium
- 1st rib
What structures pass through the superior thoracic aperture
- trachea
- esophagus
- nerves
- vessels (supply and drain the neck and upper limbs)
Why does the superior aperture slant forward
Because of the obliquity of the 1st pair ribs
Which aperture is more spacious
The inferior thoracic aperture
The diaphragm separates what
The thorax and the abdominal cavity
The diaphragm has three opening for what
Inferior Vena cava hiatus
Aortic hiatus
Esophagus hiatus
The domes of the diaphragm raise to where
The 4th intercostal space
What muscles occupy the intercostal spaces
Intercostal muscles
The superficial layer of the intercostal muscles are what? The inner layer is what?
- external intercostals
- internal intercostals
Putting your hands in your front pockets of your jeans represents the direction of what intercostal muscles
External
How many pairs are there of external intercostal muscles
11
When are the external intercostal muscles most active
During FORCED inspiration
When are the internal intercostal muscles most active
During FORCED explorations
Do you necessarily need the intercostal muscles for regular breathing
No, not during forced
How many pairs are there of internal intercostals
11
Which internal intercostal muscles are the weakest
The internal intercostal muscles
When are the internal intercostal muscles most active
During expiration
What separates the innermost intercostal kicked from the internal intercostal muscles
Intercostal nerves and vessels
Where are the subcostal mucked located?
In the lower thoracic wall
The subcostal muscles act with what other muscle
The internal intercostals
Where are the transverse thoracic (transverse thoracis)
They attach to the inferior part of the body of the sternum, and the posterior portion of the xiphoid process
How many slips do the transverse thoracis consist of
4 of 5 slips
What costal cartilages do the transverse thoracis muscles attach too
2nd-6th costal cartilages
Do the transverse thoracic muscles affect expiration?
Only a little bit they pull down on the costal cartilages that they attach too
What may provide propioceptive information( let you know how far you are bending so you don’t fall over)
Transverse thoracis muscles
What is the primary muscle of inspiration
Diaphragm
Is expiration passive or active motion
Passive motion
What are examples of forced expiration
Coughing
Sneezing
Blowing your nose
Shouting
What does dyspnea mean
Difficulty breathing
What muscles do people use to breathe when they have heart problems or asthma
I.e they have to bend over to expand their thoracic cavity
Or they lean over a chair
Accessory respiratory muscles
Mammary glands are accessory to reproduction of women but what to men
Functionless
Glandular system of breast do not develop in who
Men
What are the most prominent superficial structures in the anterior thoracic wall, especially in women
The breasts
What determines the size if the non lactating breasts
Amount if fat surrounding the glandular tissue
The nipple is surrounded by what?
The areola it is a pigmented portion if skin
What is the most prominent sweat gland in both men and women
The breasts
He breast lines between what ribs
2nd-6th
2/3 of the breast are formed by what
The pectoral fascia that overlies the pectoralis major
1/3 of the breast is where
Formed by the fascia that covers the serratus anterior
Where is the retromammary space (bursa)
Between the breast and the pectoral fascia
A small part if the mammary gland can extend to where
To the axillary fossa(armpit)
Why is it that when men have breast cancer it is spread to the body faster
Because they have no retromammary space, so there is no barrier between boob and body
Why is pain in the breasts during menstrual cycle normal
Because water accumulates in the tissue
How is the beast attached to the dermis of the overlying skin
By skin ligaments called Reticula Cutis
Where are more Reticula cutis located
More in the upper portion of the boob
This helps support the mammary gland lobules
What are the ligaments that attach to the dermis and have more in the upper portion of the boob compared to the bottom
The suspensory ligaments of Cooper
At what she in puberty do the boobs normally enlarge
Sitting 8-15
What three things determine breast size
Genetics
Ethnicity
Diet
How many lobules of glandular tissue are there in the boob
15-20
What portion of the breasts produce milk
The lobules
Each lobule is drained by what
A lactiferous duct
Where does the lactiferous duct open
Independently on the nipple
Deep to the areolar the lactiferous ducts beach have a dilated portion called what
Lactiferous sinus
The small milk droplets that accumulates and that can maintain in the nursing mother happens where
Lactiferous sinus
What contains many sebaceous glands in the breast
Areola
What enlarges during pregnancy and secretes and oily substance to provide chapping if the nipple
The areolar
What part of the breast has no hair, fat or sweat gland
The nipple
What portion of the breast is composed if circularly arranged smooth muscle fibers that compress the lactiferous duct during lactation
The nipple
What happens to nipples in response to stimulation?
They erect
JUST FOR YOUR KNOWLEDGE GUYS:))
The Breasts don’t produce milk during pregnancy because a high level of progesterone is present, but once the baby is born the progesterone drops there for stimulating secretion from the breasts because prolactin increases and stops the progesterone production
You are welcome:)
What is a modified sweat gland
Mammary gland
Most of the volume of the breast is produced by what
The subcutaneous fat
What have some people been known to use as a natural contraceptive
Breast feeding
