ANATOMY Flashcards
What are the 6 functions of the thorax?
- protection
- rigidity
- elasticity
- locomotion
- haematopoiesis
- respiration
Which of the transverse and sagittal diameter of the thorax is the largest?
transverse
What makes the rib cage?
sternum + 12 pairs of ribs and their costal cartilages + 12 thoracic vertebrae and intervertebral discs
What makes the thoracic wall?
thoracic cage
+ skin
+ subcutaneous tissue
+ thoracic muscles (pectoralis major, pectoralis minor, serratus anterior, serratus posterior inferior, serratus posterior superior) and fascia
+ intercostal muscles (external, internal and innermost intercostal muscles)
+ mammary gland and breast tissue
How do thoracic vertebrae limit movement?
superior and inferior facets are vertical and face slightly medially –> allow some rotation but no flexion
What are the three kind of ribs and their number?
TRUE: 1-7
FALSE: 8-10
FLOATING: 11-12
Which are the typical ribs? What are their features?
3-10
- head with a ridge and two articular half-facets
- neck
- tubercle with an articular facet
- body/shaft
- costal angle
- costal groove
What are the features of rib 1?
- scalene tubercle
- groove for subclavian vein
- groove for subclavian artery
- single facet on head (no ridge)
- no costal groove
- shortest
- deep
What is the specificity of rib 2?
tuberosity for serratus anterior
What are the features of floating ribs?
- sharp ends
- only one round head with no ridge
- no tubercles
Name the three parts of the sternum.
manubrium, body, xiphisternum
How does the body of the sternum develop?
from 4 pieces of cartilage that ossify
Name 6 structures at the level of the sternal angle.
- 2nd costal cartilage
- intervertebral disc between T4 and T5
- proximal and distal boundaries of aortic arch
- bifurcation of the trachea
- SVC entering the heart
- superior limit of the pulmonary trunk
What is the solar plexus region?
most anterior part of the T6 dermatome
Describe the costovertebral joints of rib 2. Which rib(s) have the same arrangement?
articulates with superior costal facet of its corresponding vertebra and with the inferior facet of the vertebra above
synovial joint with ligaments
rib 3-10
Describe the number of facets for costovertebral joints on the left side of the body of vertebrae 1 to 12.
1 –> one full + one half (inferior)
2-9 –> 2 half
10 –> 1 half (superior)
11-12 –> 1 full
Which rib(s) do not have a costotransverse joint?
11 and 12
What type of joints are sternochondral joints?
synovial
What type of joints are costochondral joints?
primary cartilaginous (hyaline)
Which ribs have horizontal costal cartilage?
1 to 4
Name the boundaries of the thoracic inlet.
T1 vertebra + 1st rib and its costal cartilage + manubrium
What is the level of the most anterior part of the thoracic inlet?
T2/T3 intervertebral disc
Name the structures that pass between the thorax and the neck.
- vessels that supply and drain the head and neck
- trachea
- oesophagus
- vagus nerve
- recurrent laryngeal nerves
- phrenic nerves
Name the structures that pass between the thorax and the upper limb.
- subclavian vein
- subclavian artery
- inferior trunk of the brachial plexus
What are the boundaries of the thoracic outlet?
- T12 vertebra
- 11th and 12th ribs
- costal cartilages of ribs 7-10
- xiphoid process
What are the four main structures to pass from the thorax to the abdomen through the diaphragm?
- aorta
- inferior vena cava
- oesophagus
- phrenic nerve
Define Montgomery glands and tubercles.
MONTGOMERY GLANDS
sebaceous glands in the breast
MONTGOMERY TUBERCLES
the visible portions of Montgomery (areolar) glands on the skin surface within the areola
What is the position of the breast in adult females?
between the 2nd and the 6th or7th rib
How far could the axillary process of the breast extend to?
the apex of the axilla
Which muscles (excluding intercostals) are found underneath the breast?
- pectoralis major
- serratus anterior
- external oblique muscles
How do you call the condensations of connective tissue in the breast that connects the deep fascia to the dermis?
Cooper’s ligaments = suspensory ligaments of the breast
Define retromammary space.
layer of loose connective tissue between the deep layer of superficial fascia and the deep fascia
Which are the two main vessels that provide vascular supply to the breast and how?
- internal thoracic artery (through mammary branches and anterior intercostal arteries)
- axillary artery (through the lateral thoracic and thoracoacromial branches)
Explain the lymph drainage of the breast.
AREOLA + LATERAL QUADRANTS
axillary lymph nodes
MEDIAL QUADRANTS
parasternal lymph nodes and opposite breast
INFERIOR QUADRANTS
inferior phrenic lymph nodes
Which ribs are most commonly fractured?
3-10
Name 4 complications of rib fractures.
- haemothorax
- pneumothorax
- pulmonary injury
- splenic injury
In which direction do external intercostal fibers pull? What are the 2 functions of this muscle?
pull upwards
- prevent indrawing of ribs during inspiration
- aid inspiration
Where would you find the external intercostal membrane?
anteriorly
In which direction do internal intercostal fibers pull? What are the 2 functions of this muscle?
pull downwards
- prevent indrawing of ribs during inspiration
- aids elastic recoil at (forced) expiration
Where would you find the internal intercostal membrane?
posteriorly
Name three other intercostal muscles, and give their general function.
- innermost intercostal
- transversus thoracis
- subcostalis
aid forced expiration
The rule is that anterior rami of the thoracic spinal nerves do not form nerve plexuses and maintain their segmental orientation to become intercostal nerves. What are the exceptions?
T1 and lateral cutaneous branch of T2
What lies in the costal groove, from superior to inferior? Between which muscles are they situated?
Intercostal VAN:
Vein
Artery
Nerve
between internal and innermost intercostal muscles
What nerves, other than the intercostal ones, also supply the thoracic wall?
supraclavicular nerves (C3-4)
Which intercostal nerve has no cutaneous distribution over the thorax wall? What does it then supply?
T1
motor to intercostal muscles and small muscles of the hand
Which nerve is at risk in breast surgery?
T2
What else than the thorax wall do T7 to T12 supply?
skin and muscles of the abdominal wall
What do the ventral rami of T2-T11 supply in the thoracic wall?
- motor to intercostal muscles
- sensory to skin and parietal pleura
- carry sympathetics
At what level do the hemiazygos and accessory hemiazygos veins respectively usually cross?
Hemiazygos –> T9
Accessory hemiazygos -> T8
Where is located the beginning of the superior hemiazygos vein?
left 4th intercostal space
Which nodes receive lymph from the thorax wall first?
anteriorly: parasternal nodes
posteriorly: intercostal nodes
Give the 5 main functions of the cardiovascular system.
- bulk flow of materials
- temperature regulation
- homeostasis
- host defense
- reproduction
Give two intermediates by which the CNS affects regulation and integration of the cardiovascular system.
- autonomic nerves
- hormones
How much of the blood is respectively found in: the heart, the systemic circulation, and the pulmonary circulation at one time?
HEART 7%
SYSTEMIC 84%
PULMONARY 9%
Some vessels are called conductants, and other capacitants. Which are they?
conductants - arteries
capacitants - veins
At rest, how much blood is pumped every minute by the heart?
5L/min
Give 6 features of blood vessels that can vary, and one common feature to all.
VARIES
- number
- diameter
- wall thickness
- smooth muscle
- elastic tissue
- fibrous tissue
COMMON
endothelial lining
Compare the diameter of the aorta, to that of an arteriole, a capillary, a venule and the vena cava.
AORTA 25mm ARTERIOLE 30microns CAPILLARY 8 microns VENULE 20 microns VENA CAVA 30mm
Which of arteries and veins have the most compliance?
Veins
What group of organs receives the most blood flow at rest, and which group receives the least?
THE MOST: abdominal organs
THE LEAST: heart
What percentage of filling of the ventricle with blood is caused by active contraction of the atrium?
20%
What is the role of chordae tendinae?
active competence = prevent eversion of the atrioventricular cusps
What types of valves are the aortic and pulmonary valves?
tricuspid semilunar valves
Which valve out of the mitral valve and the aortic valve, is the most subject to stress and abrasion? Why?
Aortic: smaller opening with higher pressure
What are the respective roles of desmosomes and gap junctions in cardiac muscle?
DESMOSOMES secure adhesion (mechanical)
GAP JUNCTION electrical connectivity (functional)
Give 4 features of cardiac cells.
- striated
- connected via intercalated discs
- electrical connection through gap junctions
- desmosomes
What are the 4 means of conduction in cardiac muscle?
- functional syncitium
- conduction network
- pacemaker activity
- autonomic innervation
What percentage of cardiac fibers form the excitatory and conductive muscle fibers?
1%
What muscles lie on either side of the sternal notch?
left and right sternocleidomastoid
At what level does the sternal notch lie? What about the xiphisternal joint?
STERNAL NOTCH
T2/T3 intervertebral disc
XIPHISTERNUM
T8/T9 intervertebral disc
Respectively, at which dermatome do each of the sternal angle, the xiphisternal joint, the umbilicus and the suprapubic region lie?
STERNAL ANGLE: C5
XIPHISTERNAL JOINT: T6
UMBILICUS: T10
SUPRAPUBIC REGION: T12
What is the name of the membrane that separates the thoracic cavity from the neck? Where does this membrane attach to?
suprapleural membrane
attaches to the bones of the thoracic inlet
Name the two muscles that lie on either side of the trachea.
- sternohyoid
- sternothyroid
Which thoracic spinous process is most palpable?
T1
What is the point of greatest weakness of the rib?
angle of the rib
What are the two parts of a typical rib’s tubercle?
- articular facet for articulation with the transverse process of its corresponding vertebra
- roughened attachment of the lateral costotransverse ligament
What is the level of the manubrium? What about of the body of the sternum?
MANUBRIUM
T3 to T4
BODY OF STERNUM
T5 to T9
Why may the body of the sternum be perforated?
It develops as two halves that join together
By what age does the xiphisternum ossify?
40 years old
For which rib is the sternal angle a landmark?
rib 2
List the 3 major types of blood vessels.
- arteries
- capillaries
- veins
Name the 3 layers and 2 partitions of a basic blood vessel.
- tunica intima
- tunica media
- tunica adventitia
- internal elastic lamina
- external elastic lamina