Thorax Flashcards
The intercostal nerves, arteries, and veins are positioned ______ to the _______ __________ muscles.
Deep; Internal intecostal
The intercostal nerves, arteries, and veins are all positioned directly _________ to the ribs.
inferior
The internal thoracic artery is positioned _____________ to the first six costal cartilages.
posterior (deep)
What are the attachments of the external intercostal muscles?
From rib to rib oriented from superior-lateral to inferior-medial (down and in)
What are the actions of the external intercostal muscles?
elevation of ribs
What is the innervations of the external intercostal muscles?
Intercostal nerves (segmental)
What are the muscles of the thorax?
External intercostals, internal & innermost intercostals, transversus thoracic, and diaphragm
What are the attachments of the internal and innermost intercostal muscles?
From rib to rib oriented superior-medial to inferior-lateral (down and out)
What are the actions of the internal and innermost intercostal muscles?
depression of ribs
What is the innervation of the internal and innermost intercostal muscles?
intercostal nerves (segmental)
What are the attachments of the transversus thoracic muscle?
from posterior sternum to costal cartilages
What are the actions of the transversus thoracic muscle?
depress ribs
What is the innervation of the transversus thoracic muscle?
intercostal nerves (segmental)
What are the attachments of the diaphragm muscle?
from the xiphoid process, inner surface of the lower ribs & costal cartilages, lumbar vertebrae via the crura to the central tendon
What are the actions of the diaphragm muscle?
inspiration (negative thoracic pressure by inferior displacement)
What are the innervation and spinal segments of the diaphragm muscle?
phrenic nerve
C3 - C5
What houses the intercostal vein, artery, and nerve?
the costal groove of the shaft of the ribs
The grooves of which rib house the subclavian artery and vein?
first rib
Name the boundaries and general contents of the thoracic cavity
Posterior: Spine
Anterior: Sternum
Inferior: Diaphragm
Superior: Superior Thoracic Aperture (opening between the 1st rib, vertebral column, and sternum)
Contains primarily organs of the respiratory and cardiovascular systems
Name the compartments of the thoracic cavity
Superior mediastinum
Right pleural cavity (R lung)
Left pleural cavity (L lung)
Inferior mediastinum
Describe the components and functions of the thoracic wall
Composed of skin, subcutaneous tissue, ribs, intercostal muscles
Functions: protection, respiration, and muscle attachment
Where is the thoracic wall located?
outside of the thoracic cavity
What are the three different types of ribs?
True 1-7
False 8-10
Floating 11, 12
What makes a rib a “true” rib?
direct cartilaginous attachment to the sternum
What makes a rib a “false” rib?
Indirect connection to the sternum (the costal cartilage coalesce prior to attaching to the sternum)
What makes a rib a “floating” rib?
No attachment to the sternum
Describe the general structure of a rib.
A single thoracic vertebra articulates with a pair of ribs.
Most medially is the head of the rib, then a neck, a costal tubercle, a costal angle (the sharp bending of the rib from medio/lateral to anterior/posterior), the shaft of the rib which then connects to the sternum via cartilage
Name the three rib joints and their synovial classification.
Costovertebral (head of rib to the vertebral body)
Costotransverse (costal tubercle to the transverse process)
Sternocostal (sternum to costal cartilage)
All plane or gliding classification
Explain the unique landmarks of the first rib
Scalene tubercle - a swelling as a result of the attachment to the anterior scalene muscle
Groove for subclavian artery (posterior to tubercle)
Groove for the subclavian vein (anterior to tubercle)
Describe the unique landmarks of the sternum
Formed from 3 separate pieces that have fused
Manubrium
Body
Xiphoid process
Subclavian vein is __________ to subclavian artery,
anterior
What are the bony features of the manubrium of the sternum?
Jugular notch and clavicular notch/facet
What are the bony features of the body of the sternum?
Sternal angle (interphase joint between manubrium and the body), costal notches/facets
Where does the second rib attach to the sternum?
sternal angle between manubrium and body of the sternum
The neurovasculature is positioned _________ the innermost intercostal muscle and the internal intercostal muscle.
between
What are the respiratory movements during inspiration and respiration for the medial &lateral dimensions?
Inspiration:
Ribs elevate and move the middle of shaft laterally (bucket handle) resulting in a larger thoracic cavity laterally
Expiration:
Ribs depress and move middle of shaft medially resulting in a reduction in the size of the thoracic cavity
What are the respiratory movements during inspiration and respiration for the anterior & posterior dimensions?
Inspiration:
Ribs elevate and move sternum upward and forward (pump handle)
Expiration:
Ribs depress and move sternum downard and backward reducing the thoracic cavity volume
What is the goal of respiration?
Decrease volume of the thoracic cavity
What is the goal inspiration?
Increase volume of the thoracic cavity
An intercostal nerve is another name for the __________ of a thoracic spinal nerve.
Ventral ramus
Describe the naming convention of the intercostal nerves T1-T12.
Intercostal nn. (T1-6)
Upper intercostal nn,
Thoracoabdominal nn. (T2-11)
Lower intercostal nn.
Subcostal n. (T12)
The subcostal nerve is found ________ to the 12th rib.
inferior
The subcostal nerve is the _________ of the 12th thoracic spinal nerve.
Ventral ramus
What structure serves as a boundary between the thoracic and abdominal cavities?
Diaphragm
The 9th rib has indirect cartilaginous attachment to the sternum, making it what type of rib?
False
What rib joint is formed between the head of the rib and the body of the vertebra?
Costovertebral
What bony landmark is formed at the union of the manubrium and body of the sternum?
Sternal angle
What dermatome of the thorax corresponds to skin over the xiphoid process?
T6
What are the functions and spinal segments of the phrenic nerve?
C3-5
Provides sensory & postganglionic sympathetic innervation to the pericardium & central tendon (& adjacent pleura & peritoneum)
Provides motor & postganglionic sympathetic innervation to the diaphragm
During contraction, the diaphragm muscle becomes very ______ and ________ displaced.
flat; inferiorly
What are the respiratory movements during inspiration and respiration for the vertical dimension?
Inspiration: The diaphragm contracts/displaces inferiorly (depression) allowing the thoracic cavity to enlarge.
Expiration: Diaphragm relaxes and returns to domelike shape, so air is forced out of the lungs d/t reduced size in cavity.
What are the three dimensions of if respiratory movement?
Vertical
Medial/Lateral
Anterior/Posterior
What are the functions and spinal segments of the subcostal nerve?
T12
Provides sensory & postganglionic sympathetic innervations to the skin overlying the lateral and anterior abdominal wall & muscles of the anterior abdominal wall
Provides motor innervation to muscles of the anterior abdominal wall
What are the 5 thoracic spinal nerves, and do they branch from the dorsal or ventral primary rami.
Ventral primary rami: intercostal, thoracoabdominal, and subcostal nerves
Dorsal primary rami: medial branch and lateral branch
What are the functions of the medial branch of the dorsal primary ramus?
Provide sensory & postganglionic sympathetic innervation to the back muscles & overlying skin
Provides motor innervation of the midline of the deep back muscles and facet joints
What are the functions of the lateral branch of the dorsal primary ramus?
Provide sensory & postganglionic sympathetic innervation to the back muscles & overlying skin
Provides motor innervation of deep and superficial back muscles.
What are the functions, spinal segments, and branches of the intercostal nerves?
T1-6
Provides sensory & postganglionic sympathetic innervation to intercostal muscles, parietal pleura & skin,
Provides motor innervation to intercostal muscles
Branches: Lateral cutaneous br Anterior cutaneous br Collateral br Intercostobrachial nerve (T2 only)
What are the functions of the lateral cutaneous branch of the intercostal nerves?
Sensory & postganglionic sympathetic innervation of skin overlying the lateral aspect of intercostal space
What are the functions of the anterior cutaneous branch of the intercostal nerves?
Sensory & postganglionic sympathetic innervation of skin overlying the anterior aspect of intercostal space
What are the functions of the collateral branch of the intercostal nerves?
redundant with the remainder of nerve
[not sure what this means, but it’s off the structure info list]
What are the functions and spinal segments of the intercostobrachial nerve? Where does it branch off?
Sensory & postganglionic sympathetic innervation of skin overlying proximal & medial aspect of arm
T2 only
Branches off the upper intercostal nerves
What are the functions, spinal segments, and branches of the thoracoabdominal nerves?
T7-11
Sensory & postganglionic sympathetic innervation to intercostal muscles, anterio abdominal muscles, peripheral diaphragm, and parietal pleura
Motor innervation of intercostal muscles and muscles of anterior abdominal wall
Branches:
Lateral cutaneous br
Anterior cutaneous br
Collateral br
Upper intercostals nerves are also known as ___________.
Intercostal nerves
Lower intercostal nerves are also known as ____________.
Thoracoabdominal
What is the function of the lateral cutaneous branch of the thoracoabdominal nerves?
Sensory & postganglionic sympathetic innervation of skin overlying the lateral aspect of intercostal space & adjacent anterior abdominal wall
What is the function of the anterior cutaneous branch of the thoracoabdominal nerves?
Sensory & postganglionic sympathetic innervation of skin overlying the rectus abdominis muscle
What is the function of the collateral branch of the thoracoabdominal nerves?
Redundant with remainder of nerve
What dermatome of the thorax corresponds to skin over the nipple?
T4
What dermatome of the thorax corresponds to skin over the umbilicus?
T10
