Thoracic wall, Muscles and NVS (thorax part 1) Flashcards
Several imaginary lines are sometimes used to describe surface locations on the anterior and posterior chest walls.
Lines of Orientation
lies in the medial plane over the sternum
Midsternal line
runs vertically downward from the midpoint of the clavicle
midclavicular line
runs vertically downward from the anterior axillary fold
anterior axillary line
runs vertically downward from the posterior axillary fold
posterior axillary line
runs vertically downward from a point situated midway between the anterior and posterior axillary folds
midaxillary line
runs vertically downward on the posterior wall of the thorax, passing through the inferior angle of scapula (arms at the sides)
scapular line
What are the borders of the thoracic wall?
posteriorly - thoracic vertebral column anteriorly - sternum and costal cartilages laterally - ribs and intercostal spaces superiorly - suprapleural membrane inferiorly - diaphragm
What are formed between the ribs and costal cartilages?
costochondral (CC) joints
Which are true ribs?
ribs 1-7
Which are false ribs?
ribs 8-12
A flat bone and consists of the manubrium, the body, and the xiphoid process
sternum
How is the sternum of female compared to male?
shorter and thinner, body is more than twice as long as the manubrium in male, but is usually less in female
articulates with the cartilage of the first rib, the upper half of the second rib, and the body of the sternum at the manubriosternal joint, or sternal angle
Manubrium
What part of the manubrium can be readily palpated at the root of the neck?
jugular/suprasternal notch(T2) - superior margin, a depression on anterior neck
The junction between the manubrium and the body of the sternum
Sternal Angle (Angle of Louis)
What landmarks do the sternal angle involve?
a. The second ribs articulate with the sternum.
b. The aortic arch begins and ends.
c. The trachea bifurcates into the right and left bronchi at the carina.
d. The inferior border of the superior mediastinum is demarcated.
e. A transverse plane can pass through the intervertebral disk between T4 and T5.
What is the posterior landmark of sternal angle of Louis?
T4/ between T4 and T5
Articulates with the second to seventh costal cartilages
body of sternum
Where does body of sternum articulate at the xiphisternal joint?
xiphoid process
What is the posterior landmark for xiphisternal joint?
T9 vertebra
What is the posterior landmark for xiphoid process?
T10 vertebra
It marks the lower limit of the thoracic cavity in front, the upper surface of the liver, diaphragm, and lower border of the heart
T10 - Xiphoid process
Where can xiphoid process be palpated?
epigastrium
Where is xiphoid process attached via its caudal end to?
linea alba
What specific part of the rib or costal cartilages attach to the manubrium sternum?
Costal cartilage no. 1 and 2
the manubrium attachment to clavicle
facet for clavicle
Consist of 12 pairs of bones that form the main part of the thoracic cage, extending from the vertebrae to or toward the sternum
Ribs
What are typical ribs?
ribs 3 - 9
Increase the anteroposterior and transverse diameters of the thorax by their movements
Ribs
What are the parts of typical ribs?
head
neck
tubercle
body (shaft)
Where does head articulate with?
corresponding vertebral bodies and intervertebral disks and supraadjacent vertebral bodies
thin and flat and turns sharply anteriorly at the angle and has a costal groove that follows the inferior and internal surface of a rib and lodges the intercostal vessels and nerves
body (shaft)
What lodges the intercostal vessels and nerves?
costal groove
What surface is the thoracentesis performed?
superior surface of the rib
articulates with the transverse processes of the corresponding vertebrae, with the exception of ribs 11 and 12
tubercle of rib
How many facets does the typical head has?
2
a constricted portion situated between the head and the tubercle
Neck
Where does the rib turn anteriorly?
angle of rib
What characterizes the superior surface of the first rib?
Scalene tubercle
What attaches to the scalene tubercle?
anterior scalene muscle
What are the landmarks found in scalene tubercle?
two smooth grooves:
- anterior groove - posterior groove
What passes in the anterior and posterior grooves respectively?
anterior groove: subclavian vein
posterior groove: subclavian artery
The first seven ribs (ribs 1-7) which are attached to the sternum by their costal cartilages
True Ribs
The lower five ribs (ribs 8-12)
False Ribs
The last two ribs which are connected only to the vertebrae
Floating ribs (11-12)
don’t have directly attachment to the sternum; attached to costal cartilage above
ribs 8-10
Broadest and shortest of the true ribs
First Rib
Has a single articular facet on its head, which articulates with the first thoracic vertebra
First Rib
Has a scalene tubercle for the insertion of the anterior scalene muscle and two grooves for the subclavian artery and vein
First Rib
Has two articular facets on its head, which articulate with the bodies of the first and second thoracic vertebrae
Second Rib
About twice as long as the first rib
Second Rib
Has a single articular facet on its head, which articulates with the 10th thoracic vertebra
Tenth Rib
Have a single articular facet on their heads and no neck or tubercle
Eleventh and Twelfth Ribs
Bars of cartilage connecting the upper seven ribs to the lateral edge of the sternum and the 8th, 9th, and 10th ribs to the cartilage immediately above
Costal Cartilages
Where do the cartilages of 11th and 12th ribs end?
abdominal musculature
contribute significantly to the elasticity and mobility of the thoracic walls
Costal Cartilages
In old age, the costal cartilages tend to lose some of their flexibility as the result of
superficial calcification
where is the costal groove?
internal and inferior
Where is the intercostal space of a certain rib?
below the corresponding rib
Increase transverse diameter of rib cage
Bucket Handle Motion
Where does bucket handle motion occur?
Lower ribs (6-10)
Increase anteroposterior (A-P) diameter of rib cage
Pump Handle Motion
Where does Pump Handle Motion occur?
Upper ribs
The chest cavity communicates with the roof of the neck through an opening
thoracic outlet
Why is thoracic outlet called an outlet?
because important vessels and nerves emerge from the thorax here to enter the neck and upper limbs.
What are the borders of the thoracic outlet?
posteriorly - T1 vertebra
laterally - medial borders of the 1st ribs and their costal cartilages
anteriorly - superior border of the manubrium sterni
How does the thoracic cavity communicate with the abdomen?
through a large opening
What are the boundaries of the large opening in the thoracic cavity and abdomen?
posteriorly - 12th thoracic vertebra
laterally - curving costal margin
anteriorly - xiphisternal joint
Through this large opening, which is closed by the __, pass the esophagus and many large vessels and nerves, all of which pierce the __
diaphragm (1&2)
The compression of neurovascular structures in the thoracic outlet
Thoracic outlet syndrome
What causes Thoracic outlet syndrome?
by pressure on the brachial plexuses by a cervical rib; or
could be cancer, mass lesion
Compression on the neurovascular bundle occur as a result of cervical ribs or abnormal insertions of the anterior and middle scalene muscles. What are the abnormal insertions?
congenital anomaly where they have extra rib in cervical region
A saddle-type synovial joint with two separate synovial cavities and provides the only bony attachment between the appendicular and axial skeletons
Sternoclavicular Joint
The articulation of the sternum with the first seven cartilages. The sternum (manubrium) forms synchondrosis with the first costal cartilage, whereas the second to seventh costal cartilages form synovial plane joints with the sternum
Sternocostal (Sternochondral) Joints
Synchondroses in which the ribs articulate with their respective costal cartilages
Costochondral Joints (CC)
Symphysis (secondary cartilaginous joint) between manubrium and body of sternum
Manubriosternal Joint
Synchondrosis articulation between xiphoid process and body of the sternum
Xiphisternal Joint
Synovial plane joints of heads of ribs when corresponding and supraadjacent vertebral bodies
Costovertebral Joints
Synovial plane joint of tubercle of rib with transverse process of corresponding vertebra
Costotransverse Joint
Synovial plane joints between 6th and 10th costal cartilages of ribs
Interchondral Joints
The spaces between the ribs contain three muscles of respiration. What are those?
external intercostal
internal intercostal
innermost intercostal muscle.
where do the intercostal nerves and blood vessels run?
between the intermediate muscles of
- (internal
intercostal and
innermost
intercostal
muscle)
and deepest layers of musclesHow are the intercostal nerves and blood vessels arranged?
above to downward: intercostal vein, intercostal artery, and intercostal nerve (VAN).
Where is the origin of external intercostals, internal intercostals, and innermost intercostals muscles?
Lower border of ribs
Where is the insertion of external intercostals, internal intercostals, and innermost intercostals muscles?
Upper border of rib below
What is the nerve supply of external intercostals, internal intercostals, and innermost intercostals muscles?
Intercostal Nerve
What is the action of external intercostal muscle?
Elevates ribs in inspiration
What is the action of internal intercostal muscle?
Depresses rib (costal part); (expiration) elevate ribs (interchondral part)
What is the action of innermost internal intercostal muscle?
Elevates ribs (inspiration)
Transversus thoracis action
Depresses ribs (expiration)
Subcostalis action
Elevates ribs (inspiration)
Levator costarum action
Elevates ribs (inspiration)
What are the anterior primary rami of the first 11 thoracic spinal nerves?
Intercostal Nerves
What is the anterior primary ramus of the 12th thoracic spinal nerve?
subcostal nerve
Run between the internal and innermost layers of muscles, with the intercostal veins and arteries above
Intercostal Nerves
What are lodged in the costal grooves ?
Intercostal Nerves
Give rise to lateral and anterior cutaneous branches and muscular branches
Intercostal Nerves
What is joined to the brachial plexus by a large branch that is equivalent to the lateral cutaneous branch of typical intercostal nerves?
first intercostal nerve (T1)
What comprises the brachial plexus?
C1-C8
T1
What is joined to the medial cutaneous nerve of the arm by a branch called the intercostobrachial nerve, which is equivalent to the lateral cutaneous branch of the other nerves?
second intercostal nerve (T2)
What does second intercostal nerve (T2) supply?
skin of the armpit and the upper medial side of the arm.
What disease is associated with pain to the medial side of the arm?
coronary artery disease
Usually arises from the first part of the subclavian artery and descends directly behind the first six costal cartilages, just lateral to the sternum
Internal Thoracic Artery
Gives rise to two anterior intercostal arteries in each of the upper six intercostal spaces and terminates at the sixth intercostal space by dividing into the musculophrenic and superior epigastric arteries
Internal Thoracic Artery
Accompanies the phrenic nerve between the pleura and the pericardium to the diaphragm
Pericardiophrenic Artery
Supplies the pleura, pericardium, and diaphragm (upper surface)
Pericardiophrenic Artery
Are 12 small arteries, 2 in each of the upper 6 intercostal spaces that run laterally, one each at the upper and lower borders of each space.
Anterior Intercostal Arteries
The upper artery of anterior intercostal arteries in each intercostal space anastomoses with the _____ and the lower one joins the ____of the posterior intercostal artery
posterior intercostal artery
collateral branch
Provide muscular branches to the intercostal, serratus anterior, and pectoral muscles
Anterior Intercostal Arteries
Where does Anterior Intercostal Arteries arise from?
internal thoracic artery
Where does the the posterior intercostal artery originate?
thoracic aorta
Where is posterior intercostal artery found?
3-11
Perforate the internal intercostal muscles in the upper six intercostal spaces, course with the anterior cutaneous branches of the intercostal nerves, and supply the pectoralis major muscle and the skin and subcutaneous tissue over it
Anterior Perforating Branches
What does Anterior Perforating Branches provide?
medial mammary branches (second, third, and fourth branches)
Follows the costal arch on the inner surface of the costal cartilages and gives rise to two anterior arteries in the seventh, eighth, and ninth spaces; perforates the diaphragm; and ends in the 10th intercostal space, where it anastomoses with the deep circumflex iliac artery
Musculophrenic Artery
It supplies the pericardium, diaphragm, and muscles of the abdominal wall
Musculophrenic Artery
Descends on the deep surface of the rectus abdominis muscle within the rectus sheath; supplies this muscle and anastomoses with the inferior epigastric artery
Superior Epigastric Artery
It supplies the diaphragm, peritoneum, and anterior abdominal wall
Superior Epigastric Artery
What vessels are medially and laterally located to scalene anterior muscle?
MEDIAL - Subclavian artery
LATERAL - Subclavian vein
Subclavian artery is divided into three by the scalene anterior. What are those?
MEDIAL - 1ST PART
POSTERIOR - 2ND PART
LATERAL - 3RD PART
What vessels (branches) originate from the first part of subclavian artery?
Internal thoracic artery
Vertebral artery
Thyrocervical trunk
What does Superior intercostal artery gives branches to?
Posterior intercostal artery (upper two intercostal spaces)
Formed by the confluence of the superior epigastric and musculophrenic veins, ascends on the medial side of the artery, receives the upper six anterior intercostal and pericardiophrenic veins and ends in the brachiocephalic vein.
Internal Thoracic Vein
A venous connection between the lateral thoracic vein and the superficial epigastric vein
Thoracoepigastric Vein
Where does the posterior intercostal vein drain?
azygos or hemiazygos vein
Where does anterior intercostal vein drain?
internal thoracic vein and musculophrenic vein
- Placed along the internal thoracic artery
- Receive lymph from the medial portion of the breast, intercostal spaces, diaphragm, and supraumbilical region of the abdominal wall
- Drain into the junction of the internal jugular and subclavian veins
Sternal or Parasternal (Internal Thoracic) Nodes
- Lie near the heads of the ribs
- Receive lymph from the intercostal spaces and the pleura
- Drain into the cisterna chyli or the thoracic duct
Intercostal Nodes
- Lie on the thoracic surface of the diaphragm
- Receive lymph from the pericardium, diaphragm, and liver
- Drain into the sternal and posterior mediastinal nodes
Phrenic Nodes
It is the structure involved when the outlet is closed by a dense fascial layer (thickening of the endothoracic fascia).
suprapleural membrane
It is attached at its apex to the tip of the transverse process of the seventh cervical vertebra and medially to the fascia investing the structures passing from the thorax into the neck.
suprapleural membrane
It protects the underlying cervical pleura and resists the changes in intrathoracic pressure occurring during respiratory movements.
suprapleural membrane
a thin layer of loose connective tissue that separates the parietal pleura from the thoracic wall. The suprapleural membrane is a thickening of this fascia.
Endothoracic Fascia
What branches originate from the 2nd part of subclavian artery?
Costocervical
Dorsal scapular
What branches originate from the 3rd part of subclavian artery?
None
