Axilla and Pectoral Region Lecture Flashcards Preview

Human Anatomy 1 -- Zach H. > Axilla and Pectoral Region Lecture > Flashcards

Flashcards in Axilla and Pectoral Region Lecture Deck (72):

What bones are found in the pectoral region?

  • clavicles 
  • sternum
    • manubrium
    • body 
    • xiphoid 
  • ribs 
  • scapula 


Which two bones do the ribs articulate with?

  • sternum 
  • vertebrae 


Which ribs are "atypical"?

ribs 1,2, 11, and 12 are "atypical"


Which ribs are "true" ribs (vertebrocostal)?

ribs 1-7 are "true' ribs 


Which ribs are "false" ribs (vertebrochondral)?

ribs 8-10 are "false" ribs


Which ribs are considered "floating" ribs? 

ribs 11 and 12 are "floating" ribs 


What does the tubercle and the head of the rib articulate with? 

  • Tubercle articulates with transverse process. 
  • Head articulates with superior and inferior articulate processes. 


Which named parts of the rib are found at the vertebral end? 

  • head 
  • neck 
  • tubercle 
  • angle 


What does the sternal end of the rib articulate with? 

articulates directly with sternum, costal carilage, or sits in fascia. 


What runs in the costal groove of the rib? 

Neurovascular Bundle 


True or False:

Mammary glands are modified sweat glands. 



What is retromammary space?

Potential space between breast and pectoral fascia. 


What is the breast innervated by? 

Intercostal nerves (4th-6th) 


What attaches the breasat to the dermis of overlying skin? 

Suspensory Ligaments (Cooper's Ligaments)


How many lactiferous ducts open at the nipple in a typical breast? 

15-20 lactiferous ducts open at nipple, which is surrounded by pigmented areola


What is the arterial supply to the breast?

  • mammary branches from: 
    • anterior intercostal artery 
    • lateral thoracic artery
    • internal thoracic artery


What nerves innervate the superior portion of the breast? 

supraclavicular nerve


What is the venous drainage of the breast? 

  • mainly to axillary vein via lateral thoracic veins and medial mammary veins
    • lateral thoracic vein 
    • medial mammary vein 
  • some drainage to internal thoracic vein via anterior intercostal veins 


Which lymph nodes drain the nipple, areola, and lactiferous lobules?

subareolar lymph nodes 


Which lymph nodes drain > 75% of lymph from the breast? 

  • axillary lymph nodes 
    • pectoral 
    • central 
    • apical


Which two types of lymph nodes drain the remaining lymph from the breast? 

  • parasternal lymph nodes 
  • abdominal lymph nodes 


What innervates the breast tissue?

  • mainly from anterior and lateral branches of 4th-6th intercostal nerves 
  • may also receive some innervation from supraclavicular nerve brahces as well as branches of other intercostal nerves. 


What is polymastia and polythelia?

An extra breast or nipple. Supernumerary breasts or nipples. 


What is the border of the deltopectoral (clavipectoral) triangle?

  • Deltoid
  • Pectoralis Major
  • Middle 1/3 of Clavicle 


What vein, artery, and lymph node is found in the deltopectoral (clavipectoral) triangle? 

  • vein = cephalic vein 
  • artery = deltoid branch of thoracoacromial artery 
    • from axillary artery
  • lymph node = deltopectoral lymph nodes 


What muscle is invested within the clavipectoral fascia?

  • subclavius 
  • pectoralis minor 


What does the clavipectoral fascia attach to? 

  • clavicle 
  • anterior thoracic wall 


What vein, artery, and nerves pierce the clavipectoral fascia? 

  • vein = cephalic vein 
  • artery = thoracoacromial artery 
  • nerves = lateral pectoral nerves 


What ligment does the clavipectoral fascia turn into? 

Becomes suspensory ligament of axilla. 


Which ligament attaches the clavipectoral fascia and axillary fascia? 

  • Suspensory Ligament of Axilla 


What muscles make up the pectoral region? 

  • pectoralis major 
  • subclavius 
  • pectoralis minor 
  • serratus anterior 


True of False:

The fascia of the pectoral region consists of superficial and deep layers that define borders, invest muscles, and create potential spaces. 



What is found in/under the superficial fascia in the pectoral region?

  • platysma 
  • supraclavicular nerves 
  • anterior and lateral branches of intercostal nerves 


Do the anterior and lateral branches of intercostal nerves that are found in the superficial fascia of the pectoral region innervate the pectoralis major?



Which two muscles in the pectoral region are separated by clavipectoral fascia? Also, which one of these muscles in completey incased in clavipectoral fascia? 

  • Pectoralis major and minor are separated by clavipectoral fascia. 
  • The pectoralis minor is covered in clavipectoral fascia. 


What is the proximal and distal attachment of the pectoralis major? 

Proximal (origin) Attachment: 

  • clavicular and sternocostal attachments 
    • anterior surface of medial 1/2 of clavicle 
    • anterior surface of sternum and superior 6 costal cartilages 

Distal (insertion) Attachment:

  • lateral lip of intertubercular sulcus (bicipital groove)


What are the actions of the pectoralis major?


  • adducts and medial rotates humerus 
  • draws scapula anteriorly and inferiorly (via clavicle)
  • clavicular portion flexes humerus 
  • sternal portion can extend humerus while it is in this flexed position 


What is the blood supply and innervation to the pectoralis major? 

Blood Supply:

  • pectoral branch(es) of thoracoacromial arterila trunk


  • lateral and medial pectoral nerves 
    • C5
    • C6 clavicular portion
    • C7
    • C8
    • T1 sternocostal portion 


True or False:

The medial and lateral pectoral nerves are NOT named for their position on the anterior thorax, but rather they are named forthe part of the rachial plexus that they come from.



Which cord of the brachial plexus does the medial pectoral nerve arise from? 

medial cord 


Which cord does the lateral pectoral nerve arise from on the brachial plexus?

lateral cord 


What is the proximal and distal attachments of the pectoralis minor? 

Proximal (origin) Attachment:

  • 3rd-5th ribs, near coastal cartilages 

Distal (insertion) Attachment: 

  • coracoid process of scapula 


What are the actions of the pectoralis minor? 


  • stabilizes scapula by pulling it anteriorly and inferiorly against posterior thoracic wall 


What is the blood supply and innervation of the pectoralis minor? 

Blood Supply:

  • pectoral branch(es) of thoracoacromial arterial trunk 


  • medial pectoral nerve (C8, T1) 
    • it is usually pierced by this nerve 


What is the proximal/distal attachment, actions, blood supply, and innervation of the subclavius? 

Proximal (origin) Attachment: 

  • junction of 1st rib and its costal cartilage 

Distal (insertion) Attachment: 

  • inferior surface of middle 1/3 of clavicle 


  • anchors clavicle 
  • depresses clavicle 

Blood Supply: 

  • clavicular branch(es) of thoracoacromial arterial trunk


  • nerve to subclavius (C5, C6) 


Which trunk does the nerve to subclavius come off of? 

upper trunk of brachial plexus 


What is the proximal/distal attachment, actions, blood supply, and innervation to the serratus anterior? 

Proximal (origin) Attachment:

  • external surfaces of lateral parts of ribs 1-9

Distal (insertion) Attachment:

  • anterior surface of medial border of scapula 


  • protracts scapula
  • rotates scapula
  • holds scapula against thorax 

Blood Supply:

  • lateral thoracic artery 


  • long thoracic nerve (C5, C6, C7) 


Does the long thoracic nerve come off of a trunk or root of the brachial plexus? 



Subclavian Artery

  • right: brachiocephalic trunk 
  • Left: aortic arch 
  • arises posterior to ternoclavicular joint 
  • usually has 3 "divisions" in relation to anterior scalene muscle
    • Part 1 -> is mdial to the anterior scalene muscle 
    • Part 2 -> is posterior to the anterior scalene muscle 
    • Part 3 -> is lateral to the anterior scalene muscle 


What are the 3 commonly found branches of the medial part (1) of the subclavian artery? 

  1. internal thoracic (mammary) artery
  2. vertebral artery 
  3. thyrocervical arterial trunk 


You know that the thyrocervical arterial trunk is one of the 3 arteries that branches off of the medial part of the subclavian artery, but what arteries come off of the thyrocervical arterial trunk?

  1. transverse cervical artery
    • superficial branch 
    • deep branch (dorsal scapular artery)
    • NOTE: the superficial and deep ranches of the t.c.a may arise independently. When they do form an arterial trunk, this structure is referred to as the cervicodorsal trunk. 
  2. inferior thyroid artery 
  3. ascending cervical artery 
  4. suprascapular artery 


Which artery is commonly found branching off of the posterior part (2) of the subclavian artery? 

  • costocervical arterial trunk
    • supreme intercostal artery 
    • deep cervical artery 


True or False: 

The lateral part (3) of the subclavian artery typically may have no branches, however, the dorsal scapular artery may arise independently from this part of the subclavian artery. 



At which land mark does the subclavian artery become the axillary artery? 

Lateral Border of First Rib 


Note Regarding the dorsal scapular artery....

The dorsal scapular artery can arise from either some part of the subclavian artery (usually the 3rd) or from the transverse cervical artery (about 30% ofthe time, and in this case it is called the "deep branch of the transverse cervical artery". 


Either way, the artery that runs along the vertebral border of the scapula is always referred to as the dorsal scapular artery


Which artery comes off of part 1 of the axillary artery?

Part 1

  • superior thoracic artery 


What arteries branch off of part 2 of the axillary artery? 

Part 2 

  • thoracoacromial trunk 
    • pectoral branch 
    • deltoid branch 
    • acromial branch 
    • clavicular branch 


Which arteries branch off of part 3 of the axillary artery? 

Part 3 

  • subscapular artery
    • circumflex scapular 
    • thoracodorsal 
  • anterior circumflex humeral 
  • posterior circumflex humeral 


True or False: 

The anterior circumflex humeral artery is typically twice as big as the posterior circumflex humeral artery. 

False - posterior circumflex humeral artery is typically twice as big as the anterior circumflex humeral artery. 


Which arteries contribute to the anastomosing arterial branches of the scapular anastomoses? 

  1. suprascapular artery (from subclavian artery) 
  2. dorsal scapular artery
    • (deep branch of transverse cervical artery from subclavian artery)
  3. posterior intercostal arteries (from thoracic aorta)
  4. circumflex scapular artery
    • (division of subscapular artery from axillary artery) 
  5. thoracodorsal artery (division of subscapular artery from axillary artery)


** Dr. K Wright recommended reading the blue box in COA about the scapular anastomoses. ** 


True or False: 

In certain cases or injury to, or ligation or occlusion of the axillary artery superior to the subscapular artery, direction of blood flow in the subscapular artery is reversed, allowing blood to flow to the distal portion of he axillary artery and the rest of the arm, forearm and hand. (talking about scapular anastomoses)


What does the basiic vein continue as to drain the arm? 

continues as the axillary vein 


What does the cephalic vein drain into before it becomes the subclavian vein? 

drains into axillary vein before it becomes subclavian vein


What makes up the apex of the boundary of the axilla? 


  • clavicle 
  • scapula 
  • 1st rib 


What makes up the base of the boundary of the axilla? 


  • skin and superficial fascia 
  • anterior axillary fold
    • pectoralis major
  • posterior axillary fold 
    • latissimus dorsi 
    • teres major 
  • chest wall 
    • serratus anterior 


What makes up the anterior wall of the boundary of the axilla? 

Anterior Wall: 

  • clavicle 
  • subclavius 
  • pectoralis major 
  • pectoralis minor 


What makes up the posterior wall of the boundary of the axilla? 

Posterior Wall: 

  • scapula 
  • subscapularis 
  • latissimus dorsi 
  • teres major 


What are the lateral structures that make up the boundaries of the axilla? 

Lateral Structures: 

  • intertubercular sulcus (bicipital groove) 
  • tendon of long head of biceps 
  • coracobrachialis tendon 


In a saggital section of the axilla, what axillary lymph nodes are found? 

  • central lymph nodes 
  • pectoral lymph nodes 


Does the lateral or medial pectoral nerve pierce the pectoralis minor? 

medial pectoral nerve 


Does the lateral pectoral nerve pierce the pectoralis minor? 

No, it pierces the clavipectoral fascia on the way to innervate the pectoralis major.