Pectoral Region Flashcards
What fascia is the pectoral fascia continuos with?
Anterior abdominal wall fascia and brachial fascia
-leaves lateral border of pectorals major m. to become axillary fascia
What fascia encloses subclavius m. and pectorals minor m.?
Clavipectoral fascia
What pierces the costocoracoid membrane?
Lateral pectoral n., cephalic v., and thoracoacromial trunk.
What does the suspensory l. of the axilla do?
Supports axillary fascia and pulls axillary fascia and skin inferior to it upward during ABD
-Forms axillary fossa
What are the anterior axioappendicular muscles?
- Pectoralis major
- Pectoralis minor
- Subclavius
- Serratus Anterior
What groove contains the cephalic vain?
Deltopectoral groove
What are the borders of the Clavipectoral (deltopectoral) triangle?
Superiorly - clavicle
Medially - pectoralis m.
Laterally - deltoid m.
What does the Clavipectoral (deltopectoral) triangle contain?
- Cephalic v. piercing clavipectoral fascia and entering axillary v.
- Tip of coracoid process laterally
- Branches of thoracoacromial trunk
Pectoralis major
O: Calvicular head - anterior surface of medal 1/2 of clavicle. Sternal head - anterior surface of sternum, superior 6 costal cartilages, aponeurosis of external oblique m.
I: Lateral lip of IT groove of humerus
A: ADD, MR of humerus; independently: Clavicular head - flexes humerus. Sternal head - extends from flexed position.
N: Medial and lateral pectoral NN. (Clavicular head - C5, C6, Sternal head- C7, C8, T1)
B: pectoral branches of thoracoacromial trunk
Pectoralis minor
O: 3-5th ribs (sometimes 6th) near costal cartilages
I: medial border and superior surface coracoid process.
A: Stabilizes scapula by drawing it anterior and inferior against thoracic wall; accessory m. of inspiration.
N: Medial pectoral n. (C8, T1)
B: Pectoral branches from thoracoacromial trunk
*divides axillary into it’s 3 parts
Subclavius
O: Junction of 1st rib and its costal cartilage
I: inferior surface, middle 1/3 of clavicle
A: Anchors and depresses clavicle
N: nerve to subclavius (C5, C6)
B: Clavicular branches of thoracoacromial trunk
Serratus anterior
O: Exertnal surfaces of lateral parts of 1st-8th ribs (sometimes 9th)
I: Anterior surface of medal border of scapula
A: Scapular protraction and upward rotation; fixes scapula against thoracic wall
N: Long thoracic n (C5, C6, C7)
B: Superior and lateral thoracic aa.f
What are the arteries of the axioappendicular muscles and what do each supply?
-Superior thoracic a - from 1st part of axillary a. (supplies superior part of serratus anterior m.)
-Lateral thoracic a. - from 2nd part of axillary a.
(supplies serratus anterior m.)
-Thoracoacromial trunk - from 2nd part of axillary a. (gives of clavicular, acromial, deltoid and pectoral branches)
What is the veins of the axioappendicular muscles?
Cephalic v. :
- formed on dorsum of hand
- ascends in subcutaneous tissue
- superiorly, found in deltopectoral groove
- enters clavipectoral triangle
- drains into terminal part of axillary v.
What innervates the axioappendicular muscles?
- N. to subclavius: from superior trunk of brachial plexus (supplies subclavius m.)
- Long thoracic n. : from VPR of C5, C6, C7 supplying the serratus anterior m.
- Lateral pectoral n. - from lateral cord of brachial plexus, supplies pectorals major m. on its deep surface.
- Medial pectoral n. - from medial cord of brachial plexus piercing pectorals minor m. and enters deep surface of pectorals major m. Supplies pectorals minor m. and sternal head of pectoralis major m.
