The Pectoral Region Flashcards
How many Ribs Join the Sternum?
1st Seven Ribs join the sternum
How many Ribs is there?
24 ribs, 12 on each side
Where does the sternal angle lie?
Mid-Clavicular line, 2nd intercostal space (T4, T5)
Where is the lower costal margin?
bottom edge of the ribcage, beneath ribs 8,9 and 10
Which ribs are the ‘false ribs’?
Ribs 8,9 and 10
Which ribs are the ‘floating ribs’?
11 and 12, they do not have an anterior attachment
What are the four main muscles of the pectoral region?
pectoralis major, pectorlais minor, serratus anterior and subclavius
What are the origins of Pectoralis major?
Sternal Head: cartilages of ribs 2-6, Clavicular head: medial half of the clavicle
What is the Insertion of Pectoralis major?
Lateral lip of the intertubercular groove of the humerus or crest of greater tubercle
What is the action of Pectoralis major?
Flexion, adduction and medial rotation of the shoulder. It also aids with breathing, pulls ribcage to create room for lung expansion.
What is the innervation of Pectoralis major?
C5-T1 pectoral nerves (lateral and medial)
What is the origin of Pectoralis Minor?
Anterior surfaces of the sternal ends of ribs 3-5
What is the insertion of Pectoralis Minor?
Coracoid process of the scapula
What is the action of the Pectoralis Minor?
Draws scapula forward and down
What is the innervation of Pectoralis Minor?
Medial Pectoral nerve C8,T1
What is the origin of serratus anterior?
Anterior surface of the first 8 ribs
What is the insertion of serratus anterior?
Anterior surface of the medial border of the scapula
What are the articulations of the Clavicle?
Acromioclavicular joint and sternoclavicular joint
How does Breast Cancer Spread?
Via lymph drainage to regional lymph nodes (thoracic lymph nodes- medial to the nipple and lymph nodes of the axilla- lateral breast)
In between which muscles does the cephalic vein run?
In the groove between deltoid and pectoralis major
Why is the cephalic vein clinically important?
For pacemaker insertion. A pacemaker is inserted just under the skin next to the left cephalic vein and a wire is threaded so that the tip of the wire rests against the tip of the right ventricle or against the SA node.
