Muscles (shoulder) Flashcards
Where does the pec major muscle insert?
Lateral of the bicipital groove
Where does the pec major originate from?
The clavicle
Costal cartilages
Sternum
What is the action of the pec major?
Medially rotate the arm and adduction
What is the innervation of the pec major?
Medial and lateral pectoral nerve
Where does the pec minor originate from?
Ribs 3-5
Where does the pec minor insert into?
The coracoid process of the sternum
What are the actions of the pec minor?
Pull the scapula forwards and downwards
Pull the scapula against the thoracic wall to stabilise it
What is the innervation of the pec minor?
Medial pectoral nerve
What is the origin of the serratus anterior?
Strips from ribs 1-8
What is the insertion of the serratus anterior?
Medial border of the costal surface of the scapula
What is the action of the serratus anterior?
To hold the scapula against the ribs and to rotate the scapula
What is the innervation of the serratus anterior?
Long thoratic nerve
What happens if the long thoratic nerve is damaged?
Seratus anteior is paralysed and the medial border of the scapula is no longer held against the ribs - winging of he scapula
What is the origin of the trapezius?
Skull
Spinous processes of C7-T12
What is the insertion of the trapezius?
Spine of scapula
Acromion of scapula
Clavicle
What is the action of the trapezius?
Upper fibres - lift and rotate the scapula during abduction
Middle - retract scapula
Lower - pull scapula inferiorly
What is the innervation of the trapezius?
C3 and C4
What are the superficial back muscles?
Trapezius and Lat dorsi
What is the main origin for the lat dorsi?
T6-T12
What is the insertion of the lat dorsi?
Converge into tendon into the middle of the bicipital groove
What is the action of the lat dorsi?
Medial rotation and adduction of the arm
What is the innervation of the lat dorsi?
C6-C8
What does the doral scapula nerve innervated?
- Levitator scapulae
- Rhomboid major
- Rhomboid minor
What is the insertion of the levator scapulae?
Medial border of scapula (above the spine)
What is the action of the lavator scapulae?
Elevate the scapula
What is the insertion of the rhomboid minor?
Medial border of the scapula (at the level of the spine)
What is the action of the rhomboid minor?
Retract and rotate scapula
What is the insertion of the rhomboid major?
Medial border of the scapula (below the spine)
What is the action of the rhomboid major?
Retract and rotate scapula
Where do the rhomboid major and minor lie in relation to each other?
Rhomboid minor is superior to rhomboid major
What does the axillary nerve innervate?
The deltoid and teres minor
What does the suprascapular nerve innervate?
Supraspinatous and infraspinatous muscles
What innervates the teres major?
Lower subscpular nerve
What innervates he subscapularis?
Upper and lower subscapular nerves
What is the origin of the deltoid?
Clavicle
Spine of scapula
Acromion of scapula
What is the insertion of the deltoid?
Deltoid tuberocity on the lateral surface of the humerus
What is the action of the deltoid?
Anterior - flexion and medial rotation
Posterior - extension and lateral rotation
Middle - Major abductor of the arm
What is the trapezium and the deltoid divided into?
3 areas of muscle fibres, all with different functions
What is the insertion of the teres major muscle?
Medial border of the inter-tubercular groove
What is the action of the teres major?
Medially rotate and adduct the arm
What is the action of the subscapularis?
Medially rotate the arm
What is the action of the teres minor and infraspinatous?
Laterally rotate the arm
What is the function of the supraspinatous?
Abduct the arm the first 15º
Where do the rotator cuff muscles insert?
APART FROM WHICH ROTATOR CUFF??????
Where does this insert?
Onto the greater tubercle of the humerus
APART FROM:
The subscapularis - inserts onto the LESSER tubercle
What is the origin of the teres major?
Inferior angle of the scapula (posteriorly)
What is the origin of the teres minor?
Posterior surface of the scapula (adjacent to lateral border)
