Muscles of the Shoulder Complex Flashcards
What elevates the scapula?
Levator Scapulae Rhomboids
What depresses the scapula?
Latisimus Dorsi
What abducts the scapula?
Serratus Anterior
What abducts the shoulder?
Middle Deltoid
What upwardly rotates the scapula?
Serratus Anterior Upper and Lower Trapezius
Downward Rotation of Scapula?
Rhomboids Levator Scapulae
What extends the shoulder?
Posterior Deltoid Latissimus Dorsi
What flexes the Shoulder?
Anterior Deltoid
What adducts the Scapula?
Middle Trapezius
What adducts the Shoulder?
Clavicular head of pec major Latissimus Dorsi
CN XI 3rd and 4th Cervical Nerves
Innervation of the Trapezius
Upper: External occipital protuberance Middle: Spinous processes of TV 1-6 Lower: Spinous Processes of TV 7-12
Proximal Attachment of Trapezius
Upper: Lateral third of clavicle Middle: Acromion and crest of scapular spine Lower: Tubercle of scapular spine
Distal Attachment of Trapezius
Dorsal Scapular Artery (3)
Blood Supply of Trapezius, Levator Scapulae, Rhomboids
Thoracodorsal Nerve (C6-8) L
Innervation of Latissimus Dorsi
Spines of TV 7-12 Lumbar and sacral vertebrae
Posterior iliac crest Ribs 9-12
Proximal Attachment of Lat Dorsi
Floor of intertubercular (Bicipital) groove
Distal Attachment of Lat
Extends, adducts and rotates the humerus
Action of Lat
Thoracodorsal artery
Branch of the subscapular artery
Blood Supply of Lat
Cervical Nerves C3-5 Dorsal Scapular Nerve C5
Innervation of Levator Scapulae
Transverse processes of CV 1-4
Proximal Attachment of Levator Scapulae
Medial border of scapula at level of and above the spine
Distal Attachment of Levator Scapulae
- Elevates the scapula at the superior (medial) angle - Assists in the downward rotation of the scapula
Action of Levator Scapulae
Dorsal Scapular Nerve (C5) R
Innervation of Rhomboids
Spines of TV 2-4
Proximal Attachment of Rhomboid Major
Spines of CV 7 and TV 1
Proximal Attachment of Rhomboid Minor
Medial border of scapula from level of the spine inferiorly to the inferior angle
Distal Attachment of Rhomboids
- Adducts scapula - Rotates glenoid fossa downward - Fixes scapula to thoracic wall
Action of Rhomboids
Junction of first rib and costal cartilage 1
Proximal Attachment of Subclavius
Inferior surface of middle third of clavicle
Distal Attachment of Subclavius
Anchors and depresses clavicle
Action of Subclavius
Nerve to subclavius (C5, 6)
Innervation of Subclavius
- Lateral and medial pectoral nerves
Innervation Pectoralis Major
- Anterior surface of the medial half of the clavicle - Anterior surface of the manubrium and body of the sternum - Costal cartilages 2-6 - Aponeurosis of the external oblique
Proximal Attachment of Pec Major
Lateral lip of the bicipital groove/crest of greater tubercle
Distal Attachment of Pec Major
- Adducts and medially rotates arm (humerus) - Flexes arm (clavicular head) - Extends arm (sternal head) from flexed position - Draws scapula anteriorly and inferiorly
Action of the Pec Major
Medial Pectoral Nerve (C8,T1)
Innervation of Pec Minor
Ribs 3-5 near costal cartilage
Proximal Attachment of Pec Minor
Coracoid process
Distal Attachment of Pec Minor
Draws scapula inferiorly and anteriorly against thoracic wall (stabilizes scapula)
Action of Pec Minor
Long thoracic nerve (C5-7)
Innervation of Serratus Anterior
External surface of lateral parts of ribs 1-8
Proximal Attachment of Serratus Anterior
Anterior surface of medial border of scapula
Distal attachment of Serratus Anterior
- Protracts Scapula - Fixes Scapula to Thoracic Wall - Rotates Scapula
Action of Serratus Anterior
Lateral thoracic artery
Blood Supply of Serratus Anterior
Axillary Nerve (2)
Innervation of Deltoid
Innervation of Teres Minor
- Lateral 1/3 of clavicle - Acromion and spine of scapula
Proximal Attachment of Deltoid
Deltoid tuberosity of humerus
Distal Attachment of Deltoid
Flexes, medially rotates, abducts extends and laterally rotates humerus
Action of Deltoid
Thoracocromial artery
Blood Supply of Deltoid
Lower Subscapular nerve (C5, 6)
Innervation of Teres Major
Posterior surface of inferior angle of scapula
Proximal Attachment of Teres Major
Medial lip of bicipital groove of humerus
Distal Attachment of Teres Major
Adducts and medially rotates the humerus
Action of Teres Major
Circumflex scapular artery
Blood Supply of Teres Major, Teres Minor
Supraspinatus Infraspinatus Teres Minor Subscapularis
What are the 4 rotator cuff muscles?
Suprascapular Nerve (2)
Innervation of Supraspinatus
Infraspinatus
Supraspinous fossa of scapula
Proximal Attachment of Supraspinatus
Superior facet of greater tubercle of humerus
Distal Attachment of Supraspinatus
- Works with deltoid in abduction of humerus - Acts with other RC muscles in stabilizing shoulder joint
Action of Supraspinatus
Suprascapular Artery (3)
Blood Supply of Supraspinatus, Infraspinatus, Subscapularis
Infraspinous Fossa of Scapula
Proximal Attachment of Infraspinatus
Middle facet of greater tubercle of humerus
Distal Attachment of Infraspinatus
- Laterally rotates humerus - Helps hold humeral head in place
Action of Infraspinatus
Middle part of lateral border of scapula
Proximal Attachment of Teres Minor
Inferior facet of greater tubercle of humerus
Distal Attachment of Teres Minor
- Laterally rotates humerus - Helps hold humeral head in place
Action of Teres Minor
Upper and Lower subscapular nerves (C5, 6, 7)
Innervation of Subscapularis
Subscapular fossa of scapula (anterior surface)
Proximal Attachment of Subscapularis
Lesser tubercle of humerus
Distal Attachment of Subscapularis
- Medially rotates and adducts humerus - Helps hold humeral head in place
Action of Subscapularis