Muscles of the back Flashcards
Trapezius origin
Medial third of the superior nuchal line, external occipital protuberance, ligamentum nuchae, C1-T12 spinous processes
Trapezius insertion
Spine of scapula, acromion, lateral third of the clavicle
Trapezius action
Elevates, retracts, superiorly rotates the scapula
Trapezius innervation
Spinal accessory nerve (CN XI) (motor), C3-C4 ventral rami (sensory)
Trapezius blood supply
Transverse cervical artery
Latissimus dorsi origin
T7-L5 spinous processes, thoracolumbar fascia, dorsal sacrum, iliac crest
Latissimus dorsi insertion
Floor of inter tubercular sulcus of humerus
Latissimus dorsi actions
Extends, adducts, and medially rotates the humerus
Depresses, retracts, and inferiorly rotates the scapula
Latissimus dorsi innervation
Thoracodorsal nerve
Latissimus dorsi blood supply
Thoracodorsal artery
Rhomboid major origin
T2-T5 spinous processes
Rhomboid major insertion
Medial border of the scapula
Rhomboid major actions
Retracts, elevates, and inferiorly rotates the scapula
Rhomboid major innervation
Dorsal scapular nerve
Rhomboid major blood supply
Dorsal scapular artery
Rhomboid minor origin
C7-T1 spinous processes
Rhomboid minor insertion
Medial border of the scapula
Rhomboid minor actions
Retractes, elevates, and inferiorly rotates the scapula
Rhomboid minor innervation
Dorsal scapular nerve
Rhomboid minor blood supply
Dorsal scapular artery
Levator scapulae origin
C1-C4 transverse processes
Levator scapulae insertion
Superior angle of the scapula
Levator scapulae actions
Elevates and inferiorly rotates the scapula, assists neck extension
Levator scapulae innervation
Dorsal scapular nerve
Levator scapular blood supply
Dorsal scapular artery
What are the superficial (extrinsic) muscles of the back?
Trapezius, Latissimus dorsi, Rhomboid major, Rhomboid minor, Levator scapulae
What are the intermediate muscles of the back?
Serratus posterior superior, Serratus posterior inferior
Serratus posterior superior origin
C7-T3 spinous processes
Serratus posterior superior insertion
Superior border of ribs 2-5
Serratus posterior superior actions
Elevates (weakly) ribs 2-5 (accessory muscle if respiration)