MSK 3.2 - Superficial Muscles of the Back Flashcards
Where does the trapezius originate? (3)
- Ligamentum Nuchae (Superior)
- Spinous processes C7-T5 (middle)
- Spinous processes T6-T12 (Inferior)
Where does the trapezius insert? (4)
- Superior fibres = Posterior border of lateral third of clavicle
- Middle fibres = Medial margin of acromion and superior border of posterior part of the scapula spine
- Inferior fibres = Tubercule at apex triangle at medial spine of scapula
Which nerves innervate the trapezius? What type nerve are these?
- Accessory nerve (motor)
also has proprioceptor fibres from C3 and C4
What are the actions of the trapezius? (3)
- Rotation and elevation of scapula when arm is abducted
- Retraction of scapula
- Pulls scapula inferiorly
What is the most common cause of damage to the accessory nerve? What happens as a result of this?
- Damage is latrogenic (due to a medical procedure)
- Loss of trapezius function
Where does the Latissimus Dorsi originate? (4)
- Spinous processes from T6-T12
- Iliac crest
- Thoracolumbar fascia
- Inferior three ribs
Where does the Latissimus Dorsi insert?
Intertubecular groove of the humerus
Which nerve innervates the Latissimus Dorsi?
Thoracodorsal nerve
What are the actions of the Latissimus Dorsi? (3)
- Extension
- Adduction
- Medial rotation
Of upper limb
Describe the shape and size of the Levator Scapulae
- Small
- Strap like
Describe the shape of the trapezius
- Broad
- Flat
- Triangular
What is the origin of levator scapulae?
Transverse processes of C1-C4 vertebrae
Where does levator scapulae insert?
The medial border of the scapula
What is the innervation of levator scapulae?
Dorsal scapular nerve
What is the arterial supply of levator scapulae?
Dorsal scapular artery
What are the actions of levator scapulae?
Elevation of the scapula
What is the origin of rhomboid major?
Spinous processes of T2-T5 vertebrae
Where does rhomboid major insert?
Medial border of the scapula (between the spine and inferior angle)
What is the innervation of rhomboid major?
Dorsal scapular nerve
What is the arterial supply of rhomboid major?
Dorsal scapular artery
What are the actions of rhomboid major?
Retraction and rotation of the scapula
What is the origin of rhomboid minor?
The spinous processes of C7-T1 vertebrae
Where does rhomboid minor insert?
Medial border of the scapula, at the level of the spine
What is the innervation of rhomboid minor?
Dorsal scapula nerve
