topic 11: 11. The anatomy, innervation and function of the spinohumeral and thoracohumeral muscles

Question 1

SPINOHUMERAL MUSCLES

Answer 1

1.Trapezius
2.Latissimus dorsi
3.Rhomboid minor & major
4.Levator scapulae

origin: spinal & transverse process of vertebrae
insetion: humerus

Question 2

Trapezius: innervation & function

Answer 2

Innervation: Accesory nerve (cranial nerve XI)
Functions: sup.rotation,retraction and elevation/depression of scapula

Question 3

Lattisimus dorsi

Answer 3

innervation: thoracodorsal nerve
function: retroflexion(bent backwards), adduction, med. rotation of arm @ glenohumeral joint

Question 4

Rhomboid minor & major

Answer 4

nerve: dorsal scapular
function: stabilization, internal rotation, retraction & elevation of scapula

Question 5

Levator scapulae

Answer 5

n: dorsal scapular & cervical spinal n
function: flexes head & neck and elevation of shoulder

Question 6

THORACOHUMERAL MUSCLES

Answer 6

1.Pectoralis major
2.Pectoralis minor
3.Serratus anterior
4.Subclavius

o: thorax & ribs
i: humerus

Question 7

pectoralis major

Answer 7

has 3 parts : clavicular,abdominal & sternal parts

nerve : medial & lateral pectoral nerves
functions: adduction & internal roation of arm @ shoulder joint/ clavicular part helps flex extended arm @ 90°

Question 8

pectoralis minor

Answer 8

nerve: med. & lat. pectoral nerves
functions:stabilization, depression, abduction , internal and downward rotation of the scapula.
(aids in respiration)

Question 9

serratus anterior

Answer 9

fan-shaped muscle
n: long thoracic nerve
f:protaction of shoulder blades, elevation of ribs & lowers arm from raised position

Question 10

subclavius

Answer 10

n: nerve to subclavius
f: achores & depresses clavicle, elevates 1st rib