Trunk - Actions

Question 1

pectoantebrachialis

Answer 1

adduction of arm

Question 2

pectoralis major

Answer 2

flexes and extends humerus

Question 3

pec. minor

Answer 3

stabilizes scapula, raises ribs in inspiration

Question 4

external oblique

Answer 4

contralateral rotation of torso

Question 5

clavotrap

Answer 5

flexes forearm, turns head & extends humerus forward

Question 6

acromiotrap

Answer 6

draws scapula medially & holds scapulae together

Question 7

spinotrap

Answer 7

draws scapula dorsally & posteriorally

Question 8

latissimus dorsi

Answer 8

pulls humerus caudodorsally

Question 9

levator scapulae ventralis

Answer 9

draws scapula cranially

Question 10

acromiodeltoid

Answer 10

extends & rotates humerus

Question 11

spinodeltoid

Answer 11

extends & rotates humerus

Question 12

clavodeltoid

Answer 12

flexes forearm, turns head & extends humerus forward

Question 13

teres major

Answer 13

adduction of humerus

Question 14

subscapularis

Answer 14

medial rotation of humerus

Question 15

xiphihumeralis

Answer 15

Adducts forelimb

Question 16

internal oblique

Answer 16

compresses abdomen, rotation of vertebral column

Question 17

transversus abdominis

Answer 17

compresses abdomenal compartment

Question 18

rectus abdominis

Answer 18

flexion of lumbar spine

Question 19

errector spinae

Answer 19

extends vertebral column

Question 20

scalenus

Answer 20

elevation of 1st and 2nd ribs

Question 21

external intercostals

Answer 21

expands thorax during inhalation

Question 22

rhomboideus major (smaller); rhomboideus minor (larger-behind scapula)

Answer 22

draws vertebral border of scapula medially & dorsally

Question 23

rhomboideus capitis

Answer 23

draws dorsal border of scapula cranially (forward)

Question 24

supraspinatus

Answer 24

extends arm (draws humerus anteriorly)

Question 25

infraspinatus

Answer 25

flexes & rotates humerus laterally (outward)

Question 26

splenius

Answer 26

extend, rotate, and laterally flex head