Extrinsic Muscles

Question 1

Hypaxial muscle

Answer 1

All muscles except intrinsic muscles

Question 2

Origin of Trapezius Muscle

Answer 2

• 1/3 of superior nuchal line
• external occipital protuberance
  -ligamentum nuchae
• C7-T12

Question 3

Insertion of the descending fibers of Trapezius

Answer 3

1/3 of clavicle

Question 4

Insertion of the middle fibers of Trapezius

Answer 4

Spine and acromion process of scapula

Question 5

Insertion of the ascending fibers of Trapezius

Answer 5

Base of spine of scapula

Question 6

Innervation of Trapezius

Answer 6

Subtrapezial plexus:
- Motor: CNXI accessory nerve
- Sensory: C3-C4 ventral rami

Question 7

Blood Supply for Trapezius

Answer 7

Descending fibers: occipital artery
Middle fibers: transverse cervical artery
Ascending fibers: dorsal scapula artery

Question 8

Actions of Trapezius

Answer 8

• Elevate the shoulders: Shrugging
• depress scapula
• elevate scapula
• bilateral: extends head and neck
• unilateral: ear to shoulder (ipsilateral)

Question 9

Origin of Latissimus Dorsi

Answer 9

• thoracolumbar fascia (spinous process of C7-L5 + posterior iliac crest)
• bone (iliac crest lateral to erector spinae + lower 3-4 ribs)

Question 10

Insertion of Latissimus Dorsi

Answer 10

Floor of bicipital groove

Question 11

Innervation of Latissimus Dorsi

Answer 11

Thoracodorsal nerve fibers (C6-C8 ventral rami)

Question 12

Blood supply of Latissimus Dorsi

Answer 12

Thoracodorsal artery

Question 13

Actions of Latissimus Dorsi

Answer 13

• extension of arm
• adduction of arm
• medial rotation of arm

Question 14

Origin of Levator scapulae

Answer 14

T.P of C1-C4

Question 15

Insertion of Levator scapulae

Answer 15

Medial border of scapula from superior angle to spine of scapula

Question 16

Innervation of Levator Scapulae

Answer 16

C3-C4 ventral rami and dorsal scapular nerve C5

Question 17

Blood supply of Levator Scapulae

Answer 17

Dorsal scapular artery

Question 18

Actions of Levator Scapulae

Answer 18

• Elevates superior angle of scapula
• Inferiorly rotates glenoid fossa

Question 19

Origin of Rhomboid Minor

Answer 19

• Lower portion of ligamentum nuchae
• S.P. of C7-T1

Question 20

Insertion of Rhomboid Minor

Answer 20

Medial border of scapula at base of spine

Question 21

Actions of Rhomboid Minor

Answer 21

• Inferiorly rotates glenoid fossa
• Retracts scapula

Question 22

Innervation of Rhomboid Minor

Answer 22

Dorsal scapular nerve (C4/C5)

Question 23

Blood Supply of Rhomboid Minor

Answer 23

Dorsal Scapular a.

Question 24

Origin of Rhomboid Major

Answer 24

S.P of T2-T5

Question 25

Insertion of Rhomboid Major

Answer 25

Medial border of scapula from base of spine to inferior angle

Question 26

Innervation of Rhomboid Major

Answer 26

Dorsal scapular n (C4/C5)

Question 27

Blood Supply of Rhomboid Major

Answer 27

Dorsal scapular A.

Question 28

Actions of Rhomboid major

Answer 28

- Retract scapula - Inferiorly rotates the glenoid fossa

Question 29

Origin of Serratus Anterior

Answer 29

Ribs 1-8

Question 30

Insertion of Serratus Anterior

Answer 30

Anterior surface of medial border on scapula

Question 31

Actions of Serratus Anterior

Answer 31

- protraction of scapula - elevation and upwards rotation of scapula w/ trapezius

Question 32

Origin of Serratus Posterior Superior

Answer 32

- S.P of C7-T2/3 - Ligamentum Nuchae

Question 33

Insertion of Posterior Serratus Superior

Answer 33

Ribs 2-5 lateral to angle

Question 34

Action of Serratus Posterior Superior

Answer 34

Lift ribs during inhalation

Question 35

Innervation of Serratus Posterior Superior

Answer 35

First 4 intercostal nerves (Ventral rami of T1-T4)

Question 36

Blood Supply of Serratus Posterior Superior

Answer 36

-Highest intercostal artery - Posterior intercostal artery

Question 37

Origin of Serratus posterior inferior

Answer 37

Spinous processes of T11-L2

Question 38

Insertion of Serratus posterior inferior

Answer 38

Lower 4 ribs lateral to angle

Question 39

Action of Serratus Posterior Inferior

Answer 39

Depress lower ribs during inhalation

Question 40

Blood supply of Serratus posterior inferior

Answer 40

Posterior intercostal a.a