muscle anatomy

Question 1

Levator scapula origin

Answer 1

posterior tubercle of transverse process of C1-4

Question 2

Levator scapula insertion

Answer 2

vertebral margin of scap. between the superior angle and root of scap spine

Question 3

Levator scapula action

Answer 3

• elevates and rotates scapula,
• extends neck with trapezius,
• lateral flexion of neck

Question 4

levator scapula innervation

Answer 4

cervical nerve (C3-C4) and dorsal scapular nerve (C5)

Question 5

Trapezius origin

Answer 5

medial third of superior nuchal line, EOP, nuchal ligament, spices process of C7-T12

Question 6

Trapezius insertion

Answer 6

lateral third of clavicle, acromion, and scap spine

Question 7

Trapezius action

Answer 7

• elevates, retracts, and rotates scapula
• superior fibers elevate, middle retract, inferior depress scapula
• superior and inferior act together for superior rotation of scapula

Question 8

Trapezius innervation

Answer 8

accessory nerve CN XI(motor), cervical nerves C3 and C4 (pain and proprioception

Question 9

sternocleidomastoid origin

Answer 9

manubrium, medial clavicle

Question 10

sternocleidomastoid insertion

Answer 10

mastoid process, superior nuchal line

Question 11

sternocleidomastoid action

Answer 11

• lateral flexion off neck to same side,
• rotates head to opposite side
• bilaterally flexes neck , draws head ventrally and elevates chin”

Question 12

sternocleidomastoid innervation

Answer 12

accessory nerume CN XI

Question 13

pectoralis major origin

Answer 13

clavicular head - anterior surface of medial half of clavicle
sternocostal head- anterior surge of serum, superior six costal cartilages, aponeurosis of external oblique muscle

Question 14

pectoralis major insertion

Answer 14

lateral lip of intertubercular groove of humerus

Question 15

pectoralis major action

Answer 15

• adducts and medially rotates humerus,
• draws scapula anteriorly and inferiorly
• alone clavicular head flexes humerus and sternocostal head extends it

Question 16

pectoralis major innervation

Answer 16

lateral and medical pectoral nerves, clavicular head C5 and C6, sternal head C7, C8, T1

Question 17

deltoid origin

Answer 17

lateral third of clavicle, acromion, scapular spine

Question 18

deltoid insertion

Answer 18

deltoid tuberosity of humerus

Question 19

deltoid action

Answer 19

• anterior fibers flex and medially rotate arm
• middle abducts arm
• posterior extend and laterally rotate arm

Question 20

deltoid innervation

Answer 20

axillary nerve C5 and C6