Muscles of Thoracic Wall - Exam 2

Question 1

pectoralis major origin

Answer 1

clavicular origin - clavicle (medial portion)
sternocostal origin - sternum and costal cartilages
abdominal origin - costal cartilages

Question 2

pec major insertion

Answer 2

humerus (lateral lip of inter-tubercular groove)

Question 3

pec major actions

Answer 3

ADduction of arm, medial rotation, flexion of arm (clavicular), extension of flexed humerus (sternocostal part)

Question 4

pec major innervation

Answer 4

medial and lateral pectoral nerve

Question 5

pec minor origin

Answer 5

ribs 3-5

Question 6

pec minor insertion

Answer 6

coracoid process of scapula

Question 7

pec minor innervation

Answer 7

medial pectoral nerve (pierces through minor towards major)

Question 8

pec minor action

Answer 8

stabilizes scapula

Question 9

serratus anterior origin

Answer 9

ribs 1-9

Question 10

serratus anterior insertion

Answer 10

medial border of scapula

Question 11

serratus anterior innervation

Answer 11

long thoracic nerve

Question 12

serratus anterior action

Answer 12

scapular protraction, holds scapula against thoracic wall (get winging of scap when thoracic nerve is damaged)

Question 13

subclavius origin

Answer 13

rib 1

Question 14

subclavius insertion

Answer 14

clavicle

Question 15

subclavius innervation

Answer 15

subclavian nerve

Question 16

subclavius action

Answer 16

depression of scap, stabilizes sternoclavicular joint