The Appendicular: Upper Limb

Question 1

Trapezius

Answer 1

• origin: occipital bone, spinous process of cervical and thoracic vertebrae
• insertion: clavicle and scapula
• action: elevates, retracts, and depresses scapula, extends neck

Question 2

Levator scapulae

Answer 2

• origin: transverse process of upper cervical vertebrae
• insertion: scapula
• action: elevate scapula
• shrugging of shoulders

Question 3

Rhomboid major and minor

Answer 3

• origin: spinous process of thoracic vertebrae
• insertion: medial edge of scapula
• action: retraction of scapula

Question 4

Serratus anterior

Answer 4

• origin: anterior aspect of ribs
• insertion: anterior aspect of scapula
• action: protract scapula (hold it against thoracic cage)

Question 5

Deltoid

Answer 5

• origin: clavicle, spine of scapula
• insertion: humerus (deltoid tuberosity)
• action: abduct, flex and medically rotate, extend and laterally rotate

Question 6

Rotator Cuff: Supraspinatus

Answer 6

• origin: scapula (supraspinous fossa)
• insertion: humerus (greater tubercule/posterior aspect)
• action: abduct arm

Question 7

Rotator Cuff: Infraspinatus

Answer 7

• origin: scapula (infraspinous fossa)
• insertion: humerus (greater tubercle/posterior aspect)
• action: laterally rotate arm

Question 8

Rotator Cuff: Subscapularis

Answer 8

• origin: scapula
• insertion: humerus (lesser tubercule)
• action: medially rotate arm

Question 9

Rotator Cuff: teres major

Answer 9

• origin: scapula
• insertion: humerus (anterior aspect)
• action: extend and medially rotate arm

Question 10

Latissimus Dorsi

Answer 10

• origin: spinous processes of vertebrae
• insertion: humerus
• action: extend, adduct, medially rotate arm
• handcuffs

Question 11

Pectoralis major

Answer 11

• origin: clavicle and sternum
• insertion: humerus
• action: flex, adduct, medially rotate

Question 12

Flexor compartment: biceps brachii

Answer 12

• origin: coracoid process of scapula (short head), supraglenoid tubercle (long head)
• insertion: radius
• action: flex arm, flex and supinate forearm (palms facing up)

Question 13

Flexor compartment: coracobrachialis (deep to short head of biceps brachii)

Answer 13

• origin: coracoid process of scapula
• insertion: humerus
• action: flex, adduct arm

Question 14

Flexor compartment: Brachialis (deep to muscle belly of biceps brachii)

Answer 14

• origin: humerus
• insertion: ulna
• action: flex forearm

Question 15

Extensor compartment : triceps brachii

Answer 15

• origin: humerus and scapula
• insertion: olecranon process of ulna
• action: extend arm

Question 16

Superficial Flexor Compartment: flexor carpi radialis, flexor carpi ulnaris, flexor digitorum superficialis

Answer 16

• origin: medial epicondyle of the humerus
• insertion: varies — lateral side of wrist, medial side of wrist, digits
• action: flex wrist and digits, pronate forearm (palms facing down)

Question 17

Extensor compartment of forearm: Extensor carpi radialis longus and brevis, extensor carpi ulnaris, extensor digitorum

Answer 17

• origin: lateral epicondyle of humerus
• insertion: varies
• action: extend wrist and digits, supinate forearm

Question 18

Hypothenar muscles

Answer 18

• origin: -
• insertion: phalanges of the fifth digit
• action: act on the fifth digit: flexion, extension, abduction, adduction

Question 19

Thenar muscles

Answer 19

• origin: -
• insertion: phalanges of the pollux
• action: act on the thumb: flexion, abduction, adduction, extension, opposition

Question 20

Palmar interossei

Answer 20

• origin: metacarpals
• insertion: proximal phalanges
• action: adduct digits 2-4

Question 21

Dorsal interossei

Answer 21

• origin: metacarpals
• insertion: proximal phalanges
• action: abduct digits 2-4

Question 22

Compartments of the arm

Answer 22

Flexor compartment (anterior): biceps brachii, brachialis, brachial artery and median nerve
Extensor compartment (posterior): triceps brachii

Question 23

Compartments of the forearm

Answer 23

• lateral compartment: brachioradialis, extensor carpi radialis brevis
• superficial flexor compartment: flexor digitorum superficialis
• deep flexor compartment: flexor digitorum profundus
• extensor compartment: extensor carpi ulnaris, extensor digitorum