Extensor Compartment of Upper Limb and Upper Back

Question 1

Origin of long head of triceps brachii

Answer 1

Infraglenoid tubercle

Question 2

Origin of lateral head of triceps brachii

Answer 2

Humerus, superior to the radial groove

Question 3

Origin of medial head of triceps brachii

Answer 3

Humerus, inferior to radial groove

Question 4

Attachment of triceps brachii

Answer 4

The heads converge onto one tendon and insert into the olecranon of the ulna

Question 5

Function of triceps brachii

Answer 5

Extension of the arm at the elbow

Question 6

Innervation of triceps brachii

Answer 6

Radial nerve

Question 7

How many muscles are in the superficial layer of the posterior forearm

Answer 7

7

Question 8

Origin and attachments of brachioradialis

Answer 8

Originates from the lateral supracondylar ridge of humerus

Attaches to the distal end of the humerus

Question 9

Actions of brachioradialis

Answer 9

Flexes at the elbow

Question 10

Innervation of brachioradialis

Answer 10

Radial nerve

Question 11

Origin and attachments of extensor carpi radialis longus

Answer 11

Originates from the supracondylar ridge

Their tendons attach to metacarpal bones II and III

Question 12

Origin and attachments of extensor carpi radialis brevis

Answer 12

Originates from the lateral epicondyle

Their tendons attach to metacarpal bones II and III

Question 13

Action of extensor carpi radialis longus and brevis

Answer 13

Extends and abducts the wrist

Question 14

Innervation of extensor carpi radialis longus and brevis

Answer 14

Radial nerve

Question 15

Origin and attachment of extensor digitorum

Answer 15

Originates from lateral epicondyle

Splits into four and inserts into the extensor hood of each finger

Question 16

Action of extensor digitorum

Answer 16

Extends four fingers at metacarpophalangeal joint and interphalangeal joints

Question 17

Innervation of extensor digitorum

Answer 17

Radial nerve (deep branch)

Question 18

Origin and attachment of extensor digiti minimi

Answer 18

Originates from lateral epicondyle

Attaches with the extensor digitorum tendon into the extensor hood of the little finger

Question 19

Actions of extensor digiti minimi

Answer 19

Extends the little finger

Contributes to extension at the wrist

Question 20

Innervation of extensor digiti minimi

Answer 20

Radial nerve (deep branch)

Question 21

Origin and attachment of extensor carpi ulnaris

Answer 21

Originates from the lateral epicondyle

Attaches to base of metacarpal V

Question 22

Action of extensor carpi ulnaris

Answer 22

Extension and adduction of wrist

Question 23

Innervation of extensor carpi ulnaris

Answer 23

Radial nerve (deep branch)

Question 24

Origin and attachment of anconeus

Answer 24

Originates from lateral epicondyle

Attaches to olecranon

Question 25

Action of anconeus

Answer 25

Extends and stabilises elbow joint | Abducts the ulna during pronation of the arm

Question 26

Innervation of anconeus

Answer 26

Radial nerve

Question 27

How many muscles are in the deep compartment of the posterior forearm

Answer 27

5

Question 28

With the exception of the supinator, the deep muscles in the posterior forearm act on ...

Answer 28

Thumb and index finger

Question 29

The deep branch of the radial nerve passes between the two heads of which muscle

Answer 29

Supinator

Question 30

Origin and attachment of the supinator

Answer 30

One head originates from lateral epicondyle and the other from the posterior surface of the ulna Attaches to the posterior surface of the radius

Question 31

Actions of supinator

Answer 31

Supinates the forearm

Question 32

Innervation of supinator

Answer 32

Radial nerve

Question 33

Origin and attachment of abductor pollicis longus

Answer 33

Originates from the interosseous and adjacent surfaces of the radius and ulna Attaches to the lateral side of the base of metacarpal I

Question 34

Action of abductor pollicis longus

Answer 34

Abducts the thumb

Question 35

Innervation of abductor pollicis longus

Answer 35

Radial nerve (posterior interosseous branch)

Question 36

Origin and attachment of extensor pollicis brevis

Answer 36

Originates from posterior surface of the radius and interosseous membrane Attaches to proximal phalanx of the thumb

Question 37

Action of extensor pollicis brevis

Answer 37

Extends at metacarpophalangeal joints and carpometacarpal joints of the thumb

Question 38

Innervation of extensor pollicis brevis

Answer 38

Radial nerve (posterior interosseous branch)

Question 39

Origin and attachments of extensor pollicis longus

Answer 39

Originates from posterior surface of ulna and interosseous membrane Attaches to the distal phalanx of the thumb

Question 40

Action of extensor pollicis longus

Answer 40

Extends all joints of the thumb

Question 41

Innervation of extensor pollicis longus

Answer 41

Radial nerve (posterior interosseous branch)

Question 42

Origin and attachments of extensor indicis proprius

Answer 42

Originates from the posterior surface of the ulna and interosseous membrane Attaches to the extensor hood of the index finger

Question 43

Action of extensor indicis proprius

Answer 43

Extends the index finger

Question 44

Innervation of extensor indicis proprius

Answer 44

Radial nerve (posterior interosseous branch)

Question 45

... is a thick strip of connective tissue which forms the roof of the carpal tunnel

Answer 45

Flexor retinaculum

Question 46

Attachments of flexor retinaculum

Answer 46

Medially- Pisiform and hook of hamate | Laterally- Trapezium and scaphoid

Question 47

... is a thickening of the fascia on the dorsum of the hand keeps the extensor tendons in position

Answer 47

Extensor retinaculum

Question 48

The radial and ulnar arteries are formed by bifurcation of the ... within the cubital fossa

Answer 48

Brachial artery

Question 49

Radial artery supplies the ... aspect of the forearm

Answer 49

Posterolateral

Question 50

Ulnar artery supplies the ... aspect of the forearm

Answer 50

Anteromedial

Question 51

Radial and ulnar arteries anastomose in the hand forming two arches which are ...

Answer 51

Superificial palmar arch | Deep palmar arch