Posterior forearm, Dorsum of hand, Joints of upper limb Session 30

Question 1

what innervates the posterior forearm

Answer 1

radial nerve

Question 2

what r the two layer of muscles in the posterior forearm

Answer 2

superficial and deep

Question 3

what r the 6 superficial muscles in the posterior compartment

Answer 3

brachioradialis
extensor carpi radialis longus and brevis
extensor digitorum
extensor digiti minimi
extensor carpi ulnaris

Question 4

where do the superficial layer of muscle in the posterior compartment attach to

Answer 4

lateral epicondyle of the humerus

Question 5

where is brachioradialis located and where does it insert

Answer 5

boundary between posterior and anterior compartments

inserts onto distal radius

Question 6

action of brachioradialis

Answer 6

weak flexor of elbow joint

Question 7

what r the insertions of the extensor carpi radialis longus and brevis

Answer 7

longus= 2nd metacarpal (index)
brevis= 3rd metacarpal (middle)

Question 8

actions of extensor carpi radialis longus and brevis

Answer 8

extend and abduct wrist

Question 9

where does extensor digitorum insert onto

Answer 9

onto dorsal aspects of all four fingers

Question 10

why is it difficult to fully extend the middle or ring finger independantly

Answer 10

tendons of extensor digitorum r connected by fibrous bands

Question 11

where is the insertion and what is the action of extensor digiti minimi

Answer 11

inserts onto dorsum of pinky

extends little finger

Question 12

what is the insertion and action of extensor carpi ulnaris

Answer 12

5th metacarpal

extends and adducts the wrist

Question 13

what travels under the extensor retinaculum and what is the retinaculums function

Answer 13

all muscle tendons

prevents tendons from bowing when wrist is extended

Question 14

what r the 5 deep muscles of the posterior compartment

Answer 14

supinator
abductor pollicis longus
extensor pollicis brevis
extensor pollicis longus
extensor indicis

Question 15

what is the origin of the deep muscles and what is the exception

Answer 15

forearm bones and interosseous membrane

exception: supinator

Question 16

what is the attachment of supinator and its interaction with the radius

Answer 16

origin from lateral epicondyle of the humerus

wraps around upper part of radialis

Question 17

what three posterior forearm muscles r not extensors

Answer 17

brachioradialis
supinator
abductor pollicis longus

Question 18

what is the action of supinator

Answer 18

supinates forearm

Question 19

action and insertion of abductor pollicis longus

Answer 19

abducts thumb

inserts onto 1st metacarpal

Question 20

what two muscles extend the thumb

Answer 20

extensor pollicis brevis and longus

Question 21

what is the insertion and movements of extensor pollicis brevis

Answer 21

proximal phalanx

extends the metacarpalphalangeal joint

Question 22

what is the insertion and movements of extensor pollicis longus

Answer 22

inserts onto distal phalynx

extends the interphalangeal joint of thumb (only muscle that can do this)

Question 23

what is the insertion and action of extensor indicis

Answer 23

inserts onto dorsum of index finger

independant extension of index finger

Question 24

what is the only intrinsic muscle on the dorsal aspect of the hand (group of muscles)

Answer 24

dorsal interossei

Question 25

where do the veins drain into 1) the hand 2) the forearm

Answer 25

1) into the dorsal venous network on the back of the hand

2) cephalic vein laterally and basilic vein medially

Question 26

how do the tendons of the digits and the extensor hoods interact and what is the purpose of this

Answer 26

tendons of extensor digitorum, indicis and digiti minimi insert onto dorsal aspect of extensor hoods
keeps tendons fixed in midline

Question 27

what is the insertion of lumbricals and interossei onto extensor hoods and what joint do they extend

Answer 27

insert into side of proximal parts of extensor hoods

extension of interphalangeal joints of fingers

Question 28

where/what is the anatomical snuffbox and when can it be seen best

Answer 28

triangle shaped depression between thumb and wrist

seen when thumb is extended as much as possible

Question 29

what r the boundaries of the anatomical snuffbox

Answer 29

medial: tendon of extensor policis longus
lateral: tendons of extensor pollicis brevis and abductor pollicis longus

Question 30

what lies in the floor of the anatomical snuffbox (1)
what arises here (1)
what passes through (1)
what passes over (1)

Answer 30

scaphoid lies in floor
radial artery passes through it
superficial branch of radial nerve passes over it
cephalic vein arises here

Question 31

what is the ulnar artery usually accompanied with (posterior compartment)

Answer 31

deep veins

Question 32

what type of joint is the shoulder joint and what is it formed between

Answer 32

synovial ball and socket

glenoid fossa of scapula and head of humerus

Question 33

what four things increase stability of the shoulder joint

Answer 33

ligaments
glenoid labrum (rim of fibrocartilage that deepens glenoid fossa)
rotator cuff muscles
tendon of long head of biceps (inserts onto supraglenoid tubercle of scapula)

Question 34

what type of joint is the elbow joint

Answer 34

synovial hinge joint

Question 35

what 2 pairs of structures form the elbow joint

Answer 35

trochlea of humerus and trochlear notch of ulnar

capitellum of humerus and radial head

Question 36

what reinforces the elbow joint

Answer 36

ulnar and radial ligaments

Question 37

what type of joint is the radioulnar joint

Answer 37

synovial pivot type joint

Question 38

how does the radius rotate around the ulnar and what movement is this

Answer 38

radial head rotates in the annular ligament

pronation

Question 39

what type of joint is a wrist joint

Answer 39

condyloid synovial joint

Question 40

what structures form the wrist joint

Answer 40

distal radius and scaphoid and lunate

Question 41

what capsule is the wrist joint and what is it reinforced by

Answer 41

joint capsule which is also reinforced by ligaments

Question 42

what type of joints r interphalangeal joints and how r they reinforced

Answer 42

synovial hinge

by ligaments

Question 43

what type of joints r interphalngeal joints

Answer 43

hinge joints

Question 44

what type of joints r metacarophalangeal joints

Answer 44

condyloid joints

Question 45

what type of joint is the first carpometacarpal joint (thumb) and between which bones is it located

Answer 45

saddle joint

between trapezium and 1st metacarpal

Question 46

what structure reinforces the joints of the hand between bones (hint: same as everything else)

Answer 46

ligaments

Question 47

what is the insertion of the tendon of long head of biceps

Answer 47

inserts onto supraglenoid tubercle of scapula