Forearm and Hand

Question 1

carpi

Answer 1

wrist

Question 2

pollicis

Answer 2

thumb

Question 3

digitorum

Answer 3

digits 2-5

Question 4

indicis

Answer 4

digit 2

Question 5

digiti minimi

Answer 5

digit 5

Question 6

extrinsic hand muscle have muscle bellies located where?

Answer 6

in the forearm

Question 7

extrinsic muscle provide what to movements?

Answer 7

strength

Question 8

intrinsic hand muscles have muscle bellies located where?

Answer 8

in the hand

Question 9

intrinsic muscle provide what to movements?

Answer 9

precision

Question 10

the median nerve innervates which muscles of layer one of the flexor forearm? what are their actions?

Answer 10

pronator teres (pronates)
flexor carpi radialis (abducts wrist) radial deviation 
palmaris longus (flexes)

Question 11

the ulnar nerve innervates what muscle of layer one? what movement does it perform?

Answer 11

flexor carpi ulnaris? flexion and adducts the wrist

Question 12

how many muscles are in layer 2 of the flexor forearm? what are its actions? what digits are covered? what nerve innervates it?

Answer 12

1. flexor digitorum superficialis

flex the elbow, wrist, cmc, mcp, pip joints

median nerve

Question 13

what muscles make up layer 3 of the flexor forearm?

Answer 13

flexor pollicis longus

flexor digitorum profundus

Question 14

what innervates the flexor pollicis longus?

Answer 14

median nerve

Question 15

what innervates flexor digitorum profundus?

Answer 15

digits 2&3 median nerve

digits 4&5 ulnar nerve

Question 16

what muscle is in layer 4 of the flexor forearm? where does pronation occur? what nerve innervates it?

Answer 16

pronator quadratus
pronation occurs at radioulnar joints

innervated by median nerve

Question 17

what forms the roof of the carpal tunnel

Answer 17

flexor retinaculum

Question 18

what structures travel through the carpal tunnel?

Answer 18

flexor digitorum tendons (8)
(flexor digitorum superficialis and profundus)
flexor pollicis longus (1)
median nerve (1)

Question 19

inflammation of synovial sheath cause median nerve entrapment- this is called?

Answer 19

carpal tunnel syndrome

Question 20

what are the three muscle compartments of the extensor forearm? what nerve are they innervated by? the tendons traveling into the hand are held against bone by what?

Answer 20

lateral, medial , deep

all innervated by radial nerve

tendons traveling into hand are held against bone by extensor retinaculum

Question 21

what are the three muscles in the lateral group of the extensor forearm? what movements do they do?

Answer 21

brachioradialis (supination and pronation)

extensor carpi radialis longus (abduct wrist)

extensor carpi radialis brevis (abduct wrist)

*all flex the elbow
extensor carpi muscles cross and extend wrist

Question 22

why do the lateral muscles of the extensor forearm flex the the elbow instead of extend?

Answer 22

they cross anterior to the transverse axis of the elbow

Question 23

brachioradialis muscle is the handshake muscle, why?

Answer 23

it supinates and pronates

pronates a supinated forearm, supinates a pronated forearm

Question 24

what are the medial muscles of the extensor forearm? what is their action? what happens when tendons reach the hand?

Answer 24

extensor carpi ulnaris- extends the elbow and the wrist (aDducts wrist)

extensor digitorum

extensor digiti minimi

*tendons from extensor hoods/ expansions

Question 25

can the extensor digitorum and extensor digiti minimi fully extend pip and dip joints?

Answer 25

No -they need help from the intrinsic hand muscles

Question 26

what are the deep muscles of the extensor forearm?

Answer 26

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

Question 27

what movement do the abductor pollicis longus, extensor pollicis brevis and extensor pollicis longus?

Answer 27

extensor pollicis longus travels posterior to the transverse axis so it extends the wrist abductor pollicis longus, extensor pollicis brevis cross the wrist anterior to the transverse axis so they flex the wrist *abduct the wrist

Question 28

what makes up the anatomical snuffbox?

Answer 28

abductor pollicis longus extensor pollicis brevis extensor pollicis longus

Question 29

what artery travels through the snuffbox?

Answer 29

radial artery

Question 30

the dorsal hand has no? what does it have instead?

Answer 30

intrinsic muscles in the dorsum of the hand extensor retinaculum, tendons, hood

Question 31

what crosses CMC and MCP joints of digit 1 and is innervated by the median nerve?

Answer 31

Thenar eminence

Question 32

what muscles are in the thenar eminence?

Answer 32

Flexor pollicis brevis abductor pollicis brevis opponens pollicis

Question 33

what crosses the CMC and MCP joints of digit 5 and is innervated by the ulnar nerve

Answer 33

Hypothenar eminence

Question 34

what muscles are in the Hypothenar eminence?

Answer 34

abductor digiti minimi flexor digiti minimi opponens digiti minimi

Question 35

what is a muscle that is not a part of the Thenar eminence but it also moves the thumb? what is it innervated by?

Answer 35

Adductor pollicis brevis the ulnar nerve

Question 36

what do lumbricals originate from? what are they innervated by?

Answer 36

originate from tendons of flexor digitorum profundus lumbricals 1&2- median nerve lumbricals 3&4- ulnar nerve

Question 37

what are the deepest muscles in the palmar hand?

Answer 37

Dorsal and palmar interossei

Question 38

the dorsal and palmar interossei cross what joints? what is the midline? What nerve innervates it?

Answer 38

Cross MCP joints digit 3 is midline and innervated by ulnar nerve

Question 39

Dorsal interossei perform what action

Answer 39

abduct

Question 40

the palmar interossei

Answer 40

adduct

Question 41

lumbricals and interossei have commonalities what are they?

Answer 41

both lumbricals and interossei insert on extensor hood cross anterior to MCP joints, flex MCP joints pulls tense extensor hood.

Question 42

the only way to fully extend PIP and DIPs is

Answer 42

the lumbricals and interossei muscle tense extensor hood. Since the extensor hood is posterior to PIP and DIP joints, they extend pip and dip joints

Question 43

the ulnar nerve travels through which canal?

Answer 43

Guyon's canal

Question 44

damage to the ulnar nerve can result in?

Answer 44

sensory loss to digits 4&5 | "claw hand"

Question 45

Damage to the ulnar nerve can cause claw hand. How?

Answer 45

loss of all interossei and two lumbricals. | digits 4&5- hyperextended MCP, flexed PIP and DIP

Question 46

what branches off of the ulnar artery?

Answer 46

common interosseous artery

Question 47

which artery is more superficial? Radial or ulnar?

Answer 47

radial

Question 48

in the hand the ulnar becomes? what branches from it

Answer 48

the superficial palmar arch | common digital artery which birfucates into the proper digital arteries `

Question 49

the radial artery wraps around the thumb and travels through the snuffbox? what artery does it become?

Answer 49

deep palmar arch

Question 50

true or false: there is an anastomoses between arches and arteries in the hand?

Answer 50

true

Question 51

damage to the hypothenar can cause? What helps prevent full occlusion?

Answer 51

hypothenar hammer injury- (damaged and occluded ulnar artery) the radial artery and anastomosis prevent full occlusion.

Question 52

When abducting the arm fully through 180°, how much of the elevation is due to movement of the glenohumeral (shoulder) joint, and how much is due to rotation of the scapula?

Answer 52

Abduction of the arm is actually a fairly complex process. During the first 30° of abduction, only the glenohumeral joint is in motion, caused first by the supraspinatus primarily (0°-15°) and then by the deltoid. From about 30° to 120°, both the glenohumeral joint and the scapula are moving such that for every 3° of abduction, 2° are contributed by glenohumeral movement and 1° by scapular rotation. From 120° to 180°, abduction results exclusively from rotation of the scapula (the greater tubercle of the humerus bumps against the acromion at about 120°).