Anat Limb 4

Front 1

Movements of the Hand

Back 1

• Flexion is bending
• Extension is straightening
• Abduction brings the fingers apart
• Adduction brings the fingers together

Front 2

Movements of the Thumb

Back 2

• Flexion is bending the thumb towards the palm
• Extension is away from the palm
*Flexion and extension is in the coronal plane (parallel to the
plane of the palm)
• Abduction is raising the thumb away from the palm
• Adduction is bringing the thumb to the palm
• Opposition is bringing the pad of the thumb in contact with the pad of a finger
• Reposition is the opposite of opposition

Front 3

• Eight carpal bones

Back 3

pisiform, triquetrum, hamate, capitate, trapezoid, trapezium, lunate and scaphoid

Front 4

o Medial side of the bony palm

Back 4

pisiform bone and hook of hamate

Front 5

o Lateral side of wrist of the bony palm

Back 5

tubercle of the scaphoid and the tubercle of the trapezium

Front 6

o Digit 1 (thumb) components

Back 6

2 phalanges= proximal and distal

Front 7

o Digits 2-5 components

Back 7

proximal, middle and distal

Front 8

o Strong fibrous band that sits in between the Thenar and Hypothenar eminences

Back 8

• Flexor Retinaculum

Front 9

Functions of • Flexor Retinaculum

Back 9

o Bridges the pisiform, hook of the hamate, tubercle of the scaphoid and trapezium
o Space between the flexor retinaculum and the carpal bones → Carpal Tunnel: allows passage of the flexor tendons and the median nerve in the hand

Front 10

Carpal tunnel contents

Back 10

-4 tendons of the flexor digitorum superficilais
-4 tendons of the flexor digitorum profundus tendon of the flexor pollicis longus muscle
-Median nerve

Front 11

o Tendons pass through the palm of the hand posterior to the superficial

Back 11

palmer arch and digital nerves

Front 12

o Tendons enter the fibrous digital sheaths on the anterior surfaces of the digits

Back 12

• 1 common flexor synovial sheath (ulnar bursa = arising from sheath of 5th digit)
• 3 digital synovial sheaths
• tendon of the flexor pollicis longus muscle has its own synovial sheath (radial bursa)

Front 13

the flexor digitorum profundus tendon passes through

Back 13

through the flexor digitorum superficialis tendon

Front 14

o Flexor digitorum profundus attaches to the

Back 14

distal phalanx

Front 15

o Flexor digitorum superficialis tendon attaches to

Back 15

the middle phalanx

Front 16

o Flexor pollicis longus muscles attaches to the

Back 16

distal phalanx of the thumb

Front 17

Carpal Tunnel Syndrome

Back 17

• Swelling of the common flexor synovial sheath may encroach on the available space in the carpel tunnel
• As a result→ median nerve is compressed, resulting in pain and paresthesia of the thumb, index and middle fingers and weakness of the thenar muscles

Front 18

Intrinsic Hand Muscles

Back 18

• Muscles that have their proximal and distal attachments within the hand
• Intrinsic muscles of the hand are located in the palm and are innervated by either the median nerve or the ulnar nerve

Front 19

• Palmar fascia is thickened to form the

Back 19

palmar aponeurosis (4 bands of longitudinal fibers, one band to each of digits 2-5) which covers the thenar and hypothenar eminences

Front 20

A. Thenar and Adductor Compartment (Superficial group besides adductor pollicis

Back 20

• Forms the thenar eminence

Front 21

Comprises

Back 21

abductor pollicis brevis, flexor pollicis brevis and opponens pollicis
o NOTE: the opponens pollicis muscle attaches to the lateral side of the entire length of the shaft of the first metacarpal bone

Front 22

adductor comparment contains

Back 22

adductor pollicis muscle (necessary for a strong grip)

Front 23

Aductor pollicies Brevis
Proximal attch.
Distal attch
innvervation

Back 23

Flexor retinaculum
proximal phalanx-radial side
recurrent branch of median C8, T1.

Front 24

Function of abductor pollicis Brevis

Back 24

Abducts thumb at MCP and CMC joints

Front 25

Opponents Pollicis
proximal attc
distal attc
innervation

Back 25

recurrent branch of median n c8,t1

Front 26

Opponens pollicis primary action

Back 26

opposes thumb at CMC joints.

Front 27

Flexor Pollicis Brevis
proximal attch
distal attch
innervation

Back 27

-Superficial head: flexor retinaculum; trapezium Deep head: trapezoid
-Prox. phalanx on the radial side
-Recurrent branch median n. C8,T1 Deep branch ofulnar n. C8.T1

Front 28

Flexor Pollicis Brevis main function

Back 28

Flexes thurnb at MCP and CMC
jt.

Front 29

Adductor Pollicis
proximal attch
distal attch
innervation

Back 29

-Oblique head: capitate, metacarpals 2 & 3 Transverse head: rnetacarpal 3
-Proximal phalanx ulnar side
-Deep branch ofulnar n. C8.T1

Front 30

Adductor Pollicis function

Back 30

Adducts thurnb at MCP and CMC jts

Front 31

B. Hypothenar Compartment (Superficial group)
• Forms the hypothenar eminence
• Contains muscles that

Back 31

that flex, abduct and oppose the little finger

Front 32

• Palmaris Brevis muscle is found superficial to the

Back 32

hypothenar muscles

Front 33

Palmaris brevis
Proximal attch
Distal attch
innervated by

Back 33

the medial aspect of the palmar aponeurosis
-skin over the hypothenar eminence
-small motor branch of the superficial branch of the ulnar nerve

Front 34

Hypothenar compartment muscles

Back 34

Palmaris Brevis
Abductor Digitr Minimi
Flexor Digiti Minirni Brevis
Opponens Digit Minimi

Front 35

Abductor Digiti Minimi
proximal
distal
innvervation

Back 35

Pisiform; tendon of FCU
-Proximal phalanx - ulnar side
-Deep branch of ulnar n. C8,T1

Front 36

Abductor digit minimi function

Back 36

Abducts little finger at MCP jt

Front 37

Flexor Digiti Minirni Brevis
prox
distal
innvernation

Back 37

-Flexor retinculum; hook of hamate
-Proximal phaianx ulnar side
-Deep branch of ulnar n. C8,T1

Front 38

Opponens Digit Minimi
prox
distal
innvervation

Back 38

-Flexor retinaculum; hook of hamate
-5"'metacarpal - ulnar side
-Deep branch of ulnar n. C8.T1

Front 39

Opponens Digit Minimi function

Back 39

Flexes little finger at MCP jtOpposes CMC jt

Front 40

The lumbricals are 4 small “worm-like” muscles that arise from

Back 40

flexor digitorum profundus tendons in the palm

Front 41

• Lumbricals I and II have a single

Back 41

head (unipennate) and are innervated by the median nerve

Front 42

• Lumbricals III and IV have two heads (bipennate) and are

Back 42

innervated by the deep branch of the ulnar nerve

Front 43

• ALL lumbricals pass to the radial side of the corresponding finger and insert onto

Back 43

the radial border of the extensor expansion (at the lateral bands)

Front 44

• Because of their proximal palmar attachment and their distal dorsal attachment lumbricals have the unique property of

Back 44

being able to flex the fingers at the MCP joint and yet extend the fingers at the IP joints (**BUT NOT AT THE SAME TIME) if the lumbricals are acting to flex the MCP joint then extensor digitorum will act to extend the IP joint

Front 45

D. Interossei
• Divided anatomically and functionally into

Back 45

dorsal (abductor) groups and palmar (adductor) groups. REMEMBER DAB and PAD

Front 46

Interossei arranged around imaginary line drawn through

Back 46

long axis of the middle finger

Front 47

• Dorsal Interossei (4 dorsal interossei)
o Insert into the extensor expansion at the base of the proximal phalanges and allows them to

Back 47

ABDUCT each digit away from the long axis of the middle finger

Front 48

o The 1st dorsal interossei= located in

Back 48

between the thumb and index finger
• Radial artery courses between the 2 heads of the 1st dorsal interossei to become the deep palmar arch

Front 49

• Palmar Interossei (3 palmar interossei)
o Insert into the

Back 49

the extensor expansion in a manner that allows them to ADDUCT each digit toward the long axis of the middle finger

Front 50

• Interossei muscles are innervated by

Back 50

the deep branch of the ulnar nerve

Front 51

Radial nerve in the hand supplies

Back 51

• Supplies NO muscles in the hand

Front 52

Radial superficial branch

Back 52

o Entirely sensory
o Arises from under the brachioradialis and supplies the dorsum of the wrist
o Then enters the hand to supply the skin of the dorsum of the thumb, radial side of the dorsum of the hand and the dorsal proximal portion of 2 ½ digits

Front 53

Median Nerve • Palmar Cutaneous Branch

Back 53

o Branches from median nerve prior to entering the hand
o Runs superficial to the flexor retinaculum →supplies the skin of the central palm

Front 54

Media nerve supploes all muscles that move the thumb except

Back 54

the adductor pollicis muscle

Front 55

• Recurrent Branch of the Median Nerve
o Supplies the ALL

Back 55

henar muscles expect ½ of flexor pollicis brevis

Front 56

• Recurrent branch is superficial and it can easily be severed by “minor” cuts over

Back 56

the thenar eminence
• If injured→ the thenar muscles are paralyzed and the thumb cant be opposed
• Medial and Lateral branches of Median Nerve

Front 57

• Medial and Lateral branches of Median Nerve

Back 57

o Supply lumbricals I and II
o Provide sensory distribution to the radial side of the palm as well as the palmar and distal dorsal surface of 3 ½ digits (radial side)

Front 58

o Medial and Lateral Branches →Common digital n. →Proper palmar digital n. (travels with

Back 58

the corresponding digital arteries from the superficial palmar arch)
• REMEMBER “1/2 LOAF” : innervates Lumbricals I-II, Opponens pollicis brevis, Abductor pollicis brevis and ½ Flexor pollicis brevis

Front 59

C. Ulnar Nerve
• Enters the wrist

Back 59

wrist superficial to the flexor retinaculum after emerging from under the carpi ulnaris
• Enter the hand via the “Tunnel of Guyon” MEDIAL to the ulnar artery

Front 60

• Superficial Branch of ulnar nerve

Back 60

o Gives off a small motor branch to the palmaris brevis muscle
o Gives off a Palmar Cutaneous Branch: supplies the skin of the ulnar side of the palm

Front 61

• Dorsal Cutaneous Branch of ulnar nerve

Back 61

o Sensory branch of the ulnar nerve and branches off before the wrist
o Supplies the skin of the medial half of the dorsum of the hand as well as the dorsal and palmar surface of 1 ½ fingers (ulnar side)

Front 62

• Deep Branch of the Ulnar Nerve

Back 62

o Supplies the hypothenar muscles, medial 2 lumbricals (III-IV), the adductor pollicis brevis, the deep head of the flexor pollicis brevis and ALL of the interrosei (dorsal and palmar)

Front 63

• 2 palmar arches supply the palm of the hand

Back 63

o Superficial Palmar Arch: formed mainly by the ulnar artery
o Deep Palmar Arch: formed mainly by the radial artery

Front 64

A. Ulnar Artery
o Enters the hand LATERAL to the

Back 64

ulnar nerve at GUYON’s CANAL

Front 65

Ulnar artery divides into

Back 65

into 2 terminal branches→ Superficial palmar arch and the deep palmar arch

Front 66

• Superficial Palmar Arch

Back 66

• Gives rise to 3 Common Palmar Digital arteries
• Each Common divides into a pair of Proper Palmar Digital Arteries for fingers 2-4
• The superficial palmar arch is completed by a smaller contribution from the superficial palmar branch of the radial artery

Front 67

• Deep Palmar Arch

Back 67

• The deep palmar branch of the ulnar artery forms an anastomosis with the radial artery to form the deep palmar arch

Front 68

B. Radial Artery
o Crosses the floor of the anatomical snuff box and enters the palm by passing between

Back 68

first the 2 heads of the 1st dorsal interrosei and then the 2 heads of the adductor pollicis muscles

Front 69

o Deep Palmar Arch
• Divides to form

Back 69

3 metacarpal aa., 1 princeps pollicis a., and 1 radialis indicis a