Hand

Question 1

Name bones of hand/wrist. Proximal row. Distal row.

Answer 1

Proximal Row: Scaphoid, Lunate, Triquetrum, Pisiform

Distal Row: Hamate, Capitate, Trapezoid, Trapezium

Question 2

What is the most frequently fractured bone in wrist?
What is the most frequently dislocated carpal bone?
Which is the largest carpal bone? First to ossify?

Answer 2

Scaphoid most frequently fractured
Lunate is the most frequently dislocated carpal bone
Capitate is largest and first to ossify

Question 3

What cutaneous nerves affect the tips of fingers? (1-3 and half of 4th)

Answer 3

median nerve

Question 4

Describe deep palmar fascia and palmar aponeurosis.

Answer 4

deep palmar fascia- continuous proximally with the antebrachial fascia, thick in palm where forms palmar aponeurosis
palmar aponeurosis- strong, heavy, dense, well-defined triangular layer of deep fascia in middle of palm

Question 5

How does Dupuytren’s Contracture manifest?

Answer 5

manifests as progressive fibrosus, typically produces abnormal bands of fibrous tissue that extend from the aponeurosis to the bases of the phalanges pulling one or more digits into marked flexion at the metacarpophalangeal joints so they cannot be straightened

Question 6

What are the 10 structures that pass through the carpal tunnel?

Answer 6

flexor digitorum superficialis (4 tendons)
flexor digitorum profundus (4 tendons)
flexor pollicis longus (1 tendon)
median nerve

Question 7

What are the posterior and anterior boundaries of the carpal tunnel?

Answer 7

anterior boundary is formed by the flexor retinaculum

posterior boundary is formed by the carpal bones

Question 8

What is the first thing affected when there is swelling in carpal tunnel/increase in pressure? What will result?

Answer 8

Median nerve is first thing/most affected (softest)

sensory loss

Question 9

What artery goes around the thumb and comes in backside?

Answer 9

radial artery

Question 10

How does carpal tunnel syndrom occur?
What are possible causes?
Clinical manifestations?

Answer 10

results from any lesion that will decrease the size of carpal tunnel
possible causes: fluid retention, infection, excessive exercise
cavity instead of bulge (wasting of the thenar muscles)

Question 11

Describe thenar compartment of hand.

What happens if median nerve cut?

Answer 11

OAF
opponens pollicis, abductor pollicis brevis, flexor pollicis brevis
ALL innervated by median n. (if cut, loss of ability to grasp)

Question 12

Which muscles allow you to touch tips vs pads of fingers?

Answer 12

tips- flexors only

pads-lumbricals and flexors

Question 13

Describe hypothenar compartment of hand

Answer 13

OAF
opponens digiti minimi, abductor digiti minimi, flexor digiti minimi
all innervated by ULNAR nerve.

Question 14

Describe the innervation of the lumbricals.

Answer 14

1 and 2 by median nerve

3 and 4 by ulnar nerve

Question 15

What is the function of lumbricals?

Answer 15

extend the proximal and distal interphalangeal joints
will help extend a flexed finger - due to insertion on EXTENSOR expansion. this allows pinching on the pulp of fingers (not the tips)
Flex the hand (metacarpophalangeal joints)

Question 16

Dorsal interossei

Answer 16

DABS (4)
4 dorsal interossei between the metacarpal bones
Dorsal interossei ABduct (pull fingers apart)
Flex the hand (metacarpophalangeal joints)

Question 17

Palmar interossei

Answer 17

PAD (3)
3 palmar interossei
Palmar interossei ADduct

extension and adduction of proximal and distal IP joints
flex the hand (metacarpophalangeal joints)

Question 18

USRD

Answer 18

Ulnar superficial, radial deep
arterial supply of deep palmar arch-radial
superficial palmar arch-ulnar

Question 19

Describe the superficial branch of the ulnar artery.

Answer 19

becomes the superficial palmar arch
anastamoses with superficial branch of radial artery
as it extends across the palm, gives off digital branches to fingers

Question 20

What branches does the superficial palmar arch give off to fingers?

Answer 20

Gives off digital branches to fingers:
common palmar digital arteries pass between metacarpals
proper palmar arteries run on either side of digits 2-5

Question 21

Describe the deep branch of the ulnar artery

Answer 21

passes between abductor digiti minimi and flexor digiti minimi
anastomoses with deep palmar arch

Question 22

What does the deep palmar arch anastomose with?

Answer 22

deep palmar arch (radial) will eventually anastamose with deep branch of ulnar artery.

Question 23

Describe the branches off the radial artery to palmar areas of hand:

Answer 23

gives off princeps pollicis artery to supply medial side of thumb
gives of radialis indicis artery to supply lateral side of 2nd digit

Question 24

Describe median nerve C5-C8, T1. Where does it enter hand?
Recurrent (Thenar branch)
What does it become?
What does it provide to palmar aspect of fingers?

Answer 24

enters hand under flexor retinaculum through the carpal tunnel.

Recurrent (Thenar Branch):
first branch distal to flexor retinaculum
enters the thenar eminence
innervates 1/2 LOAF

Will become common palmar digital nerves and then proper palmar digital nerves
-provides cutaneous senstaion to the palmar asepct of the lateral 3 1/2 fingers AND dorsal aspect of the same fingers distally (nail bed)

Question 25

Describe Ulnar nerve (C8, T1)

Answer 25

enters hand via canal of Guyon (ulnar canal)
palmar cutaneous branch to medial side of palm
dorsal cutaneous branch extends distally across dorsum of hand, dorsal surfaces of the medial 1 1/2 digits)

distal to flexor reinaculum, gives off 2 branches
Superficial branch
deep branch (innervates palmar brevis, 3 and 4th lumbricals, hyopthenar muscles (OAF), dorsal and palmar interosssei, adductor pollicis)

Question 26

Radial nerve (C5-C8, T1)

Answer 26

cutaneous sensation to dorsal aspect of lateral 3 and half digits proximal to DIP joint.
NO MOTOR BRANCHES IN HAND.
just sensory!
(superficial branch enters dorsum of hand by passing over anatomical snuff box)