Lecture 13: Hand

Question 1

1

Answer 1

1

Question 2

what type of joint are metacarpo-phalangeal joints and what movement does it allow?

Answer 2

condyloid joints
flexion/extension
Adduction/abduction

Question 3

what muscles does musculocutaneous nerve innervate ?

Answer 3

The musculocutaneous nerve innervates the three muscles of the anterior compartment of the arm: the coracobrachialis, biceps brachii, and brachialis muscles. It is also responsible for cutaneous innervation of the lateral forearm.

Question 4

what type of joint are interphalangeal joints and what movement does it allow?

Answer 4

hinge joints
flexion/extension only

Question 5

what do deep transverse metacarpal ligaments attach to?

Answer 5

to the edges of the palmar ligaments of the metacarpophalangeal joints

Question 6

where are palmar ligaments present in the hand?

Answer 6

metacarpophalangeal joints
interphalangeal joints

Question 7

what forms the floor of fibro-osseous tunnels?

Answer 7

palmar lig

Question 8

where do interossei muscles pass in relation to deep transverse metacarpal ligaments?

Answer 8

pass on the dorsal side

Question 9

where do lumbrical muscles pass in relation to deep transverse metacarpal ligaments?

Answer 9

on the palmar side( ventrally or anteriorly)

Question 10

what are the 3 major compartments of the palm and what muscles and tendons do they house?

Answer 10

central( houses the long flexor tendons, lumbricals etc)

lateral(houses thenar muscles)

medial( houses the hypothenar muscles)

Question 11

what muscles contribute to spreading the digits?

Answer 11

dorsal interossei abduct digits 2, 3, 4
abductor digit minimi(AbDM) act on the little finger(5th digit)

extensor pollicis brevis and longus extend the thumb in the same plane as palm

(abduction of fingers but extension of the thumb)

Question 12

what muscles abduct the thumb in a plane perpendicular to the palm?

Answer 12

abductor pollicis longus( AbPL)
abductor pollicis brevis( AbPB)

Question 13

what muscles adduct the digits?

Answer 13

palmar interossei act on 1st, 2nd, 4th, and 5th digits to adduct the digits

dorsal interossei are responsible for moving the 3rd digit if required and adductor pollicis will act on the thumb to add strength to the movement

Question 14

DIMAB and POMAD

Answer 14

Question 15

Answer 15

Question 16

what nerve innervates adductor pollicis?

Answer 16

ulnar nerve(deep branch)

Question 17

what nerve innervates lumbricals?

Answer 17

2 bipennate( 3rd and 4th lumbricals): ulnar n

2 unipennate( 1st and 2nd lumbricals): median n

Question 18

what nerve innervates thenar muscles?

Answer 18

median n

Question 19

innervation of the thenar muscles?

Answer 19

Recurrent branch
median n

Question 20

innervation of the thenar muscles?

Answer 20

median n

Question 21

innervation of the hypothenar muscles?

Answer 21

ulnar n (deep branch)

Question 22

how are metacarpophalangeal joints flexed?

Answer 22

there is no forearm muscle that inserts into the base of the proximal phalanges

flexion partially accomplished by FDS and FDP maximally shortening, as in making a tight fist, but fine control is brought about by the actions of the interossei and lumbricals , with their insertions into the edges of the dorsal digital expansion hood as this narrows over the proximal phalanx

Question 23

what brings about the flexion of the IP joints?

Answer 23

insertion of the tendons of FDS and FDP into the bases of the middle and distal phalanges respectively

Question 24

what muscles act to achieve opposition of the thumb?

Answer 24

opponens pollicis(OP)
opponens digit minimi(ODM)

act together with other intrinsic hand muscles

Question 25

what muscles have the ability to flex the MCP joints at the same time as extending the IP joints( e.g making a “pinch grip”)

Answer 25

interossei and lumbricals

Question 26

thenar muscles

Answer 26

abductor pollicis brevis
flexor pollicis brevis
opponens pollicis

Question 27

what muscles extend the thumb?

Answer 27

extensor pollicis brevis and longus

Question 28

what muscles abduct the thumb?

Answer 28

perpendicular to palm

abductor pollicis longus(AbPL)
anductor pollicis brevis(AbPB)

Question 29

what is another common name for the 1st Palmar interossei(PI) acting on the thumb?

Answer 29

often referred to as part of flexor pollicis brevis

Question 30

what nerves do common palmar digital n. branch off from?

Answer 30

ulnar and median nerves

Question 31

what do the dorsal branches of the proper palmar digital nerves innervate?

Answer 31

the skin on the back of the fingers and nail

Question 32

what does the dorsal cutaneous branch of the ulnar nerve innervate?

Answer 32

back skin of the 1.5 medial digits

Question 33

what nerve innervates the back skin of the lateral 3.5 digits?

Answer 33

the superficial branch of radial n

Question 33

what nerve innervates the back skin of the lateral 3.5 digits?

Answer 33

the superficial branch of radial n

Question 34

what does the palmar cutaneous branch of median n supply?

Answer 34

the skin of the palmar aspect over the lateral side of the hand

Question 35

are palmar cutaneous branches of ulnar and median nerve affected by carpal tunnel syndrome?

Answer 35

no. branch before the flexor retinaculum

Question 36

Where do you prick to test for carpal tunnel syndrome?

Answer 36

prick 2nd and 3rd digits supplied by the median nerve
(a median nerve is the only nerve that goes through the carpal tunnel)

Question 37

what are the muscles in the hand supplied by the median nerve?

Answer 37

thenar muscles
Lateral 2 lumbricals(unipennate)

5 in total

Question 38

what are the muscles in the hand innervated by the deep branch of the ulnar nerve?

Answer 38

-hypothenar muscles( abductor digiti minimi; flexor digiti minimi; opponens digiti minimi)

• dorsal interossei(4)
  -palmar interossei(4)
  -2 medial lumbricals
  -adductor pollicis

Question 39

Answer 39