The hand Flashcards
1
Q
what kind of joint is the CMC joint at the base of the thumb
A
synovial saddle joint
2
Q
the synovial saddle joint at the base of the thumb permits
A
opposition of the thumb
3
Q
the MCP joints of all the digits are
A
synovial condyloid joints
4
Q
what movements are allowed at the MCP joints
A
flexion extension abduction adduction small degree of circumduction
5
Q
what type of joints are the IP joints
A
synovial hinge
6
Q
what movements are allowed at IP joints
A
flexion and extension of the fingers
7
Q
what type of joints are between carpal bones
A
synovial plane - small gliding movements allowed
8
Q
what are the bones of the hand
A
carpals
metacarpals
phalanges - proximal, middle, distal
(thumb doesnt have a middle phalanx)
9
Q
what is the first structure seen immediately beneath the skin of the palm
A
palmar aponeurosis
10
Q
what does the palmar aponeurosis do
A
tough connective tissue layer that adheres to the skin of the palm - it helps to hold the skin of the palm in place during movement to prevent skin from slipping and loss of grip
also protects the delicate nerves and vessels of the palm
11
Q
what tightens the palmar aponeurosis
A
palmaris longus from the forearm
12
Q
where is palmaris brevis
A
thin intrinsic muscle that lies superficial to the muscles of the hypothenar eminence
13
Q
what is the origin and insertion of palmaris brevis
A
palmar aponeurosis and flexor retinaculum to dermis
14
Q
what is the function of palmaris brevis
A
grip
15
Q
what is the innervation of palmaris brevis
A
ulnar nerve (superficial C8,T1)
16
Q
what nerve innervates most of the muscles of the hand
A
ulnar nerve
17
Q
what is the difference between intrinsic and extrinsic muscles of the hand
A
intrinsic are entirely within the hand
extrinsic muscles enter the hand from the forearm
18
Q
what are the deepest muscles of the hand called
A
interossei because they lie between the metacarpal bones of the hand
19
Q
the thumb (lateral) side of the hand is dominated by what nerve
A
median - some but not all muscles are supplied by it
20
Q
the little finger (medial) side of the hand is dominated by
A
ulnar nerve
21
Q
the deepest intrinsic muscles of the hand are supplied by
A
ulnar nerve
22
Q
how many muscles make up the thenar eminence
A
3 - two superficial and one deep
23
Q
the muscles of the thenar eminence all act on what
A
CMC joint of the thumb
24
Q
what muscle lies on the lateral side of the eminence
A
abductor pollicis brevis
25
what does abductor pollicis brevis do
acts to pull the thumb away from the plane of the palm
26
what muscle is medial in the thenar eminence
flexor pollicis brevis
27
what does flexor pollicis brevis do
acts to bend the joint of the thumb in the same plane as the palm
28
the long abductor and flexor muscles originate where
forearm
29
flexion of the thumb is dominated by what nerve
median nerve
30
abduction of the thumb is what nerve
both radial and median
31
what is the deepest muscle in the thenar eminence
opponens pollicis
32
what does opponens pollicis do
acts to oppose the thumb by pulling the base of the thumb across the palm allowing the pulp of the thumb to touch the pulp of other digits
33
opposition of the thumb is controlled by what nerve
median nerve
34
the muscles of the thenar eminence are supplied by
median nerve - although sometimes the ulnar nerve may send innervation to flexor pollicis brevis
35
what branch of the median nerve supplies the thenar eminence
recurrent branch of the median nerve - the median nerve sends a branch that passes backwards towards the thenar eminence
36
what are the attachments of abductor pollicis brevis
scaphoid and trapezium to base of proximal phalanx of thumb
37
abductor pollicis brevis does what
CMC joint abduction
38
what nerve supplies abductor pollicis brevis
median nerve (recurrent C8, T1)
39
what are the attachments of the flexor pollicis brevs
flexor retinaculum, capitate, trapezium to base proximal phalanx of thumb
40
what is the function of flexor pollicis brevis
CMC joint flexion
41
what is the innervation of flexor pollicis brevis
median (recurrent) and some texts also say ulnar nerve (C8,T1)
42
what are the attachments of opponens pollicis
trapezium to first metacarpal
43
what is the function of opponens pollicis
CMC joint opposition
44
what is the innervation of opponens pollicis
median nevre (recurrent C8, T1)
45
what is the other intrinsic muscle of the thumb
adductor pollicis
46
is adductor pollicis part of the thenar eminence
no
47
what are the attachments of adductor pollicis
transverse head from 3rd metacarpal; oblique head from capitate and 2nd/3rd metacarpals to base of proximal phalanx of thumb
48
what are the functions of adductor pollicis
adduction of CMC joint of thumb
| flexion of MCP joint of thumb
49
what is the innervation of adductor pollicis
ulnar nerve (deep C8, T1)
50
adductor pollicis is one of the deep/superficial intrinsic muscles
one of the deeper layer
51
the muscles of the hypothenar eminence do what
move the MCP joint of the little finger
52
the muscles of the hypothenar eminence are all supplied by the
ulnar nerve
53
what is the medial muscle in the hypothenar eminence
abductor digiti minimi
54
what is the lateral muscle in the hypothenar eminence
flexor digiti minimi
55
what are the attachments of abductor digiti minimi
pisiform bone to base of 5th proximal phalanx and dorsal digital expansion
56
what is the function of abductor digiti minimi
abduction and flexion of MCP joint of little finger
57
what is the innervation of abductor digiti minimi
ulnar nerve (deep C8, T1)
58
what are the attachments of flexor digiti minimi
hamate, flexor retinaculum to base of 5th proximal phalanx
59
what is the function of flexor digiti minimi
flex MCP joint of little finger
60
what is the innervation of flexor digiti minimi
ulnar nerve (deep C8, T1)
61
what are the attachments of opponens digiti minimi
hamate and flexor retinaculum to 5th metacarpal
62
what is the function of opponens digiti minimi
weak opposition of little finger
63
what is the innervation of opponens digiti minimi
ulnar nerve (deep C8, T1)
64
why can opponens digiti minimi not allow pulp-to-pulp opposition in the same way that opponens pollicis can for the thumb
the CMC joint at the base of the little finger is synovial plane not synovial saddle so it cant pull the base of the finger towards the palm in the same way
65
what are the attachments of the lumbricals
4 small muscles that go from tendons of flexor digitorum profundus to the dorsal expansion of index, middle, ring and little fingers
66
what is the function of the lumbricals
MCP joint flexion and IP joint extension for digits 2-4
67
what nerve supplies the lateral 2 lumbricals (1 and 2)
median nerve (digital C8, T1)
68
what nerve supplies the medial 2 lumbricals (3 and 4)
ulnar nerve (deep C8, T1)
69
the ulnar nerve supplies all the intrinsic muscles of the hand except for what
LOAF
- lateral 2 lumbricals
- opponens pollicis
- abductor pollicis brevis
- flexor pollicis brevis
all supplied by median nerve
70
where are the palmar interossei
between metacarpal bones
71
where do the palmar interossei insert
proximal phalanx and dorsal expansion of the fingers
72
are there interossei for the thumb
no it already has its own abductor and adductor muscles
73
the interossei are innervated by what
deep branch of the ulnar nerve (C8, T1)
74
what is the function of the palmar interossei
move the fingers towards the midline
75
how many palmar interossei are there
3 - middle finger is already in midline
76
what are the attachments of the 1st palmar interossei
from 2nd metacarpal to base of 2nd proximal phalanx and dorsal expansion
77
what are the attachments of the 2nd palmar interossei
from 4th metacarpal to base of 4th proximal phalanx and dorsal expansion
78
what are the attachments of the 3rd palmar interossei
from 5th metacarpal to base of 5th proximal phalanx and dorsal expansion
79
what is the function of the palmar interossei
adduction towards middle finger
| also flex MCP and extend IP
80
what is the function of the dorsal interossei
move the fingers away from the midline to spread the fingers
MCP flexion and IP extension
81
how many dorsal interossei are there
4
82
the first dorsal interossei moves the
index finger
83
the second and third dorsal interossei move the
middle finger
84
the fourth dorsal interossei moves the
ring finger
85
why does the little finger not have a dorsal interossei
already has abductor digiti minimi in the hypothenar eminence
86
what are the attachments of the 1st dorsal interossei
sides of 1st and 2nd metacarapals to 2nd proximal phalanx and dorsal digital expansion
87
what are the attachments of the 2nd dorsal interossei
sides of 2nd and 3rd metacarpals to 3rd proximal phalanx and dorsal digital expansion
88
what are the attachments of the 3rd dorsal interossei
sides of 3rd and 4th metacarpals to the 3rd proximal phalanx and dorsal digital expansion
89
what are the attachments of the 4th dorsal interossei
sides of 4th and 5th metcarpals to 4th proximal phalanx and dorsal digital expansion
90
the 1st dorsal interossei moves the
index finger
91
the 2nd dorsal interossei moves the
middle finger
92
the 3rd dorsal interossei moves the
middle finger
93
the 4th dorsal interossei moves the
ring finger
94
what is the innervation of the dorsal interossei
ulnar nerve (deep C8, T1)
95
DAB
Dorsal interossei ABduct
96
PAD
Palmar ADduct
97
what muscles are found between the webspace between the thumb and the index finger
first dorsal interosseous muscle and adductor pollicis
98
from the palmar surface what muscle do you see in the thumb and index finger webspace
adductor pollicis
99
from the dorsal surface what muscle do you see in the thumb and index finger webspace
first dorsal interosseous muscle
100
what is the blood supply to the hand
radial and ulnar arteries anastomose to supply the hand
101
where does the ulnar artery cross the wrist
above the carpal tunnel
102
the ulnar artery forms most of the
superficial arch of the palm
103
where does the radial artery pass into the hand
in the floor of the anatomical snuffbox
104
the radial artery forms most of the
deep palmar arch
105
where do the radial and ulnar arteries anatomose
via the palmar arches
106
what is the blood supply of the fingers
digital branches supply the fingers and lie on lateral sides of each digit to prevent damage to vessels during flexion and extension
107
does everyone have a superficial arch
it can vary and some people dont have a communication between the radial and ulnar arteries
108
does everyone have a deep palmar arch
it is very small and little variation is seen in this structure
109
describe the course of the radial artery
through the anatomical snuffbox over the scaphoid and trapezium into hand, passes between the heads of adductor pollicis to anastomose with the ulnar artery
110
in addition to the deep arch the radial artery also forms
the princeps pollicis artery - the largest artery to the thumb
111
in addition to the deep arch and princeps pollicis the radial artery also usually forms what
a vessel to the index finger
112
what surrounds tendons of flexor muscles as they pass through the palm
small synovial sheaths - synovial membrane plus fluid
113
the synovial sheaths extend where
around tendons at wrist, palm and into digits
114
what are the small anatomical spaces created by the synovium
the palmar and thenar spaces
115
what is the clinical significance of the palmar and thenar spaces
spread of infection across the palm
116
what nerve dominates the thumb (lateral) side of the hand
median nerve
117
what nerve dominates the little finger (medial) side of the hand
ulnar nerve
118
what does the median nerve supply in the hand
muscles of the thenar eminence and the lumbricals to the index and middle fingers
119
what does the ulnar nerve supply in the hand
muscles of the hypothenar eminence and the lumbricals to the ring and little fingers as well as to adductor pollicis and all of the dorsal and palmar interossei
120
what nerves carry sensory innervation to the hand
radial
ulnar
median
121
what does the median nerve give sensory innervation to
skin of the lateral side of the palm, the palmar surface of the thumb and the lateral two and half digits (index middle and half of ring) and the dorsum of these fingers and thumb to approximately between the DIP and PIP joints
122
what does the ulnar nerve give sensory innervation to
skin of both the palmar and dorsal surfaces of the medial side of the palm and the medial one and half fingers (little and half of ring)
123
what does the radial nerve supply sensory innervation to
skin on the thenar eminence and the lateral side of the dorsum of the hand
124
what does the musculocutaneous nerve terminate as
lateral cutaneous nerve of the forearm
125
the medial cutaneous nerves of the arm and forearm are direct branches of what
medial cord of the brachial plexus
126
what is the sensory innervation of the axillary nerve
badge patch area - the superior lateral part of the arm
127
what is a dermatome
the expression of a single spinal root on the skin
128
dermatome of badge patch area
C5 carried by axillary nerve
129
dermatome of the pad of the thumb (part on the palmar surface used for pulp-to-pulp opposition)
C6
130
dermatome of pad of the middle finger
C7 (7 up)
131
dermatome of pad of the little finger
C8 (maaaate)
132
dermatome of medial side of elbow
T1
