Upper Limb Flashcards
1
Q
what are the two essential functions of the brachial plexus?
A
supplies motor & sensory innervation to shoulder and arm
2
Q
How is a nerve plexus formed?
A
Nerve fibres from two or more spinal segments intermingle then segregate to travel together to a common anatomical region
3
Q
where do the brachial plexus nerves originate from in the spinal cord, what section?
A
C5-T1
4
Q
what is the path of the fibres from spinal cord to target?
A
Roots, trunks, divisions, cords, terminal branches
5
Q
how many roots are there and their origin from spinal cord?
A
5,
C5, C6, C7, C8, T1
6
Q
how are the three trunks formed?
A
C5 and C6 = superior trunk
C7 = middle trunk
C8 and T1 = inferior trunk
7
Q
how many divisions are there and what are they called?
A
6 divisions
2 for each trunk
Anterior and posterior for each trunk
8
Q
how many cords are there and their names and why
A
3
lateral, posterior, medial
named according to position relative to axillary artery
9
Q
how each cord is formed:
A
lateral = from both anterior divisons from upper and middle trunk
posterior = from all three posterior divisions
medial = from anterior division from lower trunk
10
Q
what are the 5 terminal branches of the brachial plexus
A
musculocutaneous nerve
axillary nerve
radial nerve
median nerve
ulnar nerve
11
Q
how is each terminal branch formed (from what cord)
A
musculocutaneous = lateral cord
axillary = posterior cord
radial = posterior cord
median = lateral and medial cord
ulnar = medial cord
12
Q
what is a good reference point of the brachial plexus
A
the M characteristic formed by terminal branches of lateral and medial cords
13
Q
C5 & C5, C6, C7
what branches arise from the brachial plexus roots? (2)
A
Dorsal scapular nerve - C5
long thoracic nerve - C5, C6, C7
14
Q
both come from upper trunk
what branches arise from the brachial plexus trunk? (2)
A
Suprascapular nerve = upper trunk
Nerve to subclavius = upper trunk
15
Q
what nerves arise from the brachial plexus divisions?
A
No nerves!
16
Q
lateral cord = 1, posterior cord = 3, medial cord = 3
what nerves arise from the brachial plexus cords? (7)
A
Lateral cord = lateral pectoral nerve
posterior cord = upper, middle and lower subscapular nerve
medial cord = medial pectoral nerve, medial brachial cutaneous nerve, medial antebrachial cutaneous nerve
17
Q
what happens when you fall on your head?
how can upper brachial plexus injury occur?
A
extreme lateral flexion of head, especially when shoulder is depressed
18
Q
what does upper brachial plexus injury result in:
A
Erb-Duchenne Paralysis
19
Q
what are characteristics of Erb-Duchenne Paralysis (3)
A
arm hangs limp at side
internally rotated
forearm also pronated
20
Q
clinging on something with one arm when falling from somewhere
how can lower brachial plexus injury usually occur?
A
extreme abduction of the upper arm
21
Q
what does lower brachial plexus injury usually effect in terms of spinal cord segments
A
C8 and T1
22
Q
what does lower brachial plexus injury usually result in?
A
Klumpke’s Paralysis
23
Q
what are characteristics of Klumpke’s paralysis
A
a “claw hand”, fingers are flexed in claw position
24
Q
what are the two sensory signs of nerve injury
A
Loss of sensation
Paraesthesia
25
what is paraesthesia?
tingling, burning, or pins and needles sensation
26
# terminal branches of brachial plexus, one other
what are frequently injured nerves located around the shoulder and arm region (6 nerves)
Long thoracic nerve
the 5 terminal branches of the brachial plexus:
axillary
radial
musculocutaneous
ulnar
median
27
where is the long thoracic nerve found, & what is supplies?
travels inferiorly on lateral chest wall to supply innervation to serratus anterior muscle
28
why is the long thoracic nerve easily injured? (2)
1. located on superficial surface of muscle
2. covered only by skin and subcutaneous fat
29
what is the classic sign of thoracic nerve injury?
winging of the scapula
30
how is winging of the scapula tested? (2)
patient supports weight with hands while leaning on wall
if injured, medialy boarder of scapula will make obvious dorsal protrusion
31
# stability of scapula muscle
why does injury of the long thoracic nerve cause winging of the scapula? (2)
The nerve innervates the Serratus anterior
this muscle is crucial for movement and stability of the scapula.
32
# process involves removal of one or both breasts
what type of operation typically causes long thoracic nerve injury?
Mastectomy:
surgical procedure involving removal of one or both breasts usually due to cancer
33
what is the axillary nerve a terminal branch of?
the posterior cord
34
# innervates deltoid and teres minor muscles
square type space
location of the axillary nerve: (3)
travels posterior through quadrangular space in shoulder
around surgical neck of humerus
35
what is the surgical neck of the humerus? (1)
the narrow part just below the humeral head
36
what is the motor innervation of the axillary nerve? (2)
Deltoid
Teres Minor
37
what is the sensory innervation of the axillary nerve? (1)
patch of skin over lateral-posterior shoulder
38
Typical causes of axillary nerve injury: (2)
Fracture of upper neck of humerus
shoulder dislocation
39
what does axillary nerve injury result in terms of motor control? (3) which muscle causes this?
loss of shoulder abduction above 15 degrees (deltoid)
weakened external rotation of humerus (teres minor)
weakened stability of shoulder joint (Teres minor)
40
what is the sensory effect of axillary nerve injury? (1)
loss of sensation over posterior-lateral aspect of shoulder
41
what is the radial nerve a terminal branch of?
posterior cord
42
path of radial nerve: (5)
travels posterior around body of humerus
lies in radial groove
just distal to elbow joint, divides into many branches
extends all the way to lateral aspect of hand
43
what is the radial groove of the humerus? (2)
a shallow groove on the posterior aspect of the humerus
serves as a pathway for radial nerve
44
what is the motor innervation of the radial nerve? (3)
all extensor compartment muscles of arm and forearm
brachioradialis
supinator muscle
45
where is the brachioradilais muscle found (1) and what does it do? (3)
found on lateral side of forearm
flexion and extension of forearm
assist in flexion of elbow
46
what is the sensory innervation of the radial nerve?
skin on dorsal surface (tricep side) of all arm and hand
47
what is the name of the extension of the radial nerve that supplies the brachioradialis
Posterior interosseus nerve (PIN)
48
what are characteristics of radial nerve injury? (2)
wrist drop due to loss of extensor muscles in forearm
loss of elbow extension
49
what causes radial nerve injury? (2)
fracture of middle of humerus
nerve compression
50
how can the radial nerve be compressed? (2)
crutches
sleeping with companions head resting on arm
51
# which cord?
what is the musculocutaneous nerve a terminal branch of?
lateral cord
52
# 3 muscles in flexor compartment of upper arm
what does the musculocutaneous nerve provide motor innervation to?
coracobrachialis
brachialis
biceps brachii
53
what does the musculocutaneous nerve provide sensory innervation to?
lateral forearm
## Footnote
the specific branch of this nerve is called the antebrachial/lateral cutaneous nerve
54
# has two names
what is the branch of the musculocutaneous nerve that supplies the lateral aspect of forearm
antebrachial/ lateral cutaneous nerve
55
what does damage to the musculocutaneous nerve result in (motor)? (2)
loss of elbow flexion
weakened elbow supination
56
# which cord
what is the ulnar nerve a terminal branch of?
Medial cord
57
what does the ulnar nerve innervate in the upper arm?
no structures!
58
# only muscles
what does the ulnar nerve innervate in forearm? (2)
flexor carpi ulnaris muscle
1/2 flexor digitorum profundus muscle
59
where is the flexor carpi ulnaris muscle found?
medial side of forearm
60
# involved in hand movement
what does the flexor carpi ulnaris muscle do? (2)
flex & adduct hand at wrist joint
61
# how middle is it in forearm?
where is the flexor digitorum profundus muscle found? (2)
deep layer of anterior compartment of forearm
medial in forearm, but slightly on side of ulna
62
# important in rock climbing!
what does the flexor digitorum profundus muscle do? (1)
flexing the distal phalanges of the fingers - all fingers
63
# I have injured it section of it
passage of the ulnar nerve (4)
travels medial to humerus
passes through cubital tunnel
runs medial in forearm
terminates in medial aspect of hand
64
# i have injured it!
what is the cubital tunnel?
| what bones form it, what tissue covers it, what nerve travels through
a tunnel formed by the **medial epicondyle of the humerus** & the **olecranon process** of the ulna.
reinforced by a fibrous band of connective tissue called **cubital retinacululm**
the ulna nerve passes through here
65
what is the sensory innervation of the ulnar nerve? (3)
medial 1/3 of hand, pinky and ring finger
66
how is the ulnar nerve commonly injured? (2)
entrapment as is passes medial lower end of humerus
fracture of lower end of medial humerus
67
what does injury of the ulnar nerve cause?
Tardy Ulnar Palsy
Claw hand - in ring and pinky finger
68
what is tardy Ulnar palsy? (2)
Paraesthesia of ring and pinky finger
los of fine motor control of these digits
69
# is the middle "M" characteristic
what is the median nerve a terminal branch of?
medial and lateral cord
70
which structures in the upper arm does the medial nerve supply?
none!
71
passage of the median nerve (3)
medial to humerus
crosses to lateral side at lower end of humerus
gives off two nerve branches here
72
what two nerve branches does the median nerve give off?
Anterior interosseus nerve (AIN)
Median nerve proper
73
# motor innervation to deep forearm muscles
what does the Anterior interosseus nerve (AIN) do? (3)
motor innervation to three muscles of forearm:
1. **flexor pollicis longus
2. lateral half of flexor digitorum profundus
3. pronator quadratus**
74
what does the flexor pollicis longus do? (1)
flexes thumb at interphalangeal joint (knuckle joint)
75
# hints in the name!
what does the pronator quadratus do? (1)
pronates forearm
76
# is a branch of the median nerve. 3 muscles in forearm, 2 in hand
what muscles does the median nerve proper innervate ?
forearm muscles:
* pronator teres
* Flexor carpi radialis
* palmaris longus
hand muscles:
* Thenar muscles
* lumbricals
77
# hint is in the name
what does pronator teres do?
assists in pronates forearm
78
# radialis!
what does flexor carpi radialis do? (2)
flexs and abducts hand at wrist joint
79
# hint is in name - palm
what does the palmaris longus do? (1)
aids in flexion of hand at wrist
80
what is the sensory innervation of the median nerve proper (4)
palmar aspect of:
1. thumb
2. index finger
3. middle finger
4. lateral aspect of ring finger
81
what is median nerve injury mostly associated with? (1)
carpal tunnel syndrome
82
wht is carpal tunnel syndrome? (2)
the medial nerve is entrapped as it enters wrist under **transverse carpal ligament**
causes pararesthesia and pain along sensory innervation of medial nerve
83
# think about passage of each terminal branch of brachial plexus
what 4 nerves surround the axillary artery as it emerges from beneath pectoralis minor
musculocutaneous
median
ulnar
radial
84
what nerves supply flexor and pronator muscles in the forearm? (2)
ulnar nerve
median nerve
85
# what are the compartments and what they do?
how are the muscles of the upper arm arranged?
posterior compartment = extensor
anterior compartment = flexor
86
what is the name of the barrier between anterior and posterior compartments of upper arm, and what is it?
**intermuscular setpum:
** fibrous barrier that separates different muscle compartments within arm *
87
# BBC
what are the three anterior muscles of the upper arm?
Biceps Brachii
Brachialis
Coracobrachialis
88
What are the two heads of the Biceps Brachii and there position relative to each other:
Long head - more lateral
Short head - medial
89
origin and insertion of both heads of biceps brachii:
Short head:
* origin = coracoid process of scapula
Long head:
* origin = supraglenoid tubercle of scapula
common insertion = radial tuberosity
90
Coracobrachialis origin and insertion
origin = coracoid process
insertion = midshaft of anterior humerus
91
coracobrachialis function (1)
weak adductor of the arm
92
brachialis origin and insertion
origin = distal part of anterior humerus
insertion = ulna tuberosity and ulnar coracoid process
93
function of the brachialis (1)
elbow flexion
94
Why is the Biceps Brachii a supinator of the forearm as well? (1)
due to its tendon attachment along back of radial tuberosity
95
what nerve supplies anterior muscles in upper arm
musculocutaneous nerve
96
what are the three sets of muscles invovled in movement of the arm
1. flexion and extension of elbow
2. pronation and supination of forearm
3. flexion and extension of wrist
97
where do the brachial plexus divisions occur within the body
approx lower neck to axilla region
98
what are the superficial veins of the arm and where are they found (3)
1. cephalic vein = most lateral upper arm
2. Basilic vein = most medial on upper arm
3. Median cubital vein = located going from medial to lateral across anterior elbow hinge. joins basilic and cephalic vein
99
# answer is in order from most lateral to medial
what are the 4 superficial anterior muscles of the forearm?
Pronator Teres
Flexor Carpi radialis
Palmaris Longus
Flexor Carpi Ulnaris
100
what is the common flexor attachment of all 4 flexor muscles of the forearm?
Medial epicondyle of the humerus
101
origin and insertion of pronator teres
origin = medial epicondyle of humerus & proximal ulna
insertion = midshaft of radius, lateral side
102
function of pronator teres (1)
pronation of forearm
103
where does the word teres come from? what does it mean
refers to shape of muscle in cross section - "round"
104
Flexor Carpi radialis origin and insertion
origin = medial epicondyle of humerus
insertion = second and third metacarpal
105
function of flexor carpi radialis (2)
flexes wrist
Wrist abduction
106
how name of FCR helps in function and location (3)
Flexor - flexes
Carpi - inserts onto metacarpals
Radialis - location on radial side
107
Palmaris Longus origin and insertion
origin - medial epicondyle of humerus
insertion - palmar aponeurosis
108
what is the palmar aponeurosis & location
thick dense layer of fibrous tissue
located in the palm of the hand
109
what is the palmar aponeruosis a continuation of?
the antebrachial fascia
110
what is the function of Palmar Longus (1)
Weak wrist flexion
111
presence of PL in population
absent in 10-15% of population!
112
Flexor Carpi Ulnaris origin and insertion
Origin - Medial epicondyle of humerus
Insertion - Pisiform Carpal bone
113
function of Flexor Carpi radialis (2)
wrist flexion
wrist adduction
114
what are the intermidate (level of deepness) anterior muscles of the forearm
Flexor digitorum superficialis (FDS)
115
# 2 heads
origin of the flexor digitorum superficialis
medial epicondyle of humerus
radial head
116
where does the division of the FDS occur, and how many segments does it split into?
Mid forearm
4 segments - one for each finger
117
attachment of FDS:
middle phalanges of each finger
118
function of FDS (2)
wrist flexion
flexion of fingers
119
Brachioradialis origin and insertion
origin - lateral supracondylar ridge of humerus
insertion - styloid process of radius
120
function of the brachioradialis muscle (2)
flex arm at elbow joint
stabiliation of elbow joint when strong grip is required
121
# in order from most deep to most superficial
what are the 3 deep muscles of the anterior forearm?
Pronator quadratus
Flexor pollicus Longus
Flexor Digitorum profundus
122
what is the interosseous membrane? (2)
* fibrous connective tissue structure located between ulna and radius
* spans length of forearm
123
what is the role of the interosseous membrane (2)
* provides stability and support to forearm by maintaining appropriate spatial relationhip betwen radius and ulna
* important for attachments of deep flexor muscles
124
pronator quadratus origin and insertion
origin - anteriomedial aspect of ulna
insertion - anterior surface of radius
125
function of pronator quadratus (1)
pronation of forearm
126
flexor pollicis longus origin and insertion
origin - midshaft of radius
insertion - distal phalanges thumb
127
function of flexor pollicis longus (1)
flexes thumb at interphalangeal joint
128
flexor digitorum profundus origin and insertion
origin - proximal ulna
attachment - distal phalanges of 4 fingers
129
innervation of the 3 deep flexor muscles of the forearm:
PQ - median nerve (AIN)
Flexor pollicis longus - median nerve (AIN)
flexor digitorum profundus - median nerve (AIN) and ulnar nerve
130
# which fingers are innervated by which nerve
flexor digitorum profundus nerve innervation:
AIN nerve - index and midle finger
Ulnar nerve - ring and pinky finger
131
what are the 3 extensor muscles of the forearm
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
132
what is the name of the origin that is shared between the extensor muscles of the forearm?
lateral epicondyle of the humerus
133
extensor carpi radialis & Brevis origin and insertion
origin - lateral epicondyle of the humerus
insertion - 2nd and 3rd metacarpals
134
origin & insertion of the extensor carpi ulnaris
origin - lateral epicondyle of humerus & medial side of ulna
insertion - 5th metacarpal
135
what do all 3 extensor muscles of wrist pass under as they enter the wrist?
* extensor retinaculum
136
what does the extensor retinaculum act as for the extensor muscles of the forearm
a pulley
137
how many muscles produce pronation and what are they?
2:
pronator teres
pronator quadratus
138
how many muscles produce supination and what are they
2:
supinator
biceps
139
origin (3) and insertion of supinator muscle
origin - lateral epicondyle, annular ligament, and supinator crest of ulna
insertion - radius
140
what is the "parallel" muscle of pronator teres
Supinator muscle - due to very similar length, insertion and origin just on opposite sides of arm
141
what branch (nerve) runs through the supinator muscle
radial nerve (PIN)
142
how many muscles produce flexion of the fingers, and what are they?
2
* flexor digitorum profundus
* flexor digitorum superficialis
143
what is the deepest finger flexor
flexor digitorum profundus
144
what type of muscles are the muscles that flex the fingers? (1)
long muscles
145
what are the tendons called that arise from each muscle to attach to the fingers- frmo both finger flexing muscles)
profundus tendon
superficialis tendon
146
passage of profundus tendons (6)
* arise in distal half of forearm
* all bundled together as they enter **carpal tunnel**
* When exiting carpal tunnel, gives rise to 4 muscles known as **lumbricals**
* each finger tendon enters each fingers **flexor tendon sheath**
* emerges etween two halves of superficialis tendons
* inserts onto base of **distal phalanges**
147
passage of the superficialis tendons: (6)
* arise in distal half of forearm
* all bundled together as they enter **carpal tunnel**
* each finger tendon enters each fingers **flexor tendon sheath**
* splits into two halves after exiting flexor tendon sheath
* pass around profundus tendon
* reunite deep to profundus tendon and insert into middle phalanges
148
action of flexor digitorum profundus muscle: (2)
flex both IP and MP joints
149
action of flexor digitorum superficialis muscle (2)
flex proximal IP joint and MP joint
150
what is the IP joint? and what are the two types
the interphalangeal joint between the phalanges of the finger
the two types:
1. proximal - between proximal and middle phalanges
2. distal - between middle and distal phalanges
151
what is the MP joint?
joint between the etacarpal bone and the proximal phalanges
152
# superior, medial, and lateral
what are the 3 boundaries of the cubital fossa
superior - imaginary line connecting medial and lateral epicondyles of humerus
medial - formed by pronator teres
lateral boundary - brachioradialis muscle
153
what is the floor and roof of the cubital fossa
roof - fascia
floor - muscles
154
contents of the cubital fossa (7)
* brachial artery - bifurcates here into -->
* radial and ulnar arteries
* medain nerve
* tendons of biceps brachii
* cephalic and basillic vein
155
how can the ulnar nerve be compressed within the cubital fossa? (2)
* pinched against medial epicondyle as it passes through **cubital tunnel**
* can be compressed by two heads of flexor carpi radiallis muscle
156
which muscles of the anterior forearm does the median nerve innervate? (7)
1. Pronator teres
2. Flexor carpi radialiis
3. Palmaris Longus
4. Flexor Digitorum Superficialis
5. Flexor Digitorum Profundus (lateral)
6. Pollicis Longus
7. Pronator Quadratus
157
what muscles of the anterior forearm are innervated by the ulnar nerve? (2)
1. Flexor Carpi Ulnaris
2. Flexor Digitorum Profundus (medial)
158
Artery names from subclavian artery at base of neck (4)
Axillary artery --> Brachial artery --> radial & ulnar artery
159
Deep veins of the arm (4)
Axillary vein
Brachial veins
Radial & ulnar veins
160
what is the palmer view of the hand
a view of the hand where the palm is seen
161
what are the two main eminences of the hand?
Hypothenar eminence
Thenar eminence
162
why are the two eminences prominent on the palmar view of the hand?
due to the many muscles located within these areas
163
ulnar nerve passage in the hand: (3)
* passes down ulnar side of wrist
* divides into digital branches within hypothenar eminence
* 2 branches for pinky, one for medial side of ring finger
164
passage of the median nerve in the hand: (2)
* passes into wrist through crpal tunnel
* divides into common digital nerves for fingers excluding pinky and including thumb
* splits further into proper digital nerves
165
how many proper digital nerve branches does the median nerve give off?
7
* 1 for ring finger, 2 for each other digit (including thumb)
166
where does the radial nerve innervate on the palmer side of the hand? (1)
* base of thumb on palmer side
167
what arteries supply the hand with blood? (2)
ulnar and radial artery
168
What is the superficial palmer arch? (3)
* an "arch" shaped vessel in the palm of the hand
* formed by the superficial branches of both ulnar and radial arteries anastomosing
* in palm of hand
169
what artery is the main contributer of the superficial palmer arch?
ulnar artery
170
What is the deep palmer arch? (3)
* an "arch" shaped vessel in the palm of the hand
* formed by the deep branches of both ulnar and radial arteries anastomosing
* in palm of hand
171
what is the main contributer of the deep palmer arch?
radial artery
172
what is the palmer aponeurosis? (3)
* a connective tissue structure that sits in the middle of the palm
* superficially to muscles
* provides attachment for other structures
173
which **group** of muscles form the thenar eminence?
thenar muscles
174
which **group** of muscles form the hypothenar eminence?
hypothenar muscles
175
what is the difference in location between intrinsic and extrinsic muscles of the hand?
intrinsic = found in hand only
extrinsic = originate from forearm/ outside hand
176
what are the 4 groups of intrinsic muscles in the hand?
1. interosseous muscles
2. lumbricals
3. short muscles of the thumb
4. short muscles of the little finger
177
how many interosseous muscles are there? how to remember this
7
* one for each side of fingers, put only one for lateral side of pinky
178
what are the two groups of interosseous muscles?
* 4 dorsal interossei
* 3 palmer interossei
179
where does each interossei arise? (2)
* shaft of own fingers metacarpal & its neighbours
180
# long & short
insertion of the interossesi: (2)
long part (tendon)- distal phalanges
short part (tendon) - proximal phalanges
181
what is the extensor mechanism of the finger? (3)
* a fibrous structure
* located on dorsal side of each finger
* extending from the metacarpophalangeal joint to distal phalanges
182
what is the function of the extensor mechanism of the fingers? (4)
* extension of fingers
* stabilization of Metacarpophalangeal joint
* attachment for intrinsic muscles
* prevents 'bowstringing' of extensor tendons
183
role of the interosseous muscles: together (2)and seperately (2)
* together - flex fingers at MP joint & extend both IP joints
* seperately - produce ulna or radial deviation
184
how does the fine movement of fingers occur? (4)
due to complex interactions between interossei, lumbricals, and long flexors and extensors
185
# location, size, heads, arteries passing through, and function
the first dorsal interosseous muscle:
* located between index and thumb
* very large relative
* 2 heads - arising from 1st and 2nd metcarpals
* radial artery passes between two heads
* powerful radiation of index finger
186
what are the pair of muscles involved in the "key pinch" action (holding a key action)
1. first dorsal interosseous muscls
2. adductor pollicis
187
how many lumbrical muscles are there?
4 - one for each finger
188
where does each lumbrical muscle arise from?
the side of one or both adjoining digitorum profundus tendons
189
insertion of each lumbrical
Radial side of extensor mechanism
190
where is the insertion of the lumbrical and long part of interosseous tendon relative to each other on the extensor mechanism?
lumbrical insertion is just distal to long part of interosseous tendon
191
action of the lumbricals (2)
extends IP joint
radial deviation of MP joint
192
how many short (intrinsic) muscles of the thumb are there?
4
193
which of the short muscles of the thumb lies seperate to the rest?
Adductor pollicis
194
adductor pollicis origin: (2)
two heads:
* transverse head - third metacarpal
* oblique head - ligaments at base of carpal tunnel
195
insertion of adducotr pollicis (2)
* ulnar sesamoid bone
* base of proximal phalanges of thumb
196
function of adductor pollicis (1)
adduction at carpometacarpal joint
197
# anatomical feature of the palm
what do the 3 other short muscles of the thumb make up?
thenar eminence
198
what are the 3 short muscles of the thumb that are lose together also known as?
the thenar muscles
199
what 3 muscles make up the group of thenar muscles?
1. flexor pollicis brevis
2. adbuctor pollicis brevis
3. opponens pollicis (deepest)
200
flexor pollicis brevis origin (2) and insertion (1)
origin:
* flexor retinaclulum
* trapezoid
insertion:
* base of proximal phalanges of thumb
201
function of flexor pollicis brevis?
(1)
flexes thumb at metacarpophalangeal joint
202
origin (2) and insertion (1) of abductor pollicis Brevis
origin:
* trapezium
* flexor retinaculum
Insertion:
* base of proximal phalanges of thumb
203
function of abductor pollicis Brevis (1)
abducts thumb away from palm (moves thumb away from other fingers)
204
Opponens pollicis origin (2) and insertion (1)
origin:
* trapezium
* flexor retinaculum
Insertion:
* radial side of first metacarpal
205
function of Opponens pollicis
brings thumb in contact with tip of other fingers
206
(2)functions of the thenar muscles together: what the actions are (2) are what it actually looks like (3)
abduction and flexion at carpometacarpal joint - brings thumb away from hand and across the palm - rotating it medially
207
what bulge on the palm that is an anatomical feautre of the hand do the three short muscles of the finger together make up?
hypothenar eminence
208
how many muscles make up the hypothenar eminence?
3
209
what are the three short muscles of the little finger?
1. abductor digiti minimi
2. flexor digiti minimi
3. Opponens digiti minimi - deep
210
abducotr digit minimi origin (1) and insertion (2)
origin:
* pisiform bone
insertion:
* base of proximal phalanges
* partly also in extensor mechanism
211
# the same as another intrinsic hand muscle
function of abductor digiti minimi (1)
ulna deviation
212
flexor digiti minimi origin (2) and insertion (1)
origin:
* hammate bone
* flexor retinaculum
insertion:
* proximal phalanges
213
function of flexor digiti minimi (1)
helps interosseous muscles in flexing MP joint
214
Opponens digiti minimi origin (1) and insertion (1)
origin - hook of hammate bone
insertion - ulna side of 5th metacarpal
215
function of Opponens digit minimi (1)
flexor of 5th metacarpal at carpometacarpal joint
216
what nerve and artery passes underneath the flexor and opponens uscle of the hypothenar group?
ulnar nerve
ulnar artery
217
passage of the ulnar artery in the forearm: (6)
* passes beneath pronator teres
* gives off **common interosseous artery**
* passes benath two heads of flexor digitorum superficialis
* runs down forearm between flexor digitorum superficialis and profundus
* in distal forearm, emerges with ulnar nerve
* passes through tunnel at side of flexor retinaculum
218
passage of radial artery in forearm: (5)
* runs down forearm deep to brachioradialis
* lies on top of pronator teres
* emerges in distal forearm from brachioradialis
* lies superficially between boarder of radius and tendon of flexor carpi radialis
* gives off superficial and deep branches at wrist
219
median nerve forearm passage: (5)
* travels between two heads of pronator teres
* then passes through 2 heads of flexor digitorum superficialis
* travels down forearm between flexor digitorum superficialis and profundus
* emerges at wrist at radial side of superficialis tendons
* passes through carpal tunnel
220
what two tendons cross over the median nerve at the wrist joint?
palmaris longus
flexor carpi radialis
221
median nerve motor innervation in hand:
* thenar muscles
222
sensory nerve passage of median nerve in hand (3)
* 3 common digital nerves
* split off into 2 palmar digitital nerves for: thumb, index and middle finger.
* only 1 for lateral half of ring finger
223
sensory distribution of median nerve in palmer hand: (5)
* thumb
* index finger
* middle finger
* lateral half of ring finger
* lateral half of palm from lateral half of ring finger
224
ulnar nerve passage in the forearm: (5)
* passes between two heads of flexor carpi ulnaris
* runs down flexor carpi ulnaris and flexor digitorum superficialis
* halfway down forearm, gives off dorsal sensory branch
* at wrist, runs along radial side of flexor carpi ulnaris
* passes through side tunnel in edge of flexor retinaculum
225
# is a branch of the ulnar nerve
where does the dorsal sensory branch travel to?
back/ dorsal side of hand
226
what also passes through side tunnel in edge of flexor retinaculum as well as ulnar nerve? (1)
ulnar artery
227
ulnar nerve passage in hand: (5)
divides into superficial and deep branches
superficial:
* divides into palmer digitial nerves for little finger and ulna side of ring finger
deep:
* passes between hypothenar muscles
* runs across palm in front of interossei
* passes inbetween two heads of adductor pollicis
228
what are the sensory and motor branches of the ulnar nerve in the hand? (2)
sensory = superficial
motor = deep
229
why does the deep branch of the ulnar nerve pass inbetween two heads of adductor pollicis (1)
to reach most radial of interossei to innervate it
230
sensory innervation of ulnar nerve in hand (both sides) (2)
* imaginary line stretching down palm from medial half of ring finger
* same for dorsal side
231
motor innervation of ulnar nerve in the hand: (4)
1. hypothenar muscles
2. all interossei
3. adductor pollicis
4. ulnar two lumbrical muscles
232
what 2 long muscles are involves in finger flexion?
1. flexor digitorum profundus
2. flexor digitorum superficialis
233
flexor digitorum profundus origin: (2)
* anterior and medial surface of ulna
* interosseous membrane
234
# 2 heads
flexor digitorum superficialis origin: (1 & 2)
radial head:
* radius
humeroulnar head;
* part of **common flexor tendon** from medial epicondyle of humerus
* also from adjoining ulna
235
why is there a gap between the two heads of flexor digitorum superficialis?
median nerve and ulnar artery both pass through
236
what does lumbricals mean?
worm-like
237
what strutures pass through the carpal tunnel? (4)
* flexor digitorum profundus
* flexor digitorum superficialis
* median nerve
* flexor pollicis longus
238
what is the carpal tunnel surrounded by?
the flexor retinaculum
239
what is the flexor retinaculum also known as?
the transverse carpal ligament
240
what is the flexor retinaculum? (3)
* a strong fibrous band
* surrounds the carpal tunnel
* forms a flexible but strong roof over carpal tunnel
241
function of the flexor retinaculum (2)
* provides protection for structures passing through carpal tunnel
* prevents bowstringing of the hand tendons
242
what is "bowstringing"?
the excessive movement or displacement of tendons away from their normal position during flexion or extension
243
how does the flexor retinaculum prevent bowstringing?
* supportive roof & floor around carpal tunnel, preventing excessive movement of the tendons in flexion an extension
244
how many rotator cuff muscles are there and what are they
4:
* subscapularis
* supraspinatus
* infraspinatus
* teres minor
245
what is the main function of the rotator cuf muscles as a whole (3)
* provide stability to the glenohumeral joint
* by compressing and depressing it
* against the glenoid fossa
246
what muscles do the rotator cuff muscles lie beneath (4)
1. pectoralis major
2. deltoid
3. trapezius
4. latissimus dorsi
247
where is the glenoid fossa of the scapula? (3)
* the shallow groove
* where the humeral head sits
* within the shoulder joint
248
approximately how much of the humeral head sits within the glenoid fossa?
1/3
249
location of the supraspinatus: (2)
* sits in s**upraspinous fossa**
* above spine of scapula
250
origin and insertion of supraspinatus
origin - supraspinous fossa
insertion - greater tuberosity of humerus - superior facet
251
path of supraspinatous (1)
passes under the acromion
252
what is the acromion a part of? and its location
the scapula:
* situated at top of scapula
253
what does the acromion articulate with and what does it form?
the clavicle
forms the acromioclavicular joint
254
function of the supraspinatus (1)
abduction of the humerus
255
innervation of the supraspinatus
suprascapular nerve
256
where does the suprascapular nerve arise from?
superior trunk of the brachial plexus
257
location of the infraspinatus (2)
* below spine of scapula
* in infraspinous fossa
258
origin and insertion of infraspinatus
origin - infraspinous fossa
insertion - greater tuberosity of humerus - middle facet
259
function of the infraspinatus (1)
lateral rotation of the humerus
260
innervation of the infraspinatus
suprascapular nerve
261
Teres minor location (2)
* just inferior to infraspinatus
* lateral boarder of scapula
262
origin and insertion of the teres minor:
origin - lateral boarder of scapula
insertion - greater tuberosity of humerus - inferior facet
263
function of teres minor (1)
lateral rotation of humerus
264
innervation of the teres minor
axillary nerve
265
origin and insertion of the subscapularis
origin - subscapular fossa
insertion - lesser tuberosity of the humerus
266
what is the subscapular fossa? (2)
* a depression in the scapula
* occupying almost all anterior part of scapula
267
what is the strongest muscle of the rotator cuff muscles and how much "cuff strength" does it have?
subscapularis - 50%
268
what muscles make up the thenar eminence? (3)
abductor pollicis brevis
flexor pollicis brevis
opponens pollicis
269
function of the subscapularis (1)
medial rotation of the humerus
270
innervation of the subscapularis (2)
subscapular nerve - upper & lower
271
where do the upper and lower subscapular nerves arise from?
posterior cord of the brachial plexus
272
what is the most commonly injured muscle of the rotator cuff muscles? (1) why? (2)
supraspinatous:
* upon elevation of arm, space between acromion and supraspinatus tendon narrows
* therefore, this tendon can get easily pinched, inflammed and torn
273
what type of action is usually associated with rotator cuff injury?
overhead arm action
274
what is the most common rotator cuff related injury? & what is this
sub-acromial impingement syndrome:
* relates to conditions associated with sub acromial space
275
what are the 2 most common pathologies within sub-acromial impingement syndrome, and what are they due to
supraspinatus tendonitis - due to overuse
subacromial bursitis - inflammation of subacromial bursa
276
what is a rare pathology within sub-acromial impingement syndrome? and definition (2)
Bony spurs - small bony spurs (spikes) projecting off acromion, can pinch bursa/tendon below
277
main symptom of sub-acromial impingement syndrome? why is this so?
pain between 60-120 degrees of arm - it is where sub acromial space is most narrow
278
why do some rotator cuff injuries effecting just one muscle require rehabilitation of the whole rotator cuff? (2)
* if all muscles are strengthened, the humeral head will be better depressed and compressed
* so more clearance between humerus and acromion during arm movement
279
what are the muscles in the posterior upper arm?
triceps
280
how many heads does the triceps have? their names
3:
lateral
medial
long
281
what does the long head of the triceps do that is unique compared to the other heads? (1)
attaches onto the scapula, not humerus
282
what do all three heads of the triceps attach onto? why?
olecranon process of the ulna
they become one tendon more distally
283
origin and insertion of lateral head of triceps
origin - superior half of posterior humerus, superior to radial groove
insertion - olecranon process of ulna
284
origin of medial head of triceps:
lower half of posterior humerus - inferior to radial groove
285
origin of long head of triceps (2)
infraglenoid tubercle of the scapula
286
Teres major origin and insertion:
origin - lower lateral boarder of scapula
insertion - medial lip of bicipital groove
287
Teres major function (3)
* Shoulder extension (arm backwards behind body)
* adductor of humerus
* internal humerus rotation
288
relationship between position of teres major and long head of triceps (1)
fibres of teres major are on the anterior side of the long head of the triceps
289
what important branches of the axillary artery is given off within the teres major-long head cross over region? (2)
1. posterior circumflex humeral artery
2. deep brachial artery - just inferior
290
what important anatomical feature occurs when axillary artery crosses teres major?
axillary artery becomes brachial artery
291
what is the posterior-circumflex humeral artery accompanied by in its passage?
axillary nerve
292
path of the posterior-circumflex humeral artery and axillary nerve at teres major: (1)
both wrap around surgical neck of humerus
293
path of the deep brachial artery:(3)
* exits through **triangular space**
* wraps around middle third of humerus
* travels through **spiral groove** of humerus
294
what is the deep brachial artery accompanied by on its path:
radial nerve
295
what sort of fracture of the humerus is most likely to cause radial nerve and brachial artery damage?
fracture of the **mid-shaft** of the humerus
296
innervation of the triceps heads:
radial nerve - all three heads
297
# comes in pairs
what are the 6 scapula movements?
elevation & depression
protraction & retraction
upward & downward rotation
298
what are the superficial back & shoulder muscles? (3)
1. deltoid
2. trapezius
3. latissimus dorsi
299
what are the 3 muscles deep to the trapezius involved in scapula movement?
## Footnote
in order from superior to inferior for extra points!
1. levator scapulae
2. Rhomboid minor
3. Rhomboid major
300
what are the 3 muscles deep to the trapezius innervated by? (3,1,1)
levator scapulae - dorsal scapular nerve, cervical nerves C3 and C4
rhomboid minor - dorsal scapular nerve
rhomboid major - dorsal scapular nerve
301
Teres major vs minor attachments and hence which does which rotation of arm
Teres major - medial lip of bicipital groove, medial rotation of arm
Teres minor - greater tubercle, lateral rotation of arm
302
what part of the scapular do the subscapular nerves and vessels pass through?
suprascapular notch
303
which vessels and veins pass through the suprascapular notch? (3)
suprascapular artery
suprascapular vein
suprascapular nerve
304
# ligament
what covers the suprascapular notch
superior transverse scapular ligament
305
where are the quadrangular and triangular space in relation to each other?
quadrangular is slightly superior to triangular space - almost adjacent
306
boarders of the triangular space: (3)
superior - teres minor
inferior - teres major
lateral - long head of triceps
307
# most lateral to medial for extra point!
what is the location of the posterior forearm muscles? (7)
* Brachioradialis
* Extensor carpi radialis longus
* Extensor carpi radialis Brevis
* Extensor indicis proprius
* Extensor digitorum Communis
* Extensor Digiti Minimi
* Extensor Carpi Ulnaris
308
what is the innervation of the posterior muscles of the forearm?
Radial nerve supplies all (or a branch)
309
which extensor muscle of the posterior forearm does not arise from the lateral epicondyle & supracondylar ridge region?
extensor indicis proprius
310
where does the extensor indicis proprius arise? (2)
* distal third of posterior ulna
* interosseous membrane
311
location of the lateral epicondyle and supracondylar ridge in relation to each other (1)
supracondylar ridge is just superior to lateral epicondyle
312
what is the clinical significance of the common attachment region of the extensor forearm muscles? and name (2)
often inflamed and painful - tennis elbow
313
what is the similar condition of inflammation of medial epicondyle flexor muscles of the forearm? (1)
golfers elbow
314
which muscle of the posterior muscles of the forearm is a clear outlier to the rest (1) and why? (2)
brachioradialis - involved in elbow joint flexion, & does not cross wrist
315
what muscle lies immediately adjacent to the brachioradialis?
extensor carpi radialis longus
316
what are the primary wrist extensors? (3)
* extensor carpi radialis longus
* extensor carpi radialis brevis
* extensor carpi ulnaris
317
extensor carpi radialis longus insertion: (1)
2nd metacarpal
318
extensor carpi radialis Brevis insertion (1)
3rd metacarpal
319
extensor carpi ulnaris insertion (1)
5th metacarpal (base)
320
what are the 3 long finger extensor muscles?
1. extensor digitorum communis
2. extensor digiti minimi
3. extensor indicis proprius
321
extensor digitorum communis insertion (1)
distal phalanges of all digits (not thumb)
322
path of extensor tendons: (7)
1. 4 tendons emerge in distal forearm
2. pass together under extensor retinaculum
3. extensor tendons fan out after exiting extensor retinaculum
4. have connecting fibres just before MP join
5. attaches to MP joint
6. Gives rise to extensor hood
7. Divides into three parts for each phalanges
323
function of extensor digitorum communis (3)
extension of fingers at all 3 joints:
* MP - main effect
* 2 IP joints
324
extensor indicis proprius insertion (1)
distal phalanges of index finger
325
extensor digiti minimi insertion (1)
distal phalanges of little finger
326
which fingers have two extensor muscles compared to the rest that have one? (2)
index and pinky
327
what hand movement illustrates how some fingers have more extensor muscles than others? (3)
spider man "thwip" - easy to extend index and pinky independently, but is not as easy to do middle and ring finger
328
where is the extensor indicis proprius (EIP) tendon seen in relation to the extensor digitorum (EDC) index finger tendon? (1)
EIP is seen more medial to central hand
329
where is the extensor digiti minimi (EDM) tendon relative to the extensor digitorum communis (EDC) tendon? (1)
EDM is more lateral to central hand
330
how are all extensor tendons of the forearm and fingers kept in place? (1)
extensor retinaculum
331
what is the extensor retinaculum? (2)
* a fibrous tissues
* located over dorsum of wrist joint
332
what muscle do the extensor muscles of the thumb lie immediately deep too?
extensor digitorum communis
333
what are the three extensor muscles of the thumb?
1. abductor pollicis longus
2. extensor pollicis brevis
3. extensor pollicis longus
334
abductor pollicis longus origin (3)
* posterior surface of ulna & radius
* interosseous membrane
335
insertion of adductor pollicis longus (1)
1st metacarpal
336
function of adductor pollicis longus: (1)
adduction of thumb
337
what joint does abductor pollicis longus act on?
carpometacarpal joint
338
extensor pollicis brevis origin (2)
* posterior radius
* interosseous membrane
339
insertion of extensor pollicis brevis (1)
proximal phalanges of thumb
340
what is the function of extensor pollicis Brevis? (1)
extension of proximal phalanges of thumb
341
what joints does the EPB act on? (2)
1. carpometacarpal joint
2. metacarpophalangeal joint
342
extensor pollicis longus origin (2)
* posterior ulna
* interosseous membrane
343
insertion of extensor pollicis longus (1)
distal phalanges of thumb
344
what joints does the EPL act on? (3)
1. carpometacarpal joint
2. metacarpophalangeal joint
3. interphalangeal joint
345
what is the location of the 3 extensor muscles of the thumb most ulna to radial?
* extensor pollicis longus
* extensor pollicis brevis
* abductor pollicis longus
346
what two extensor muscles of the thumb travel together
* abductor pollicis longus
* extensor pollicis brevis
347
origin of thumb extensor muscles on forearm in order of most proximal to distal (3)
* abductor pollicis longus
* extensor pollicis longus
* extensor pollicis brevis
348
which artery travels between extensor pollicis brevis and extensor pollicis longus?
radial artery
349
what space is formed by the extensor pollicis longus and the tendons of EPB and APL?
the anatomical snuff box
350
what does the flexor carpi ulnaris actually attach onto? (1)
pisiform bone
351
how is the flexor carpi ulnaris pull transmitted to the 5th metacarpal? (3)
via two ligaments:
* Pisohamate ligament - transmits pull from pisiform to hamate
* Pisometacarpal ligament - transmits pull from pisiform to 5th metacarpal
352
what are the 3 functional groups of the posterior forearm muscles?
* wrist action muscles
* digits acting muscles
* thumb acting muscles
353
which muscles act at the wrist joint in the posterior forearm? (3)
1. extensor carpi ulnaris
2. extensor carpi radialis longus
3. extensor carpi radialis brevis
354
what are the muscles in the deep layer of the posterior forearm? (5)
* supinator
* abductor pollicis longus
* extensor pollicis brevis
* extensor pollicis longus
* extensor indicis
355
role of palmer interosseous muscles vs dorsal interosseous muscles:
Palmer - adduction of digits
Dorsal - abduction of digits
## Footnote
way to remember: PAD and DAB
356
what are dermatomes? (1)
specific areas of skin supplied by a single spinal nerve or segment
357
what are myotomes (1)
specific groups of muscles primarily innervated by a single spinal nerve or segment
358
teres major origin and insertion:
* origin - lateral scapula
* insertion - anterior humerus
359
subscapularis origin and insertion:
* origin - subscapular fossa
* insertion - anterior humerus
360
how does the lattissimus dorsi make up the posterior boundary of the axilla? (1)
* terminal part attaches to anterior humerus
361
what is the blood supply to the deltoid? (3)
* deltoid branch of the thoraco-acromial artery
* anterior and posterior circumflex artery
* subscapular artery
361
origin and insertion of latissimus dorsi:
origin:
* T7 to posterior iliac spine
insertion:
* bicipital groove
362
function of the latissimus dorsi (2)
* adductor of humerus
* depressor of scapula
