Upper Limb Anatomy Flashcards
1
Q
What shape is the axilla?
A
Pyramidal shape
2
Q
What are the borders of the axilla?
A
Has a
Base
Apex
4 walls
3
Q
What makes up the anterior wall of the axilla?
A
Pectoralis major
Pectoralis minor
4
Q
Under which joint does the axilla lie under?
A
Shoulder joint/ glenohumeral joint
5
Q
What makes up the posterior border of the axilla?
A
Subscapularis
Teres minor
Latissimus dorsi
6
Q
What makes up the medial wall of the axilla?
A
Serratus anterior
and
Thoracic wall
7
Q
What makes up the lateral border of the axilla?
A
Intertubercular groove of humerus
8
Q
What are the contents of the axilla?
A
Axillary artery Axillary vein Brachial plexus Biceps brachii and coracobrachialis Axillary lymph nodes
9
Q
The axillary artery is a continuation of which artery?
A
Subclavian artery
10
Q
At which anatomical point does the axillary artery begin?
A
Lateral edge of 1st rib
11
Q
At which anatomical point does the axillary artery become the brachial artery?
A
Lower border of teres major muscle
12
Q
The axillary artery continues as?
A
Brachial artery
13
Q
What does the brachial artery bifurcate into?
A
Radial artery
Ulnar artery
14
Q
Where does the brachial artery bifurcate?
A
As it crosses the cubital fossa
15
Q
Which plexus innervates the upper limb?
A
Brachial plexus
16
Q
Which nerve roots form the brachial plexus?
A
Ventral rami of C5,6,7,8 and T1
17
Q
Which nerve roots form the upper/superior trunk?
A
C5/6
18
Q
Which nerve roots form the middle trunk?
A
C7
19
Q
Which roots form the lower/inferior trunk?
A
C8 and T1
20
Q
What is Erb’s Palsy?
A
Injury to upper trunk (C5/6)
21
Q
Which palsy is associated with waiter tip
A
Erbs palsy
22
Q
Describe waiters tip
A
Medially rotates upper limb with wrist flexed
23
Q
How does Erb’s palsy commonly occur?
A
Birth trauma
Dystocia
24
Q
Which segmental roots of the brachial plexus contribute to the lower trunk of the brachial plexus
A
C8 and T1
25
What is Klumpke's Palsy
Injury to the lower trunk
26
How are the cords of the brachial plexus named
Named for their position in relation to the axillary artery
27
What are the 3 cords of the brachial plexus
Lateral
Medial
Posterior cords
28
What are the major nerve branches of the brachial plexus
```
Musculocutaneous nerve
Axillary nerve
Median Nerve
Radial nerve
Ulnar nerve
```
29
Name the major arteries of the upper limb
```
Subclavian artery
Axillary artery
Brachial artery
Radial artery
Ulnar artery
```
30
What are the 2 palmar arches of the hand?
Superficial palmar arch
| Deep palmar arch
31
What are the main superficial veins of the upper limb?
Cephalic vein
Basilic vein
Median Cubital vein
32
Which vein arises at the lateral end of the dorsal venous arch
Cephalic vein
33
Which vein arises from the medial end of the dorsal venous arch
Basilic vein
34
Why do superficial veins assume important in medical practice?
Because they are commonly used for intravenous injections for transfusions and for withdrawing bloods
35
From which vein to which vein does the median cubital vein shunt blood?
From cephalic to basilic vein
36
What is a dermatome?
Are of skin supplied by one spinal segment
37
Which dermatome lies over the nipples?
T4
38
Which dermatome lies over the umbilicus
T10
39
Which dermatome supplies the thumb?
C6
40
Which dermatome supplies the index and middle finger?
C7
41
Which dermatome supplies the ring and little finger?
C8
42
Where do lymphatic vessels from the upper limb drain into?
Axillary lymph nodes
43
What are the 4-5 distinct groups of the axillary lymph nodes/
```
Apical group
Central group
Lateral group
Anterior/pectoral group
Posterior/subscapular group
```
44
When is enlargement of the axillary lymph nodes common
During malignancy
45
Which group of LN would drain the lateral part of the breast?
Axillary lymph nodes
46
Which group of LN would drain the medial breast close to sternum?
Internal mammary/thoracic LN
47
Infection around the umbilicus can spread to both superficial inguinal and axillary LN why?
Above it drained by axillary
| Below it drains to superficial inguinal LN
48
What is the pectoral girdle?
Set of bones which connect the upper limb to the axial skeleton on both sides
49
What are the 2 ends of the clavicle called?
Sternal end
| Acromial end
50
Which end of the clavicle is medial?
Sternal end
51
Which end of the clavicle is lateral
Acromial end
52
Which part of the clavicle is the weakest?
Middle 1/3
53
What type of joint is the acromioclaviclar joint?
Synovial plane
54
What type of joint is the sternoclavicular joint?
Synovial saddle
55
What does the acromioclaviclar joint connect?
Lateral clavicle (acromial end)
And
Acromion of scapula
56
What does the sternoclavicular joint connect?
Sternal/medial clavicle
| Manubrium of sternum
57
Which muscles cause elevation of the scapula?
Upper trapezius
Levator scapulae
Rhomboids
58
Which muscles cause depression of the scapular
Lower Trapezius
Serratus anterior
Pectoralis minor
59
Which muscles cause protraction of the scapula?
Serratus anterior
60
Which muscle causes retraction of the scapula?
Middle trapezius fibres
| Rhomboid muscles
61
Which muscle causes lateral (upward rotation) of the scapula
Upper and middle trapezius fibres
62
Which muscles cause medial (downward) rotation of the scapula?
Rhomboids
Pectoralis minor
Levator scapulae
With help from gravity
63
What type of joint is the glenohumeral joint?
Ball and socket
64
Is the rhomboid major muscle superior or inferior to rhomboid minor muscle
Inferior
65
Which is the most superficial back muscle?
Trapezius
66
Innervation of trapezius
Accessory nerve
| Cranial nerve 11
67
How do you test the trapezius muscle
Ask the patient to shrug their shoulders
68
What do upper trapezius fibres do to the scapula
Elevate it
69
What do middle fibres of the trapezius do to the scapula?
Retract it
70
What do lower fibres of the trapezius muscle do to the scapula?
Pull it inferiorly
71
What is the ball of the glenohumeral joint?
Head of the humerus
72
What forms the socket of the glenohumeral joint?
The glenoid cavity
73
The rim of cartilage surrounding the glenohumeral socket is the
Glenoid labrum
74
What is the function of the glenoid labrum?
To deepen the socket
75
What nerve is injured in winging of the scapula?
Long thoracic nerve
76
During which procedure is the long thoracic nerve commonly injured
Axillary nerve clearance in breast surgery
77
Which aspect of the glenohumeral joint does the glenohumeral ligaments strengthen?
Anterior aspect
78
What does the coraco-acromial ligament prevent
Superior displacement
79
What does the coracohumeral ligament strengthen?
Superior aspect of joint capsule
80
Which part of the shoulder joint capsule is weakest as is not protected by muscles or ligaments
Anterior
| Inferior
81
Name the 4 rotator cuff muscles
Subscapularis
Supraspinatus
Infraspinatus
Teres minor
82
Where do the 4 rotator cuff muscles extend from to?
Scapula to humerus
83
What is the most important role of the 4 rotator cuff muscles?
To pull the humeral head into the glenoid fossa
84
Which 2 intrinsic shoulder muscles extend from the scapula and trunk to the humerus
Deltoid
| Teres major
85
What is the action of anterior fibres of the deltoid muscle?
Flexion and medial rotation of arm
86
What is the action of middle fibres of the deltoid muscle?
Abduction of arm
87
Which muscles does the middle deltoid take over from in abduction of the arm
Takes over from supraspinatus which abducts first 15 degrees
88
What is the action of the posterior deltoid fibres?
Extension and lateral rotation of arm
89
What is the nerve supply to the deltoid muscle
Axillary nerve
90
In what common injury is the axillary nerve commonly trapped
Shoulder dislocation
| Fracture of surgical neck of humerus
91
Where would you test for sensation loss in axillary nerve injury?
Regimental badge area
92
Where do the fibres of the pectoralis major originate from
Medical third of clavicle
Sternum
Ribs
93
What is the action of the pectoralis major on the shoulder
Flexion
| Adduction
94
Which vein below the clavicle is used for placement of central lines
Subclavian vein
95
What is the action of the serratus anterior on the scapulae
Protraction
96
What is the nerve supple of the serratus anterior?
Long thoracic nerve
97
What are the actions of the teres major on the shoulder joint
Adduction
| Medial rotation
98
What are the actions of the actions of the latissimus dorsi on the shoulder?
Extension
Medial rotation
Adduction
99
Which muscle causes flexion of the shoulder joint
Pectoralis major
Anterior deltoid
Coracobrachialis
Biceps Brachii
100
Which muscles cause extension of the shoulder joint?
Posterior deltoid
Teres major
Latissius dorsi
101
Which muscles cause adduction of the shoulder joint?
Pectoralis major
Latissimus dorsi
Theres major
Coracobrachialis
102
Which muscles cause abduction of the shoulder joint?
0-15 degrees supraspinatus
15-90 degrees- middle deltoid fibres
Past 90 degrees the scapula needs rotated
103
Which muscles cause internal/medial rotation of the shoulder
```
Subscapularis
Lattisimus dorsi
Pectoralis major
Teres major
Anterior deltoid
```
104
Which muscles cause lateral or external rotation of the shoulder joint?
Teres minor
| Infraspinatus
105
What are the 3 main muscles in the anterior compartment of the arm
Biceps brachii
Coracobrachialis
Brachialis
106
How many heads does the bicep muscle have?
2
107
Which is the most anterior muscle of the anterior arm
Biceps brachii
108
Where does the biceps brachii insert into distally?
Tuberosity of the radius
109
What are the 2 heads of the biceps brachii muscles?
Long head
| Short head
110
Which head of the biceps brachiii arises from the coracoid process?
Short head
111
Which other muscle arises at the coracoid process?
Coracobrachialis
112
Which head of the biceps brachii arises from the supraglenoid tubercle?
Long head
113
What is the action of the biceps brachii on the shoulder and elbow joint?
Flexion at both joint
114
What is the action of the biceps on the superior radio ulnar joint
Powerful supinator
115
What is the nerve supply to the biceps?
Musculocutaneous nerve
116
Which segmental fibres mainly innervate the biceps brachii muscle
C5,6,7
117
From which cord of the brachial plexus does the musculocutaneous nerve arise from?
Lateral cord
118
What is the action of the coracobrachialis on the shoulder joint?
Flexion arm at shoulder
| Weak adduction
119
What is the nerve supply of the coracobrachialis?
Musculocutaneous nerve
120
What are the BBC muscles?
Biceps Brachii
Brachialis
Coracobrachialis
121
What is the innervation of the BBC muscles?
Musculocutaneous nerve
122
Where does the brachialis muscle insert?
To the coronoid process of the ulna
123
What is the main action of the brachialis on the elbow joint?
Flexion at elbow
124
Which nerve supplies the brachialis?
Musculocutaneous nerve
125
What is the main nerve of the anterior compartment of the arm?
Musculocutaneous nerve
126
Which muscle does the musculocutaneous nerve pierce?
The coracobrachialis
127
What does the musculocutaneous nerve continue as?
Lateral cutaneous nerve of forearm
128
Why is the musculocutaneous nerve called the musculocutaneous nerve
Cause it supplies muscle
| And also has cutaneous sensation functions
129
From which part of the forearm does the musculocutaneous nerve carry cutaneous sensations?
Lateral aspect of the forearm
130
What is the brachial artery a continuation of?
The axillary artery
131
Where does the brachial artery end?
At the cubital fossa
132
What does the brachial artery bifurcate into?
The radial and ulnar artery
133
What is the profunda brachii artery a branch of?
Brachial artery
134
Which artery is commonly auscultated to measure blood pressure?
Brachial artery
135
From which cords does the median nerve arise from?
Lateral cord
AND
Medial Cord
136
Does the median nerve give any branches in the axillary or upper arm?
No
137
What are the roots of the median nerve
C6-T1
138
How does the median nerve travel in relation to the brachial artery?
Initially along the lateral side of brachial artery
| Crossing to the medial side of the brachial a. and entering the cubital fossa
139
From which cord does the ulnar nerve arise?
Lateral cord
140
What are the root values of the ulnar nerve
C8 and T1
141
Where does the ulnar nerve pass posterior to?
Medial epicodyle
142
In the forearm what does the ulnar nerve run alongside?
The ulnar bone
143
How does the ulnar nerve descend initially
Medial side of brachial artery then entering the posterior compartment
144
Which fracture of the humerus could damage the ulnar nerve?
Medial epidoncyle
145
Which fracture of the humerus could damage the axillary nerve?
Fracture of the surgical neck of the humerus
146
Which fracture of the humerus could damage the radial nerve
Fracture of the radial groove
147
Where is the cubital fossa located?
Front of the elbow
148
What shape is the cubital fossa
Triangular
149
Which artery is contained in the cubital fossa?
Brachial
| Which bifurcates at the apex into radial and ulnar
150
Which artery pulsation can be felt medial to the tendon of biceps brachii in the cubital fossa?
Brachial artery
151
What is the base of the cubital fossa and imaginary line between?
An imaginary line drawn between the two epicondyles of the humerus
152
What is the medial border of the cubital fossa formed by?
Lateral border pronator teres
153
What is the lateral border of the cubital fossa formed by?
Medial border brachioradialis m.
154
What are the contents of the cubital fossa?
```
Biceps tendon
Brachial artery (which bifurcates)
Median nerve
```
155
Which vein is the usual choice for IV injections?
Median cubital vein
156
Which muscle occupies the entire posterior compartment of the arm?
Triceps
157
How many heads does the tricep have?
3
158
What are the 3 heads of the triceps?
Long head
Medial head
Lateral head
159
Where does the long head of the triceps originate from
Scapula
160
Where do the lateral and medial heads of the triceps originate from?
Humerus
Lateral- superior radial groove
Medial - inferior radial groove
161
Where does the common tendon of the triceps insert into?
Olecranon process of the ulna
162
Olecranon process and coronoid process are parts of which forearm bone?
Ulna
163
Which head of the triceps has its proximal attachment on the infraglenoid tubercle of the scapula?
Long head
164
What is the main action of the triceps on the elbow joint?
Extension of arm at elbow joint
165
What type of joint is the elbow joint?
Synovial hinge
166
What type of joint is the glenohumeral (shoulder) joint?
Ball and socket
167
What is the nerve supply to the triceps and aconeus muscle?
Radial nerve (remember posterior compartment)
168
What is the action of the aconeus on the elbow joint?
Extension at the elbow
169
Which cord from th brachial plexus does the radial nerve originate from
Posterior cord
170
What are the nerve root values of the radial nerve?
C5-T1
171
What is the characteristic sign of radial nerve injury?
Wrist drop
172
Which branch of the brachial artery accompanies the radial nerve in the radial groove?
Profunda Brachii
173
In which groove does the radial artery travel?
Radial groove
174
In what humerus fracture may the radial nerve be damaged?
In the radial groove in midshaft humeral fractures
175
What type of joint is the elbow joint?
Synovial hinge joint
176
What are the 2 ligaments of the elbow?
Medial (ulnar) collateral ligament
| Lateral (radial) collateral ligament
177
Which ligament of the elbow holds the head of the radius?
Radial (lateral) collateral ligament
178
What are the movements of the elbow joint
Flexion
| Extension
179
What are the 3 flexors of the elbow joint?
Biceps Brachii
Brachialis
Brachioradialis
180
What are the 2 extensors of the elbow joint?
Triceps Brachii
| Aconeus
181
What type of joint is the proximal radio-ulnar joint?
Synovial pivot
182
What type of joint is the distal radio-ulnar joint?
Synovial pivot
183
What movements occur at the radio ulnar joint?
Supination
| Pronation
184
Where is the proximal radio-ulnar joint located?
Immediately distal to elbow joint
185
Which 2 muscles cause pronation of the radio-ulnar joint?
Pronator teres
| Pronator Quadratus
186
Which 2 muscles allow supination of the radioulnar joint?
Supinator
| Biceps Brachii
187
Which ligament holds the head of the radius at the radio-ulnar joint?
Annular ligament
188
Where is the distal radio-ulnar joint located?
Immediately proximal to the wrist joint
189
Which articulation forms the distal radio-ulnar joint?
Ulnar notch of radius
and
Head of Ulnar bone
190
Which articulation forms the proximal radio-ulnar joint?
Radial notch of ulnar
And
Head of Radius bone
191
Which muscle is the most powerful supinator of the forearm?
Biceps Brachii
192
Are muscles of the anterior forearm flexors or extensors?
Flexors of wrist and digits
| Also pronators of forearm
193
What layers are the muscles of the anterior forearm divided into?
Superficial
Intermediate
Deep
194
What are the 4 muscles of the superficial anterior forearm
Pronator teres
Flexor carpi radialis
Flexor Carpi ulnaris
Palmaris longus
195
What is the action of the pronator teres?
Pronation of forearm
196
What is the action of the pronator teres?
Pronation of forearm
197
What is the innervation of the pronator teres muscle?
Median Nerve
198
What is the common origin of the superficial anterior forearm muscles?
Medial epicondyle of humerus
199
Apart from flexing the wrist which superficial anterior forearm muscle is involved in adduction of the wrist?
Flexor carpi ulnaris
200
What are the actions of the flexor carpi ulnaris?
Flexion at wrist
| Adduction at wrist
201
Apart from flexing the wrist which superficial anterior forearm muscle is involved in abducting the wrist?
Flexor carpi radialis
202
What are the actions of the flexor carpi radialis?
Flexion at wrist
| Abduction at wrist
203
Which superficial anterior forearm muscle is innervated by the ulnar nerve?
Flexor carpi ulnaris
204
Apart from the flexor carpi ulnaris which nerve innervates the other 3 superficial anterior forearm muscles
Median nerve
205
In which compartment of the forearm is the brachioradialis located?
Posterior/Extensor Compartment
206
On which joint does the brachioradialis act on?
Elbow joint
207
What is the innervation of the brachioradialis?
Radial nerve
208
What is the main action of the brachioradialis
Flexion at the elbow joint
209
Which muscles are contained in the intermediate group of the anterior forearm?
Flexor Digitorum Superficialis
210
Why is the flexor digitorum superficialis called this?
Because it is superficial to the flexor digitorum profundus
211
How many tendons does the flexor digitorum superficialis give rise to?
4
212
To which digits are the 4 tendons of the flexor digitorum superficialis attached to?
Metacarpal 2,3,4,5
213
On to which phalanx are the tendons of the flexor digitorum superficialis
Middle Phalanx
214
What is the action of the flexor digitorum superficialis
Flexion wrist
Flexion metacarpophlangeal joints (2,3,4,50
Flexion interphalangeal joints (2,3,4,5)
215
What is the innervation
| of the flexor digitorum superficialis
Median Nerve
216
Name the muscles of the deep group of the anterior forearm
Flexor digitorum Profundus
Flexor pollicis longus
Pronator quadratus
217
What is the action of the flexor digitorum profundus?
Flexes distal interphalangeal joints (2,3,4,5)
Flexes metacarpophalangeal joints (2,3,4,5)
Flexes wrist
218
What is the main action of the FDP on the the wrist and finger joints?
Flexion
219
What is the innervation of the FDP? (flexor digitorum profundus?)
Medial half by ulnar nerve
| Lateral half by median nerve
220
Why is the flexor digitorum profundus (FDP) said to have dual nerve supply?
Because half is innervated by the median nerve and half is innervated by the ulnar nerve
2 nerves supply this muscle
221
Onto which phalanx does the FDP tendons attach?
Distal phalanx
222
What is the action of the flexor pollicis longus?
Long flexor of the thumb
223
What shape is the pronator quadratus muscle?
Square shaped
224
What is the action of the pronator quadratus muscles?
Pronation of the forearm
225
What is the innervation of the pronator quadratus muscle?
Median nerve
226
Which nerve is the main nerve of the anterior compartment of the forearm?
Median nerve
227
Which muscles does the median nerve not supply in the forearm?
Flexor carpi ulnaris
| Medial half of flexor digitorum profundus
228
Does the median nerve enter the hand by passing below or above the flexor retinaculum?
Below
229
How does the ulnar head enter the forearm
By passing between the heads of the flexor carpi ulnaris muscle
230
Which bone does the ulnar artery descend close to?
Ulnar bone
231
The ulnar nerve is .... to the ulnar artery
Medial
232
What are the 2 terminal branches of the brachial artery
Radial artery
| Ulnar artery
233
Which arterial pulse can you feel at the distal third of the forearm medial to the tendon of flexor carpi radialis muscle?
Radial pulse
234
Is the carpal tunnel superficial or deep to the flexor retinaculum?
Deep
235
What are the contents of the carpal tunnel
Median nerve
4 tendons of the Flexor Carpi Superficialis
4 tendons of the Flexor carpi Profundus
1 tendon of flexor pollicis longus
236
Which is the most sensitive structure in the carpal tunnel that could be affected in carpal tunnel syndrome?
Median nerve
237
Which muscle of the forearm is continuous with the fascia of the palm shown above?
Palmaris longus
238
What are the 5 muscle compartments of the hand?
```
Thenar compartment
Hypothenar compartment
Adductor compartmnt
Lumbricals and long flexor tendon (central compartment)
Interosseous compartment
```
239
Which nerve innervates all thenar muscles?
Median nerve
240
Name the 3 thenar muscles
Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollicis
241
What is the action of the abductor pollicis brevis?
Abducts thumb
242
What is the action of the flexor pollicis brevis
Flexes MCP joint thumb
243
What is the action of the Opponens pollicis
Opposes thumb to little finger
244
Which muscles produce the hypothenar eminence on the medial palm?
Hypothenar muscles
245
Name the hypothenar muscles
Abductor digiti minimi
Flexor digiti minimi
Opponens digiti minimi
246
Which nerve innervates all the hypothenar muscles?
Ulnar nerve
247
What do the muscle bellies of the thenar muscles produce?
The thenar eminence
248
What is the action of the abductor digiti minimi
Abducts little finger
249
What is the action of the flexor digiti minimi?
Flexes MCP of little finger
250
What is the action of the opponens digit minimi?
Rotates metacarpal of little finger towards palm
251
What are the 2 heads of the adductor pollicis?
Transverse head
| Oblique head
252
Which nerve innervates the adductor pollicis muscle?
Ulnar nerve
253
What is the action of the adductor pollicis on the thumb?
Adducts the thumb
254
Which are the earthworm like muscles?
Lumbricals
255
From which long flexor tendon do these lumbricals originate?
Flexor digitorum profundus
256
What is the action of the lumbrical muscle?
Flex the fingers are the metacarpal joints
Simultaneously
Extend the interphalangeal joint 2nd to 5th digits
257
The medial 2 lumbricals are innervated by
Ulnar nerve
258
The lateral 2 lumbricals are innervated by the
Median nerve
259
Describe DAB and PAD
Dorsal interossei abduct the fingers
| Palmar interossei adduct the fingers
260
What is the action of the dorsal interossei
Abduct the fingers
261
What is the action of the palmar interossei
Adduct the fingers
262
Which nerve innervates the dorsal and palmar interossei
Ulnar nerve
263
Which 2 arteries provide all the blood to the hand?
Ulnar and radial artery
264
What are the 2 palmar arches?
Superficial palmar arch
| Deep palmar arch
265
Which artery is the main contributor of the superficial palmar arch?
Ulnar artery
266
Which artery is the main contributor of the deep palmar arch?
Radial artery
267
Which 2 nerves supply the muscles of the hand
Median nerve
| Ulnar nerve
268
The median nerve enters the hand through
Carpal tunnel
269
The ulnar nerve is a branch of which cord of the brachial plexus?
Medial cord
270
What type of joint is the wrist joint
Synovial condyloid
Or
Synovial Ellipsoid
271
What movements can occur at the wrist joint
```
Flexion
Extension
Circumduction
Adduction (ulnar deviation)
Abduction (radial deviation)
```
272
Which carpal bones form the proximal row of the wrist joint?
Scaphoid
Lunate
Triquentral
Pisiform
273
Which bones forms the distal articular part?
Trapezium
Trapeziod
Capitate
Hamate
274
What is the action of the anterior muscles of the forearm on the wrist joint
Flexion
275
What is the action of the posterior muscles of the forearm on the wrist joint
Extension
276
Is the ulna part of the wrist joint?
No
277
Distally what forms the wrist joint
Proximal row of carpal bones
278
Proximally what forms the wrist joint
Distal end of radius
| Articular disk
279
Which muscles are responsible for the abduction of wrist joint?
Abductor pollicis longus,
Flexor carpi radialis, Extensor carpi radialis longus
Extensor carpi radialis brevis
280
Which muscles are responsible for adduction of the wrist joint?
Extensor carpi ulnaris
| Flexor carpi ulnaris
281
What is the action of the extensor carpi radialis longus and extensor carpi radialis brevis on the wrist joint?
Extension
| Abduction wrist
282
What is the action of the extensor digitorum
Extensor of the fingers and wrist
283
What is the common extensor origin of the posterior forearm
Lateral epicondyle
284
What are the 7 superficial muscles of the posterior forearm?
```
Brachioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor digitorum
Extensor digit minimi
Extensor Carpi ulnaris
Aconeus
```
285
Name the 3 muscles that extend or abduct the thumb in the deep posterior compartment
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
286
What is the innervation of the extensor digitorum
Radial nerve
287
What is the innervation of the extensor carpi radialis longus and brevis
Radial nerve
288
What is the innervation of the extensor carpi ulnaris
Radial nerve
289
What is the innervation of the brachioradialis
Radial nerve
290
What is the innervation of the supinator muscle
Radial nerve
291
What is the innervation of the extensor digit minimi?
Radial nerve
292
What is the main action of the extensor digitorum
Extends medial 4 digits at MCP joints
293
What is the main action of the extensor carpi radialis longus
Extension and abduction of the wrist
294
What is the main action of the extensorecarpi radialis brevis?
Extension and abduction of the wrist
295
What is the main action of the brachioradialis
Flexion at the wrist
296
Why is the brachioradialis muscle an exception to the rules?
Posterior compartment and innervated by radial nerve
| Yet it is a flexor of the wrist not an extensor
297
What is the main action of the extensor carpi ulnaris?
Extension and adduction at the wrist
298
What is the main action of the supinator muscle
Supinates the forearm
299
What is the main action of the extensor digiti minimi
Extends the little finger
300
What is the innervation of the supinator muscle?
Radial nerve
301
What do the deep muscles of the posterior forearm:
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus act on?
Thumb
302
Which nerve innervates the
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus muscles of the thumb?
Posterior interosseous branch of radial nerve
303
What is the main action of the extensor pollicis longus
Extension at MCP and IP (interphalangeal) joint of thumb
304
What is the main action of the extensor pollicis brevis?
Extension of the thumb at the MCP joint
305
What is the difference between the extensor pollicis longus and brevis of the thumb?
Longus extends thumb at all joints
| Brevis extends thumb at MCP joints only
306
What is the main action of the Abducuctor pollicis longus?
Abduction of the thumb
307
Where does the radial nerve divide into the superficial and deep branches?
Cubital fossa
308
What is the deep branch of the radial nerve called?
Posterior interosseous nerve
309
Which 2 carpal bones can you feel in the anatomical snuffbox?
Scaphoid
| Trapezium
310
Which artery lies on the floor of the anatomical snuffbox
Radial artery
311
What makes up the medial (ulnar) border of the anatomical snuffbox?
Tendon of extensor pollicis longus
312
What makes up the lateral (radial) border of the anatomical snuffbox?
Tendon of the extensor pollicis brevis and abductor pollicis longus
