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Upper Extremity Flashcards

1
Q

Origin: Trapezius

A
  1. Medial part of superior nuchal line
  2. Ligamentum nuchae (an expansion of the supraspinous ligament)
  3. Thoracic spinous processes
  4. Supraspinous ligament
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2
Q

Insertion: Trapezius

A
  1. Lateral part of the clavicle
  2. Acromion
  3. Spine of the scapula
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3
Q

Innervation: Trapezius

A

Motor from spinal portion of accessory nerve (CN XI)

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4
Q

Action: Trapezius

A
  1. Acting as a whole, trapezius rotates scapula upward
  2. Acting individually,
    a. Upper trap: rotates scapula upward
    b. Middle trap: retracts (adducts) scapula
    c. Lower trap: depresses and upwardly rotates scapula
    eg: cyclist extending neck over handlebars, holding phone between shoulder and ear, carrying bags on shoulder, pulling shoulders back
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5
Q

Notes: Trapezius

A

Most superficial layer of superficial back muscles

Nerve runs on deep side of muscle with superficial branch of transverse cervical artery

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6
Q

Origin: Latissimus Dorsi

A
  1. Spinous processes of T7-T12
  2. Lumbar aponeurosis (thoracolumbar fascia)
  3. Crest of ilium
  4. Lower 3 or 4 ribs
  5. Inferior angle of scapula
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7
Q

Insertion: Latissimus Dorsi

A

Floor of bicipital groove of humerus

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8
Q

Innervation: Latissimus Dorsi

A

Thoracodorsal nerve (from brachial plexus)

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9
Q

Action: Latissimus Dorsi

A
  1. Shoulder extension
  2. Shoulder internal rotation
  3. Shoulder adduction
  4. Can also contribute to scapular depression and retraction (adduction)

eg: paddling a kayak, walking with crutches, unzipping dress

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10
Q

Notes: Latissimus Dorsi

A

Most superficial layer of superficial back muscles

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11
Q

Origin: Levator Scapulae

A

Transverse processes of C1-C4

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12
Q

Insertion: Levator Scapulae

A

Vertebral border between the spine and the superior angle of scapula

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13
Q

Innervation: Levator Scapulae

A

Dorsal scapular nerve

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14
Q

Action: Levator Scapulae

A
  1. Elevation of scapula
  2. Downward rotation of scapula

eg: rotating head, holding phone between ear and shoulder

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15
Q

Notes: Levator Scapulae

A

Intermediate layer of superficial back muscles

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16
Q

Origin: Rhomboid Minor

A

Spinous processes of C7 and T1

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17
Q

Insertion: Rhomboid Minor

A

Vertebral border of scapula at base of spine

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18
Q

Innervation: Rhomboid Minor

A

Dorsal scapular nerve

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19
Q

Action: Rhomboid Minor

A
  1. Downward rotation of scapula
  2. Retraction (adduction) of scapula
  3. Elevation of scapula
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20
Q

Notes: Rhomboid Minor

A

Intermediate layer of superficial back muscles

Nerve lies on deep surface with deep branch of transverse cervical artery

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21
Q

Origin: Rhomboid Major

A

Spinous processes T2-T5

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22
Q

Insertion: Rhomboid Major

A

Vertebral border of scapula below rhomboid minor to the inferior angle

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23
Q

Innervation: Rhomboid Major

A

Dorsal scapular nerve

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24
Q

Action: Rhomboid Major

A
  1. Downward rotation of scapula
  2. Retraction (adduction) of scapula
  3. Elevation of scapula
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25
Notes: Rhomboid Major
Intermediate layer of superficial back muscles
26
Origin: Serratus Posterior Superior
Spinous processes of C7-T2
27
Insertion: Serratus Posterior Superior
Upper ribs
28
Innervation: Serratus Posterior Superior
Intercostal nerves T2-T5 (ventral rami)
29
Action: Serratus Posterior Superior
Assists in lifting ribs in inspiration
30
Notes: Serratus Posterior Superior
Deepest layer of superficial back muscles
31
Origin: Serratus Posterior Inferior
Spinous processes T11-L2
32
Insertion: Serratus Posterior Inferior
Lower ribs
33
Innervation: Serratus Posterior Inferior
Intercostal nerves T9-T12 (ventral rami)
34
Action: Serratus Posterior Inferior
Unclear, may hold lower ribs down during inspiration
35
Notes: Serratus Posterior Inferior
Deepest layer of superficial back muscles
36
Origin: Serratus Anterior
Digitations from ribs 1-8
37
Insertion: Serratus Anterior
1. Vertebral border on costal surface of scapula | 2. Inferior angle of scapula
38
Innervation: Serratus Anterior
Long thoracic nerve
39
Action: Serratus Anterior
1. Scapula protraction (abduction) 2. Rotates scapula (glenoid) upward eg: push up, throwing a punch, opening a swinging door
40
Notes: Serratus Anterior
Scapular winging if serratus anterior denervated | Important in scapulohumeral rhythm
41
Origin: Deltoid
1. Lower margin of lateral 1/3 of clavicle 2. Acromion 3. Lower margin of scapular spine
42
Insertion: Deltoid
Deltoid tuberosity of humerus
43
Innervation: Deltoid
Axillary nerve
44
Action: Deltoid
1. Acting as a whole, deltoid stabilizes glenohumeral (GH) joint 2. Acting individually, a. Anterior fibers: shoulder flexion and horizontal adduction b. Middle fibers: shoulder abduction c. Posterior fibers: shoulder extension and horizontal abduction
45
Origin: Subscapularis
Costal surface of scapula (subscapular fossa)
46
Insertion: Subscapularis
Lesser tubercle of humerus
47
Innervation: Subscapularis
Upper and lower subscapular nerves
48
Action: Subcapularis
1. Stabilizes GH (glenohumeral) joint 2. Shoulder internal rotation eg: reaching hand around to scratch back; clutching a book to chest
49
Notes: Subscapularis
Rotator cuff muscle
50
Origin: Supraspinatus
Supraspinous fossa
51
Insertion: Supraspinatus
Superior facet of greater tubercle of humerus
52
Innervation: Supraspinatus
Suprascapular nerve
53
Action: Supraspinatus
1. Stabilizes GH joint 2. Shoulder abduction 3. Depresses humeral head during abduction eg: conducting an orchestra, installing ceiling tiles overhead
54
Notes: Supraspinatus
Rotator cuff muscle
55
Origin: Infraspinatus
Infraspinous fossa
56
Insertion: Infraspinatus
Middle facet of greater tubercle
57
Innervation: Infraspinatus
Suprascapular nerve
58
Action: Infraspinatous
1. Stabilizes GH joint 2. Shoulder external rotation eg: starting a pull-cord lawn mower
59
Notes: Infraspinatus
Rotator cuff muscle
60
Origin: Teres Minor
Lateral border of scapula, above teres major
61
Insertion: Teres Minor
Lower facet of greater tubercle
62
Innervation: Teres Minor
Axillary nerve
63
Action: Teres Minor
1. Stabilizes joint 2. Shoulder external rotation eg: starting a pull-cord lawn mower
64
Notes: Teres Minor
Rotator cuff muscle
65
Origin: Teres Major
Lower lateral border of scapula, as far as inferior angle
66
Insertion: Teres Major
Medial lip of bicipital groove
67
Innervation: Teres Major
Lower subscapular nerve
68
Action: Teres Major
1. Shoulder internal rotation 2. Shoulder adduction 3. Shoulder extension
69
Origin: Coracobrachialis
Coracoid process
70
Insertion: Coracobrachialis
Middle shaft of humerus
71
Innervation: Coracobrachialis
Musculocutaneous nerve
72
Action: Coracobrachialis
1. Shoulder flexion 2. Shoulder adduction eg: reaching around face to scratch opposite ear; doing a bench press
73
Notes: Coracobrachialis
Anterior compartment Musculocutaneous nerve pierces coracobrachialis muscle belly
74
Origin: Biceps Brachii
1. Short head: coracoid process | 2. Long head: supraglenoid tubercle (blends with labrum, see notes)
75
Insertion: Biceps Brachii
Radial tuberosity (radius)
76
Innervation: Biceps Brachii
Musculocutaneous nerve
77
Action: Biceps Brachii
1. Elbow flexion 2. Forearm supination 3. Shoulder flexion eg: carrying infant in cradled arms, tightening a screw with right arm, holding heavy hymnal while singing
78
Notes: Biceps Brachii
- Anterior compartment - Tendinous origin of long head runs in fibrous capsule of GH joint (enclosed in synovial membrane,) travels in bicipital groove, held down by transverse humeral ligament - Two tendons fuse into one muscle belly - Prior to insertion gives off bicipital aponeurosis medially, which fuses with deep fascia - In 10% a third head can be found arising from the humerus
79
Origin: Brachialis
Lower, anterior humerus
80
Insertion: Brachialis
Coronoid process
81
Innervation: Brachialis
Musculocutaneous nerve
82
Action: Brachialis
Elbow flexor in both supination and pronation eg: bringing food from plate to mouth; picking up heavy books; carrying baby car seat
83
Notes: Brachialis
Anterior compartment Possibly dual innervation from radial nerve
84
Origin: Triceps Brachii
1. Long head: infraglenoid tubercle 2. Lateral head: posterior humerus above the spiral groove 3. Medial head: posterior humerus below the spiral groove (deep)
85
Insertion: Triceps Brachii
Olecranon process
86
Innervation: Triceps Brachii
Radial nerve
87
Action: Triceps Brachii
1. Elbow extension 2. Long head can adduct and extend shoulder eg: slamming trunk of car; push up; dribbling basketball
88
Notes: Triceps Brachii
Posterior compartment Long head runs anterior to teres minor and posterior to teres major muscles Long and lateral heads form the superficial part of the muscle
89
Origin: Anconeous
Lateral epicondyle of humerus
90
Insertion: Anconeous
1. Lateral surface of olecranon | 2. Lateral ulna
91
Innervation: Anconeous
Radial nerve
92
Action: Anconeous
Elbow extension
93
Notes: Anconeous
Posterior compartment
94
Origin: Pectoralis Major
1. Clavicular head: medial 1/3 of clavicle 2. Sternal head: sternum, upper 6 costal cartilages 3. Aponeurosis of external oblique
95
Insertion: Pectoralis Major
Lateral lip of bicipital (intertubercular) groove of humerus 1. Clavicular fibers insert lower part of groove 2. Sternal fibers insert in higher part of groove
96
Innervation: Pectoralis Major
Medial and lateral pectoral nerves
97
Action: Pectoralis Major
1. Shoulder adduction 2. Shoulder flexion 3. Shoulder internal rotation eg: chin-up, swimming, sawing wood
98
Origin: Pectoralis Minor
Ribs 2-5 (may vary)
99
Insertion: Pectoralis Minor
Coracoid process of scapula
100
Innervation: Pectoralis Minor
Medial and lateral pectoral nerves
101
Action: Pectoralis Minor
1. Protraction of scapula 2. Scapular depression eg: throwing a punch, reaching into deep front pocket, taking deep inhale
102
Origin: Subclavius
First rib
103
Insertion: Subclavius
Clavicle
104
Innervation: Subclavius
Nerve to subclavius
105
Action: Subclavius
Elevates first rib
106
Origin: Pronator Teres
2 heads 1. Medial epicondyle (common flexor origin) 2. Coronoid process of ulna
107
Insertion: Pronator Teres
Mid-radius
108
Innervation: Pronator Teres
Median nerve
109
Action: Pronator Teres
1. Pronation of forearm | 2. Weak flexor of elbow
110
Notes: Pronator Teres
Superficial layer Median nerve passes between 2 heads
111
Origin: Flexor Carpi Radialis
Medial epicondyle (common flexor origin)
112
Insertion: Flexor Carpi Radialis
Base of 2nd metacarpal
113
Innervation: Flexor Carpi Radialis
Median nerve
114
Action: Flexor Carpi Radialis
1. Wrist flexion | 2. Wrist radial deviation (with extensor carpi radialis longus)
115
Notes: Flexor Carpi Radialis
Superficial layer
116
Origin: Palmaris Longus
Medial epicondyle (common flexor origin)
117
Insertion: Palmaris Longus
Palmar aponeurosis
118
Innervation: Palmaris Longus
Median nerve
119
Action: Palmaris Longus
Wrist flexion
120
Notes: Palmaris Longus
Superficial layer Absent in 10%
121
Origin: Flexor Carpi Ulnaris
2 heads 1. Medial epicondyle (common flexor origin) 2. Posterior border of upper ulna
122
Insertion: Flexor Carpi Ulnaris
1. Pisiform 2. Hamate 3. Base of 5th metacarpal
123
Innervation: Flexor Carpi Ulnaris
Ulnar nerve
124
Action: Flexor Carpi Ulnaris
1. Wrist flexion | 2. Ulnar deviation of wrist (with extensor carpi ulnaris)
125
Notes: Flexor Carpi Ulnaris
Superficial layer
126
Origin: Flexor Digitorum Superficialis
2 heads 1. Medial epicondyle (common flexor origin), and coronoid process of ulna 2. Upper radius
127
Insertion: Flexor Digitorum Superficialis
4 tendons insert on each side of base of the middle phalanx, tendons split to allow profundus tendon to pass through
128
Innervation: Flexor Digitorum Superficialis
Median nerve
129
Action: Flexor Digitorum Superficialis
Flexes proximal interphalangeal joint
130
Notes: Flexor Digitorum Superficialis
Intermediate layer Tendons lie in a common synovial sheath under flexor retinaculum that is shared with the flexor digitorum profundus Middle and ring finger tendons are above index and little finger tendons
131
Origin: Flexor Pollicis Longus
1. Middle radius | 2. Interosseous membrane
132
Insertion: Flexor Pollicis Longus
Base of distal phalanx of thumb
133
Innervation: Flexor Pollicis Longus
Median nerve (anterior interosseous nerve)
134
Action: Flexor Pollicis Longus
1. Flexes distal phalanx of thumb at IP joint | 2. Flexes proximal phalanx of thumb at MCP joint
135
Notes: Flexor Pollicis Longus
Deep layer
136
Origin: Flexor Digitorum Profundus
1. Upper 3/4 of ulna | 2. Interosseous membrane
137
Insertion: Flexor Digitorum Profundus
Base of distal phalanx
138
Innervation: Flexor Digitorum Profundus
Dual innervation 1. Median nerve to muscle going to digits 2 and 3 (anterior interosseous nerve) 2. Ulnar nerve to muscle going to digits 4 and 5
139
Action: Flexor Digitorum Profundus
Flexes distal phalanx
140
Notes: Flexor Digitorum Profundus
Deep layer
141
Origin: Pronator Quadratus
Distal ulna
142
Insertion: Pronator Quadratus
Distal radius
143
Innervation: Pronator Quadratus
Median nerve (anterior interosseous nerve)
144
Action: Pronator Quadratus
Pronation of forearm
145
Notes: Pronator Quadratus
Deep layer
146
Origin: Palmaris Brevis
Hypothenar fascia
147
Insertion: Palmaris Brevis
Skin of ulnar border of the hand
148
Innervation: Palmaris Brevis
Ulnar nerve
149
Action: Palmaris Brevis
1. Moves skin | 2. Improves contour for grip
150
Notes: Palmaris Brevis
Hypothenar eminence
151
Origin: Lumbricals
From radial side of tendons of flexor digitorum profundus muscle while leaving common tendon sheath
152
Insertion: Lumbricals
Extensor hood (aponeurosis)
153
Innervation: Lumbricals
1. Median nerve: lumbricals 1 and 2 | 2. Ulnar nerve: lumbricals 3 and 4
154
Action: Lumbricals
Flexion of MCP joints with extension of IP joints
155
Notes: Lumbricals
Pass to radial side of MCP joint
156
Origin: Adductor Pollicis
2 heads 1. Transverse from 3rd metacarpal 2. Oblique from base of metacarpals 1, 2, and 3
157
Insertion: Adductor Pollicis
Base of proximal phalanx of the thumb
158
Innervation: Adductor Pollicis
Ulnar nerve
159
Action: Adductor Pollicis
Adduction of the thumb
160
Origin: Palmar Interossei
Each has 1 head arising from the adjacent metacarpal 1. 1st interossei from ulnar side of 2nd metacarpal 2. 2nd interossei from radial side of 4th metacarpal 3. 3rd interossei from radial side of 5th metacarpal
161
Insertion: Palmar Interossei
Extensor aponeurosis
162
Innervation: Palmar Interossei
Deep branch of ulnar nerve
163
Action: Palmar Interossei
1. Adduction and flexion at MCP | 2. Extension at IP
164
Origin: Dorsal Interossei
Each interossei has 2 heads arising from the adjacent metacarpal
165
Insertion: Dorsal Interossei
Proximal phalanx and extensor tendon (hood) a. 1st interossei to radial side of index finger b. 2nd interossei to radial side of middle finger c. 3rd interossei to ulnar side of middle finger d. 4th interossei to ulnar side of ring finger
166
Innervation: Dorsal Interossei
Ulnar nerve
167
Action: Dorsal Interossei
1. Abduction and flexion at MCP | 2. Extension at IP
168
Origin: Abductor Pollicis Brevis
1. Distal border of flexor retinaculum | 2. Trapezium
169
Insertion: Abductor Pollicis Brevis
Base of proximal phalanx of thumb
170
Innervation: Abductor Pollicis Brevis
Recurrent branch of median nerve
171
Action: Abductor Pollicis Brevis
Abducts thumb
172
Notes: Abductor Pollicis Brevis
Thenar eminence
173
Origin: Flexor Pollicis Brevis
2 heads 1. Superficial head: distal flexor retinaculum and trapezium 2. Deep head: trapezoid
174
Insertion: Flexor Pollicis Brevis
Base of proximal phalanx of thumb
175
Innervation: Flexor Pollicis Brevis
1. Superficial head: recurrent branch of median nerve | 2. Deep head: ulnar nerve
176
Action: Flexor Pollicis Brevis
Flexes metacarpophalangeal (MCP) joint
177
Notes: Flexor Pollicis Brevis
Thenar eminence
178
Origin: Opponens Pollicis
1. Flexor retinaculum | 2. Trapezium
179
Insertion: Opponens Pollicis
1st metacarpal
180
Innervation: Opponens Pollicis
Recurrent branch of median nerve
181
Action: Opponens Pollicis
Opposition of thumb (movement at carpometacarpal joint)
182
Notes: Opponens Pollicis
Thenar eminence Covered by flexor and abductor brevis muscles
183
Origin: Abductor Digiti Minimi
1. Pisiform bone | 2. Adjacent tendons of flexor carpi ulnaris
184
Insertion: Abductor Digiti Minimi
Base of proximal phalanx of little finger
185
Innervation: Abductor Digiti Minimi
Deep branch of ulnar nerve
186
Action: Abductor Digiti Minimi
Abducts little finger
187
Notes: Abductor Digiti Minimi
Hypothenar eminence
188
Origin: Flexor Digiti Minimi Brevis
1. Flexor retinaculum | 2. Hamate
189
Insertion: Flexor Digiti Minimi Brevis
Proximal phalanx
190
Innervation: Flexor Digiti Minimi Brevis
Deep branch of ulnar nerve
191
Action: Flexor Digiti Minimi Brevis
Flexes MCP joint
192
Notes: Flexor Digiti Minimi Brevis
Hypothenar eminence
193
Origin: Opponens Digiti Minimi
1. Distal flexor retinaculum | 2. Hook of hamate
194
Insertion: Opponens Digiti Minimi
5th metacarpal
195
Innervation: Opponens Digiti Minimi
Deep branch of ulnar nerve
196
Action: Opponens Digiti Minimi
Opposition of little finger
197
Notes: Opponens Digiti Minimi
Hypothenar eminence Covered by abductor and flexor digiti minimi muscles
198
Origin: Brachioradialis
Upper lateral supracondylar ridge of humerus
199
Insertion: Brachioradialis
Lateral radius above styloid process
200
Innervation: Brachioradialis
Radial nerve
201
Action: Brachioradialis
1. Flexion of forearm in neutral position 2. Supinates pronated forearm 3. Pronates supinated forearm eg: turning door handle; whisking cream
202
Origin: Extensor Carpi Radialis Longus
Lower lateral supracondylar ridge
203
Insertion: Extensor Carpi Radialis Longus
Base of second metacarpal
204
Innervation: Extensor Carpi Radialis Longus
Radial nerve
205
Action: Extensor Carpi Radialis Longus
1. Wrist extension | 2. Contributes to radial deviation (with flexor carpi radialis)
206
Origin: Extensor Carpi Radialis Brevis
Lateral epicondyle (common extensor tendon)
207
Insertion: Extensor Carpi Radialis Brevis
Base of third metacarpal
208
Innervation: Extensor Carpi Radialis Brevis
Deep branch of radial nerve
209
Action: Extensor Carpi Radialis Brevis
Wrist extension
210
Origin: Extensor Digitorum
Lateral epicondyle (common extensor tendon)
211
Insertion: Extensor Digitorum
Extensor hood
212
Innervation: Extensor Digitorum
Deep branch of radial nerve
213
Action: Extensor Digitorum
Extension of all joints of the digits
214
Notes: Extensor Digitorum
Extensor hood mechanism a. 3 or 4 tendons pass under retinaculum b. Give off intertendinous connections c. 1st and 4th tendons joined by extensor indicis tendon and tendon of extensor digiti minimi at MCP jt d. At MCP jts the tendons expand laterally to cover the joint and are joined by the insertions of the lumbricals and interossei, forming the extensor aponeurosis (hood) e. Aponeurosis splits into 3 bands, 2 lateral and 1 central f. Central band inserts on the middle phalanx g. Lateral bands come together as one to insert on the distal phalanx
215
Origin: Extensor Digiti Minimi
Lateral epicondyle (common extensor tendon)
216
Insertion: Extensor Digiti Minimi
Extensor hood of 5th finger
217
Innervation: Extensor Digiti Minimi
Deep branch of radial nerve
218
Action: Extensor Digiti Minimi
Extension of the fifth finger
219
Origin: Extensor Carpi Ulnaris
2 heads 1. Lateral epicondyle (common extensor tendon) 2. Middle posterior ulna
220
Insertion: Extensor Carpi Ulnaris
Base of 5th metacarpal
221
Innervation: Extensor Carpi Ulnaris
Deep branch of radial nerve
222
Action: Extensor Carpi Ulnaris
1. Wrist extension | 2. Ulnar deviation (with flexor carpi ulnaris)
223
Origin: Supinator
1. Lateral epicondyle 2. Radial collateral and annular ligaments 3. Supinator crest of the ulna
224
Insertion: Supinator
Upper radius
225
Innervation: Supinator
Deep branch of radial nerve
226
Action: Supinator
Supinates the forearm
227
Notes: Supinator
Radial nerve pierces through supinator muscle belly
228
Origin: Abductor Pollicis Longus
1. Posterior ulna 2. Posterior radius 3. Interosseous membrane
229
Insertion: Abductor Pollicis Longus
Base of the 1st metacarpal
230
Innervation: Abductor Pollicis Longus
Deep branch of radial nerve
231
Action: Abductor Pollicis Longus
Abducts the thumb
232
Origin: Extensor Pollicis Brevis
1. Distal radius | 2. Interosseous membrane
233
Insertion: Extensor Pollicis Brevis
Base of proximal phalanx of thumb
234
Innervation: Extensor Pollicis Brevis
Deep branch of radial nerve
235
Action: Extensor Pollicis Brevis
Extends thumb MCP joint
236
Origin: Extensor Pollicis Longus
1. Posterior ulna 2. Interosseous membrane (see notes)
237
Insertion: Extensor Pollicis Longus
Distal phalanx of thumb
238
Innervation: Extensor Pollicis Longus
Deep branch of radial nerve
239
Action: Extensor Pollicis Longus
Extends thumb
240
Notes: Extensor Pollicis Longus
Origin lies between abductor pollicis longus and extensor pollicis brevis
241
Origin: Extensor Indicis
Posterior distal ulna
242
Insertion: Extensor Indicis
Extensor hood of index finger
243
Innervation: Extensor Indicis
Deep branch of radial nerve
244
Action: Extensor Indicis
Extension of index finger

Anatomy (7 decks)

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