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Flashcards in The Upper Extremity - RR Deck (336):
0

With what does clavicle articulate medially and with what laterally?

Medially with sternum at sternoclavicular joint.
Laterally with acromion at acromioclavicular joint.

1

Where does coracoclavicular ligament attach?

Laterally on clavicle.

2

Where does costoclavicular ligament attach?

Medially on the superior surface of the clavicle.

3

What is the most frequently fractured bone in the body?

The clavicle.

4

What is the usual point in which the clavicles fracture?

At the junction of middle and lateral 3rds of the clavicle.

5

What is the characteristic clinical picture of a patient with fractured clavicle?

Supports the sagging limb with the opposite hand.

6

What structures are at risk in fractures of the middle 3rd?

Subclavian vessels and trunks of the branchial plexus because they lie only behind the thin subclavius muscle.

7

What is a possible complication during healing of a fractured clavicle?

Supraclavicular nerves may be trapped by callous formation - causing chronic neck pain.

8

What is the location of the scapula?

Overlies posterior thoracic wall at ribs 2-7 with spine typically lying at level of spinous process of vertebra T3.

9

What is the role of the acromion?

Articulates with clavicle and overhangs head of humerus as bony point of shoulder.

10

Where is the coracoid process palpable?

Below clavicle under anterior margin of deltoid.

11

What is the role of the coracoid process?

Provides attachment for coracoclavicular, coracoacromial, and coracohumeral ligaments and costocoracoid membrane in addition to muscles.

12

What is the glenoid cavity?

Shallow, deepened slightly by fibrocartilaginous glenoid labrum --> For articulation with head of humerus.

13

How is the suprascapular notch on superior border converted into suprascapular foramen?

By superior transverse scapular ligament.

14

What passes through the suprascapular foramen?

The suprascapular nerve.

15

What is a possible complication during the course of the suprascapular nerve?

May be trapped and compressed as it passes through the suprascapular foramen --> Affects functions of supraspinatus + infraspinatus.
--> Difficulty initiating abduction and weak lateral rotation of the arm.

16

What muscles are inserted in the greater tubercle?

1. Supraspinatus
2. Infraspinatus
3. Teres minor muscles

17

What muscle is inserted in the lesser tubercle?

Subscapularis muscle.

18

Avulsion fractures of the greater tubercle occur with what condition?

In association with anterior dislocation of the shoulder joint.

19

When may the lesser tubercle be avulsed?

In violent lateral rotation of the abducted arm (e.g., a football player attempting to tackle a ball carrier running by).
Or in a rare posterior dislocation of the shoulder joint.

20

What is transmitted through the intertubercular sulcus?

Tendon of long head of biceps branchii muscle --> Bridged by transverse humeral ligament.

21

What is the surgical neck of the humerus?

Proximal end of shaft named for its frequency of fracture.

22

What may be damaged during surgical neck fractures?

May damage axillary nerve and the posterior humeral circumflex artery as they pass through the quadrangular space.

23

What is another name for the intertubercular sulcus?

Bicipital groove.

24

What is the role of the radial groove (spiral groove)?

Separates origins of lateral and medial heads or triceps branchii muscle + radial nerve + profunda branchii artery.

25

What does deltoid tuberosity mark?

Insertion of deltoid muscle about halfway down lateral border.

26

What may be injured during a humeral shaft fracture?

The radial nerve + profunda branchii artery.

27

What may be caused by fractures distal to the deltoid insertion?

Abduction of the proximal fragment by the deltoid --> with the distal fragment pulled proximally by the biceps and triceps.

28

To what does the medial epicondyle of the distal humerus give origin?

To superficial flexor muscles of the forearm.

29

What passes behind the medial epicondyle of the distal humerus?

Grooved posteriorly by the ulnar nerve.

30

To what does the lateral epicondyle give origin?

To superficial extensor muscles of forearm.

31

What may supracondylar humeral fracture cause?

Forearm compartment syndrome.

32

What may be injured with supracondylar fractures?

The brachial artery + median nerve.

33

In what people are the supracondylar fractures common?

In children + in arm wrestlers.

34

What may be caused with anterior displacement of the jagged proximal fragment?

Damage to the attached brachialis --> possibly heterotopic ossification (post traumatic myositis ossficans).

35

Before skeletal maturity (children), what may be a possible complication of forceful abduction of the extended elbow?

Medial epicondyle may be avulsed before skeletal maturity.

36

With what does the head of the proximal radius articulate?

Proximally with capitulum + medially with radial notch of ulna at proximal radioulnar joint.

37

What ligament encircles the head of the radius?

The anular ligament EXCEPT at radial notch of ulna.

38

To what is the neck of the proximal radius related?

To deep radial nerve as it pierces supinator muscle.

39

What is inserted in the tuberosity of radius?

Biceps branchii tendon, just lateral to branchial artery.

40

What separates olecranon from the skin?

The olecranon bursa.

41

How may the olecranon be avulsed?

By forcible triceps branchii contraction or a direct blow.

42

What is "student's elbow"?

Olecranon bursitis caused by repeated friction against the olecranon bursa.

43

What is the distal attachment of brachialis muscle?

The coronoid process.

44

What is the role of radial notch?

It is lateral facet for head of radius at proximal radioulnar joint.

45

What is the role of the ulnar notch?

Medial facet for head of ulna at distal radioulnar joint.

46

What is the styloid process?

Lateral prolongation of radius, PALPABLE in anatomical snuffbox.

47

What may occur with transverse fractures of the distal radius?

Shortening of the radius, with the radial styloid process repositioned proximal to the ulnar styloid process.
--> the roughened dorsal tubercle of the radius may rupture the extensor pollicis longus tendon.

48

What is the Colles fracture?

The distal radial fragment is displaced posteriorly (dinner fork deformity).
--> Common after 50. An individual breaks a fall with an outstretched hand.

49

What is the 2nd MC fracture in women with osteoporosis?

Colles fracture.

50

What happens in Smith fracture?

The distal fragment of the radius is anteriorly displaced.

51

Carpal bones: proximal row --> Lateral to medial.

Scaphoid --> lunate --> triquetrum --> pisiform.

52

Carpal bones: distal row --> Lateral to medial.

Trapezium --> trapezoid --> capitate --> hamate.

53

Where does scaphoid (navicular) lie?

In floor of anatomical snuffbox.

54

What is the most frequently fractured carpal bone, with a risk of avascular necrosis?

The scaphoid bone.

55

True or false? Scaphoid fractures may not show on radiographs for 10d to 2 weeks.

TRUE!!!

56

What may deep tenderness in the anatomical snuffbox indicate?

Scaphoid fracture.

57

What may be caused by forced hyperextension of the wrist?

Anterior dislocation of the lunate --> compressing the median nerve.

58

Is pisiform palpable?

Yes - palpable sesamoid bone in tendon of flexor carpi ulnaris.

59

What does the trapezium form?

A saddle joint with 1st metacarpal bone.

60

When is the hook of the hamate bone frequently ruptured?

In racket sports and golf.

61

What is the Guyon canal?

Dense connective tissue converts the depression between the hook of hamate and the pisiform into Guyon canal (ulnar tunnel).

62

What is a possible problem with Guyon canal?

The ulnar nerve may be compressed by a ganglion cyst.

63

When are the necks of metacarpal bones frequently fractured?

During fistfights.

64

What is called "the boxer's fracture"?

A fractured neck of fifth metacarpal.

65

What is the ONLY true joint between upper extremity and axial skeleton?

The sternoclavicular joint.

66

Is the sternoclavicular joint stable?

It is so stable that the clavicle usually will fracture before the joint dislocates.
--> if the joint dislocates it is usually anteriorly.

67

What may be caused by a posterior dislocation of the sternoclavicular joint?

May compress the trachea and great vessels.

68

Like what do movements of scapula on thoracic wall function?

Like a JOINT (functional joint).

69

What muscles are responsible for elevation of the scapula?

1. Trapezius (upper fibers)
2. Levator scapulae

70

What muscles are responsible for depression of the scapula?

1. Gravity
2. Trapezius (lower fibers)
3. Serratus anterior (lower fibers)

71

Which muscles are necessary for an individual to be able to walk with axillary crutches or negotiate wheelchair transfers?

1. Latissimus dorsi
2. Pectoralis major

72

Which muscles are responsible for the superior rotation of the scapulothoracic joint?

1. Serratus anterior
2. Trapezius muscle (upper and lower fibers together)

73

Which muscles are responsible for inferior rotation of the scapulothoracic joint?

1. Levator scapulae
2. Rhomboid major + minor

74

Which muscles are responsible for protraction of the scapulothoracic joint?

1. Serratus anterior
2. Pectoralis minor muscles

75

Which muscles are responsible for retraction of the scapulothoracic joint?

1. Trapezius (middle fibers)
2. Rhomboid major + minor

76

What happens in shoulder separation?

Acromioclavicular joint dislocates with tearing of the coracoclavicular ligament.

77

For how much of shoulder abduction does the shoulder joint account?

For 120 degrees. (Scapular rotation for 60 degrees).

78

What muscle produce flexion of the glenohumeral joint?

1. Deltoid (anterior fibers)
2. Coracobrachialis
3. Biceps
4. Pectoralis major

79

Which muscles produce extension of the glenohumeral joint?

1. Latissimus dorsi
2. Deltoid (posterior fibers)
3. Teres major
4. Long head of triceps

80

Which muscle abduct the glenohumeral joint?

1. Supraspinatus (initiation)
2. Deltoid

81

Which muscles adduct the glenohumeral joint?

1. Pectoralis major
2. Latissimus dorsi
3. Teres major

82

Which muscles rotate medially the glenohumeral joint?

1. Subscapularis
2. Pectoralis major
3. Deltoid (anterior fibers)
4. Latissimus dorsi
5. Teres major

83

Which muscles rotate laterally the glenohumeral joint?

1. Infraspinatus
2. Teres minor
3. Deltoid (posterior fibers)

84

What is the most frequently dislocated large joint?

The shoulder joint.

85

What is the usual shoulder dislocation?

Anterior-inferior dislocation.

86

Which nerve may be injured during the anterior-inferior shoulder dislocation?

The axillary nerve.

87

Discuss the various muscles and nerves that play a role in abduction of the arm.

1. Supraspinatus (suprascapular nerve) --> first 15 degrees.
2. Deltoid (axillary nerve) --> to the horizontal position.
3. Trapezius (accessory nerve) --> above horizontal.
4. Serratus anterior (long thoracic) --> above horizontal.
Injury to these muscles or nerves compromise abduction.

88

What is usually the cause of subacromial bursitis?

It is often due to deposition of calcium within the supraspinatus tendon (calcific supraspinatus tendinitis) in middle-aged males.

89

In subacromial bursitis, what does the patient typically experience?

A painful arc of movement from 50 to 130 degrees of abduction.

90

What is the Popeye deformity?

Ruptured long head of the biceps --> muscle belly contracts into a ball in the anterior arm on attempted elbow flexion.

91

Which disorders may cause pain referred to the shoulder?

1. Cervical disc herniation
2. Angina pectoris
3. Pleuritis
4. Cholecystitis
5. Ruptured spleen

92

What is the ONLY muscle that can elevate the shoulder?

Trapezius.

93

Which muscles produce flexion of the elbow joint?

1. Brachialis
2. Biceps branchii
3. Brachioradialis

94

Which muscle extend the elbow joint?

1. Triceps branchii
2. Anconeus

95

What is the MAIN flexor of the elbow?

Brachialis

96

What is the role of biceps brachii?

Flexes and assist in supination.

97

Which nerve innervates BOTH brachialis and biceps brachii?

Musculocutaneous nerve.

98

What happens when brachialis and biceps brachii are paralyzed?

Brachioradialis provides some ability to flex the elbow - RADIAL nerve.

99

What happens in a supracondylar fracture of the humerus, regarding medial/lateral epicondyle and olecranon?

They maintain their triangular relationship.

100

What happens in elbow dislocation regarding the olecranon?

It aligns with the epicondyles.

101

What is the target group of posterior dislocations?

Children.

102

What is the importance of radioulnar joints?

Necessary for pronation and supination of forearm --> compensating for lack of rotation at wrist.

103

What is the result of median nerve injury at or above the elbow?

Paralyzes the pronator quadratus + pronator teres muscle.
--> Loss of ability to pronate the arm.

104

What happens when the supinator muscle is paralyzed from a radial nerve lesion?

Biceps branchii can still supinate the forearm.

105

What is the role of the proximal radioulnar joint?

Allows head of radius to rotate in ring formed by radial notch of ulna + anular ligament --> its main stabilizer.

106

Why we must not lift a preschool child by the forearm or hand?

Because it may dislocate the head of the radius from the anular ligament.

107

What is important to remember about infections of the elbow joint?

Always involve the proximal radioulnar joint because of their shared joint cavity.

108

What are the 2 movements of proximal and distal radioulnar joints?

Pronation and supination.

109

Which muscles produce pronation of the proximal and distal radioulnar joints?

1. Pronator quadratus
2. Pronator teres

110

Which muscle produce supination of proximal and distal radioulnar joints?

1. Supinator
2. Biceps brachii

111

What is the importance of the interosseous membrane between ulna and radius?

Allows much of the force applied at the wrist to be transferred from the radius to the ulna, which has more stable articulation with humerus.

112

Which muscles produce flexion of the radiocarpal (wrist) joint?

1. Flexor carpi ulnaris
2. Flexor carpi radialis
3. Palmaris longus
4. Long finger flexors

113

Which muscles produce extension of the wrist joint?

1. Extensor carpi ulnaris
2. Extensor carpi radialis longus and brevis

114

Which muscles abduct the wrist joint?

1. Flexor carpi radialis
2. Extensor carpi radialis longus and brevis

115

Which muscles adduct the wrist joint?

1. Flexor carpi ulnaris
2. Extensor carpi ulnaris

116

What movement is necessary for effective finger flexion?

Wrist extension.

117

What is the carpometacarpal joint of thumb?

Saddle joint between 1st metacarpal and TRAPEZIUM allowing:
1. Thumb opposition
2. Adduction
3. Abduction
4. Flexion
5. Extension

118

Which muscles produce flexion of the thumb?

Flexor pollicis brevis and longus.

119

Which muscles produce extension of the thumb?

1. Abductor pollicis longus
2. Extensor pollicis brevis
3. Extensor pollicis longus

120

Which muscles produce abduction of the thumb?

1. Abductor pollicis longus
2. Abductor pollicis brevis

121

Which muscles produce adduction of the thumb?

Adductor pollicis muscle.

122

Which muscles produce opposition of the thumb?

Opponens pollicis muscle.

123

Which muscles produce flexion of the metacarpophalangeal joints of fingers?

1. Lumbricals
2. Interossei
3. Flexor digitorum superficialis and profundus muscle
--> Wrist extensors are synergist muscles necessary for effective finger flexion.

124

Which muscles produce extension of the MP joint of fingers?

1. Extensor digitorum
2. Extensor indicis (finger 2)
3. Extensor digiti minimi

125

Which muscles produce abduction of the MP joints?

Dorsal interosseous muscles.

126

Which muscles produce adduction of the MP joints of fingers?

Palmar interosseous muscles.

127

What is important to remember about MP joint abduction-adduction?

Can happen ONLY in EXTENSION due to collateral ligaments.

128

What is important to remember about metacarpophalangeal joint of the thumb?

Acts with CARPOMETACARPAL (CM) joint in many movements.

129

Which muscles produce flexion of the MP joint of the thumb?

1. Flexor pollicis brevis
2. Flexor pollicis longus

130

Which muscles produce extension of the MP joint?

1. Extensor pollicis brevis
2. Extensor pollicis longus

131

Which muscles produce flexion of the interphalangeal (IP) joints of fingers?

1. Flexor digitorum superficialis (PIP)
2. Flexor digitorum profundus (DIP)

132

Which muscles produce extension of the IP joints?

1. Extensor digitorum
2. Lumbricals
3. Interossei
4. Extensor indicis
5. Extensor digiti minimi

133

What is the role of the rotator (musculotendinous) cuff?

1. Stabilizes shoulder joint - holding head of humerus in glenoid fossa.
2. Reinforces joint on all sides except inferiorly, where dislocation usually occurs initially (before muscular traction pulls humeral head into subcoracoid position).

134

Which are the muscles of the rotator cuff?

1. Supraspinatus
2. Infraspinatus
3. Teres minor
4. Subscapularis
"SITS"

135

If the rotator cuff muscles are injured, when will the pain be most severe?

At night.

136

What are the boundaries of axilla?

Base --> consists of axillary fascia and skin of armpit.
Apex --> bounded by clavicle, rib 1, and superior border of scapula.
Medial wall --> upper rib cage covered by serratus anterior muscle.
Lateral wall --> formed by intertubercular groove of humerus.
Anterior wall --> consists of pectoralis major and minor muscles.
Posterior wall --> formed by the subscapularis, teres major, and latissimus dorsi muscles.

137

What are the contents of the axilla?

1. Axillary artery/vein
2. Parts of brachial plexus and its branches
3. Axillary sheath - extension of prevertebral layer of deep cervical fascia enclosing axillary vessels and brachial plexus.
4. Axillary lymph nodes - which are often the first involved in breast cancer.

138

When does the subclavian artery become axillary?

At lateral border of rib 1.

139

When does the axillary artery becomes brachial?

At inferior border of teres major.

140

What crosses the axillary artery anteriorly?

Pectoralis minor --> divides it into 3 parts.

141

What is the relationship of the 2nd part of the axillary artery and brachial plexus?

The artery is located medially, laterally, and posteriorly to cords of brachial plexus.

142

What are the branches of the 1st part of the axillary artery?

Superior thoracic artery (only 1 branch).

143

What does the superior thoracic artery supply?

Area over upper two intercostal spaces and pectoral muscles.

144

What are the branches of the 2nd part of the axillary artery?

1. Thoracoacromial
2. Lateral thoracic

145

What does the thoracoacromial artery supply?

Multiple branches piercing clavipectoral fascia to supply pectoral and shoulder regions.

146

What does the lateral thoracic artery supply?

Descends along lateral chest wall to supply serratus anterior and breast.

147

What are the branches of the 3rd part of axillary artery?

1. Subscapular
2. Anterior humeral circumflex
3. Posterior humeral circumflex

148

What are the branches of the subscapular artery?

1. Scapular circumflex artery
2. Thoracodorsal artery

149

Through which space does the scapular circumflex artery pass?

Through triangular space.

150

What is the course of thoracodorsal artery?

Accompanies thoracodorsal nerve to latissimus dorsi.

151

In case of blockage of axillary artery (e.g. By atherosclerosis), what may happen?

Anastomoses may be formed between branches of the thyrocervical + subscapular arteries --> forming collateral circulation around the scapula.

152

What is the course of posterior humeral circumflex artery?

1. Passes with axillary nerve through quadrangular space.
2. Anastomoses with anterior humeral circumflex artery + ascending branch of profunda brachii artery.

153

What happens with an aneurysm developed in the 1st part of the axillary artery?

It can compress the trunks of the brachial plexus.

154

What must be done to control bleeding of the axillary artery? (e.g., from a ruptured aneurysm)

Compress the subclavian artery against rib 1 or the axillary artery against the proximal humerus.

155

What is the course of the axillary vein?

Continuous with basilic vein --> receives brachial and cephalic veins before becoming subclavian vein.

156

Mention 2 possible complications of the axillary vein?

1. Air emboli - if injured and bleed profusely.
2. Effort thrombosis (Paget-Schroetter syndrome) - spontaneous thrombosis after excessive movements of the shoulder (in baseball pitchers and weightlifters).

157

How is the brachial plexus formed?

By the anterior rami of C5-T1.

158

What happens with prefixed and postfixed brachial plexus?

Prefixed --> formed by anterior rami of C4-C8.
Postfixed --> formed by anterior rami of C6-T2.

159

What comprises the brachial plexus?

"Robert Taylor Drinks Cold Beer"
Roots --> Trunks --> Divisions --> Cords --> Branches.

160

Through which two muscles do the roots of brachial plexus pass?

Between anterior and middle scalene muscles.

161

What 2 nerves are branches of the roots of brachial plexus?

1. Dorsal scapular nerve (C5)
2. Long thoracic nerve (C5-C7)

162

What is the course of dorsal scapular nerve and what does it supply?

Pierces middle scalene to supply levator scapulae and rhomboid muscles.

163

What is the course of the long thoracic nerve and what does it supply?

Pierces middle scalene to supply serratus anterior muscle.

164

What conditions may result in damage of the long thoracic nerve and why?

Radical mastectomy, axillary lymph node dissection, or traumatic injury.
--> It lies on the superficial surface of the serratus anterior.

165

What does injury to the long thoracic nerve produce?

"Winged scapula".

166

What is the origin of upper, middle, and lower trunk of the brachial plexus?

Upper --> C5+C6.
Middle --> C7.
Lower --> C8-T1.

167

What is the course of the trunks of brachial plexus?

Pass behind middle third of clavicle - forming supraclavicular and infraclavicular portions of plexus.

168

What nerves are branches of the trunks of brachial plexus?

1. Suprascapular (C5-6)
2. Nerve to subclavius (C5)

169

What is the course of suprascapular nerve?

Passes through suprascapular foramen to supply supraspinatus and infraspinatus muscles.

170

What is interesting to keep in mind about the nerve to subclavius (C5)?

May give accessory phrenic nerve that joins phrenic nerve at variable level.
--> An accessory phrenic nerve may continue to provide significant innervation to the respiratory diaphragm after injury to the phrenic nerve.

171

What happens at the site of divisions of the brachial plexus?

Separate nerve fibers destined for flexor and extensor compartments of upper extremity.

172

What divisions are responsible for the flexor compartments?

Anterior divisions.
Posterior divisions for flexor compartments.

173

How are the cords of the brachial plexus designated?

As medial, lateral, and posterior according to relationship to 2nd part of axillary artery.

174

How is the posterior cord formed?

By posterior divisions of ALL 3 trunks.

175

What nerves are branches of the posterior cord?

1. Upper subscapular (C5-6)
2. Middle subscapular (thoracodorsal) (C6-8)
3. Lower subscapular (C5-6)
4. Axillary nerve (C5-6)
5. Radial nerve (C5-T1)

176

What does the upper subscapular nerve supply?q

Subscapularis muscle

177

What does the middle subscapular (thoracodorsal) nerve supply?

Latissimus dorsi.

178

What does the lower subscapular nerve supply?

Subscapularis + teres major.

179

What does the axillary nerve supply?

Teres minor + deltoid.

180

What does the radial nerve supply?

Extensor compartment of arm and forearm.

181

How is the lateral cord formed?

By anterior divisions of upper and middle trunk.

182

What nerves are branches of the lateral cord?

1. Lateral pectoral nerve (C5-7)
2. Lateral root of median nerve (C5-7)
3. Musculocutaneous nerve (C5-7)

183

What is the course of lateral pectoral nerve?

Pierces costocoracoid membrane to supply pectoralis major.

184

What is the course of the musculocutaneous nerve?

Pierces coracobrachialis to supply flexor muscles of the Armand then continues as LATERAL ANTEBRACHIAL CUTANEOUS NERVE.

185

How is the medial cord formed?

By anterior division of lower trunk.

186

What are the branches of the medial cord?

1. Medial pectoral nerve (C8-T1).
2. Medial brachial cutaneous nerve (C8-T1).
3. Medial ANTEBRACHIAL cutaneous nerve (C8-T1).
4. Ulnar nerve (C8-T1).
5. Medial root of median nerve (C8-T1).

187

What is the course of the medial pectoral nerve?

Pierces pectoralis minor to supply IT and pectoralis major.

188

What does the medial brachial cutaneous nerve supply?

Medial side of the arm + communicates with intercostobrachial nerve (T2), providing basis for referral of cardiac pain at spinal cord segments T1-2.

189

What does the medial ANTEBRACHIAL cutaneous nerve supply?

Skin of medial forearm along course of basilic vein.

190

What do the ulnar nerve supply?

2 muscles of forearm and most intrinsic muscles of hand + it is SENSORY to skin of medial hand and medial 1+1/2 of fingers.

191

What are the boundaries of the quadrangular space?

1. Surgical neck of humerous
2. Long head of triceps brachii
3. Subscapularis muscle
4. Overlying teres minor and major

192

What passes through the quadrangular space?

1. Axillary nerve
2. Posterior humeral circumflex artery
In jeopardy in fractured surgical neck of humerus or dislocated shoulder.

193

What do the axillary lymph nodes drain?

Upper extremity and upper trunk along branches of axillary vessels.
75% of lymph from BREAST.

194

How many groups are the axillary lymph nodes?

Five, that ultimately drain to subclavian lymph trunk.
1. Pectoral
2. Subscapular
3. Humeral
4. Central
5. Apical

195

What is the exact location of the pectoral lymph nodes?

Lie along the lateral thoracic vessels and drain the lateral quadrants of the breast and anterior thoracic wall.

196

What are the signs of compartment syndrome in the flexor forearm?

1. Compartment pain
2. Impaired cutaneous sensation along ulnar and median nerve distribution in the hand.
3. If untreated --> ischemic necrosis --> resulting flexion deformity --> Volkmann ischemic contracture.

197

Which nerve innervates the flexor compartment of the arm?

Musculocutaneous.

198

Which nerve innervates the extensor compartment of the arm?

Radial.

199

Which spinal cord levels are tested from the biceps reflex?

C5-C6.

200

Which nerves innervate the flexor compartment of the forearm?

The median nerve --> Except:
1. Flexor carpi ulnaris
2. Medial half of flexor digitorum profundis
which are from the ULNAR nerve.

201

Which nerve innervates the extensor compartment of the muscles of the forearm?

Radial nerve or its deep radial/posterior interosseous branch.

202

What is basically lateral epicondylitis?

Tennis elbow.

203

What is basically medial epicondylitis?

Golfer's elbow.

204

What are the boundaries of cubital fossa?

Triangular interval anterior to elbow bounded by:
1. Brachioradialis
2. Pronator teres
3. Line connecting epicondyles of humerus

205

Which structures form the floor and the roof of cubital fossa?

Floor --> Brachialis + supinator muscles.
Roof --> Skin + Fascia + Bicipital aponeurosis.

206

What are the contents of cubital fossa from lateral to medial?

Biceps branchii tendon --> brachial artery --> median nerve.

207

Which structure crosses superficially the bifurcation of brachial artery?

Median cubital vein.

208

What separates the median cubital vein from the underlying brachial artery?

The bicipital aponeurosis --> protects the artery from errant phlebotomy or injection of drugs intended for the venous system.

209

Where do the superficial veins of the arm and forearm begin?

In dorsal venous arch of hand.

210

When does basilic vein become axillary vein?

At lower border of teres major.

211

What is a classic sign of subclavian steal syndrome?

Asymmetry of brachial blood pressure at least 20mm Hg is a classic sign.

212

What happens in subclavian steal syndrome?

Retrograde vertebral artery flow into the subclavian with brainstem hypoperfusion.

213

What may occur during a humeral fracture, regarding the vessels of the arm?

The profunda brachii artery may be injured in the radial groove with the radial nerve.

214

What is the course of the radial artery?

1. Courses under brachioradialis to distal forearm.
2. Lies between flexor carpi radialis and brachioradialis tendons near wrist (where pulse is taken).
3. Winds dorsally through anatomical snuffbox to reach dorsum of hand.

215

What is the course of the ulnar artery?

1. In middle 3rd of forearm is joined by ulnar nerve deep to flexor carpi ulnaris + then distally courses lateral to flexor carpi ulnaris tendon.
2. Passes with ulnar nerve lateral to pisiform and SUPERFICIAL to flexor retinaculum in Guyon canal to reach hand.

216

What happens usually in wrist wounds?

The ulnar artery is often lacerated lateral to the pisiform bone.

217

When is the Allen test performed?

Before a radial artery puncture.

218

What is the common interosseous artery?

Short branch from ulnar artery that divides into anterior and posterior interosseous arteries.

219

What is the course of the anterior interosseous artery and what does it supply?

Descends with anterior interosseous nerve to supply forearm flexor muscles.

220

What is the course of the posterior interosseous artery and what does it supply?

Enters posterior compartment and descends with posterior interosseous nerve to supply forearm extensor muscles.

221

What are the 3 categories of muscles of the hand?

1. Thenar muscles
2. Hypothenar muscles
3. Interosseous and lumbrical muscles

222

Where are the thenar muscles located?

In thenar compartment at the base of the thumb.

223

Which are the thenar muscles?

1. Flexor pollicis brevis
2. Abductor pollicis brevis
3. Opponens pollicis

224

Which nerve innervates the thenar muscles?

The median nerve.

225

Where are the hypothenar muscles located?

In hypothenar compartment at base of finger 5.

226

Which are the hypothenar muscles?

1. Flexor digiti minimi brevis.
2. Abductor digiti minimi
3. Opponens digiti minimi

227

Which nerve innervates the hypothenar muscles?

The ulnar nerve.

228

What is the hypothenar hammer syndrome?

Trauma to the distal ulnar artery by using the palm as a tool to pound may result in aneurysm formation with thromboembolization to the fingers.

229

How many are the interosseous muscles?

4 DORSAL + 3 PALMAR interosseous muscles.

230

Which nerve innervates the interosseous muscles?

Ulnar nerve.

231

How many lumbrical muscles do we have and what is their origin?

4 Lumbricals
--> Originate from tendons of flexor digitorum profundus muscle.

232

What is the innervation of the lumbrical muscles?

Medial 2 --> Ulnar.
Lateral 2 --> Median.

233

What is the origin of the MOTOR innervation to intrinsic muscles of the hand?

Derived mostly from T1 spinal cord segment via median and ulnar nerves.

234

Which nerves innervate the hand cutaneously?

Medial + Ulnar + Radial

235

What is the course of the median nerve at the hand?

1. At wrist lies deep to tendon of palmaris longus when present.
2. Enters hand through carpal tunnel ANTERIOR to long flexor tendons.
3. Give rise to superficial recurrent branch to supply thenar compartment muscles.

236

What other branches does the median nerve give to the hand, besides the superficial recurrent branch to thenar muscles?

1. Digital nerves --> supply palmar skin of lateral 3 +1/2 digits.
2. Supplies 1st + 2nd lumbrical muscles.
3. Supplies dorsal skin over distal phalanges of lateral 3 + 1/2 digits.

237

What is the course of the ulnar nerve?

Enters hand by passing superficial to flexor retinaculum in Guyon canal (ulnar tunnel) --> Terminates by dividing into superficial and deep branches.

238

What do the superficial branches of the ulnar nerve supply?

Palmaris brevis + palmar digital cutaneous nerves to MEDIAL 1 +1/2 digits.

239

What is the course of the deep branches of the ulnar nerve?

Passes through hypothenar muscles and runs with deep palmar arteriar arch deep to long flexor tendons.

240

What do deep branches of ulnar nerve supply?

1. Hypothenar muscles
2. Adductor pollicis
3. Palmar and dorsal interosseous muscles
4. Medial 2 lumbricals

241

What is the cutaneous innervation of dorsum of hand?

1. Primarily by superficial branch of RADIAL nerve to LATERAL 3+1/2 digits and dorsal branch of ULNAR nerve to MEDIAL 1+1/2 digits.
2. Median nerve over DISTAL phalanges of LATERAL 3+1/2 digits.

242

What is the cutaneous innervation of the palm?

By palmar cutaneous + palmar digital branches of median and ulnar nerves.

243

To sum up, which muscles are innervated by the median nerve?

1. Pronator teres
2. Flexor carpi radialis
3. Palmaris longus
4. Flexor digitorum superficialis
5. Flexor digitorum profundus (radial part)
6. Flexor pollicis longus
7. Pronator quadratus
8. Abductor pollicis brevis
9. Flexor pollicis brevis
10. Opponens pollicis
11. 1st + 2nd lumbricals

244

To sum up, which muscles are innervated by the ulnar nerve?

1. Flexor carpi ulnaris
2. Flexor digitorum profundus
3. Hypothenar muscles
4. Palmaris brevis
5. ALL dorsal + palmar interossei
6. Adductor pollicis
7. 3rd+4th lumbricals

245

What is the course of the radial artery in the hand?

1. From dorsum of hand enters palm by passing between heads of 1st dorsal interosseous muscle.
2. Anastomoses with deep branch of ulnar artery to form deep palmar arch.

246

Which are the branches of the radial artery in the hand?

1. Dorsal carpal
2. Princeps pollicis
3. Radialis indicis

247

What is basically the deep palmar arch?

Direct continuation of radial artery that anastomoses with deep branch of ulnar artery.

248

Where does the deep palmar arch lie?

On interosseous muscles deep to long flexor tendons.

249

To what does the deep palmar arch give rise?

To palmar metacarpal arteries.

250

How does the ulnar artery terminate?

By giving a deep palmar branch and then continuing as superficial palmar arch.

251

What is basically the superficial palmar arch?

Continuation of ulnar artery, which usually anastomoses with superficial palmar branch or radial artery.

252

Where does the superficial palmar arch lie?

Immediately deep to palmar aponeurosis.

253

To what does the superficial palmar arch give rise?

To common and proper palmar digital arteries.

254

How can we control a palmar arch bleeding?

Via brachial artery compression.

255

How is the dorsal carpal arterial arch formed?

By anastomosis of dorsal carpal branches of ulnar and radial arteries.

256

To what does dorsal carpal arterial arch give rise?

To dorsal metacarpal and dorsal digital arteries.

257

To what does dorsal carpal arterial arch give rise?

Dorsal metacarpal + dorsal digital arteries.

258

What is the target group of Raynaud phenomenon?

Young females or in males who regularly use vibrating tools (e.g., chain saws).

259

What happens in shoulder-hand syndrome?

A form of reflex sympathetic dystrophy (complex regional pain syndrome).
1. Severe burning pain
2. Hyperesthesia
3. Swelling
4. Trophic skin changes in the hand associated with ipsilateral restricted shoulder motion and pain

260

What may be the cause of shoulder-hand syndrome?

It may follow hand, neck, or shoulder injuries or myocardial infarction.

261

What is basically the palmar aponeurosis?

Thickened deep fascia of palm between thenar and hypothenar eminences.

262

With what does the palmar aponeurosis continue?

Proximally with tendon of palmaris longus (when present) and distally with fibrous flexor sheaths of fingers.

263

What is the role of palmar aponeurosis?

Protects:
1. Superficial palmar arterial arch
2. Digital nerves
3. Underlying long flexor tendons

264

What is the Dupuytren contracture?

Localized fibrosis and shortening of the palmar aponeurosis --> pulling the metacarpophalangeal (and proximal interphalangeal) joint of finger 4, and perhaps finger 5 and others, into flexion.
--> DIP JOINTS NOT INVOLVED.

265

What is the flexor retinaculum (transverse carpal ligament)?

Tough, fibrous connective tissue bridging carpal arch to form carpal tunnel.

266

Where is the flexor retinaculum attached to?

Laterally --> To tubercles of scaphoid and trapezium.
Medially --> To hook of hamate and pisiform.

267

What is the role of the flexor retinaculum?

Keeps long flexor tendons from "bowstringing" when wrist is flexed.

268

How is the carpal tunnel formed?

By carpal arch and flexor retinaculum.

269

What is basically the carpal tunnel?

Confined space with rigid walls that contains the median nerve and long flexor tendons.

270

What is the MC entrapment neuropathy?

Carpal tunnel syndrome.

271

With what is carpal tunnel syndrome associated?

1. Repetitive motion affecting long tendon sheaths.
2. Pregnancy
3. Primary hypothyroidism
4. Chronic infl. diseases such as RA.

272

What is the Tinel sign?

Paresthesia from tapping over a damaged or regenerating nerve.

273

What is the role of the flexor synovial sheaths?

Facilitate movement of long flexor tendons in hand.

274

How many flexor synovial sheaths do we have in the hand?

3 separate synovial sheaths at wrist --> Ulnar + Radial bursa - bursal for flexor carpi radialis.
+ 4 digital synovial sheaths.

275

How can infection travel to the carpal tunnel by the ulnar and radial bursae?

From finger 5 and the thumb, respectively.

276

To what are the long flexor tendons connected to and how?

Connected to dorsal part of their synovial sheath by synovial folds called vincula longus and brevis --> which carry blood supply.

277

What is the trigger finger (stenosing tenosynovitis)?

A narrowing of the fibrous flexor tendon sheath at the metacarpophalangeal joint and/or thickening of the long flexor tendon proximal to the fibrous tunnel.

278

What is the course of the flexor digitorum superficialis tendon?

1. Splits around tendon of flexor digitorum profundus.
2. Inserts on lateral sides of base of middle phalanx of fingers 2-5.

279

What is the course of the flexor digitorum profundus tendon?

1. Passes through the split of flexor digitorum superficialis tendon.
2. Inserts into base of distal phalanx of fingers 2-5.

280

What are basically the fascial spaces of palm?

Potential spaces deep to long flexor tendons.

281

How are the fascial spaces of palm separated?

Into thenar and midpalmar spaces by midpalmar (oblique) fascial septum from palmar aponeurosis to 3rd metacarpal.

282

What may swelling of the dorsum of the hand indicate?

A palmar infection.

283

What is basically the extensor retinaculum?

Thickening of dorsal antebrachial fascia.

284

Where does the extensor retinaculum attach?

Laterally --> Distal radius
Medially --> Styloid process of the ulna + triquetrum + pisiform.

285

What is the role of the extensor retinaculum?

Binds the extensor tendons into place in one of six compartments over wrist.

286

What is the De Quervain disease?

Stenosing tenosynovitis involving the:
1. Abductor pollicis longus
2. Extensor pollicis brevis tendons
in the 1st dorsal wrist compartment.

287

What are the clinical features of De Quervain disease?

1. Pain
2. Tenderness
3. Swelling
over the radial styloid process.
--> Pain may radiate down to the thumb or up the forearm.

288

What is the target group of De Quervain disease?

1. Middle-aged women
2. New mothers who use repetitive hand movements

289

What is the mallet finger deformity?

DIP joint flexion due to extensor tendon avulsion.

290

What is the Boutonniere deformity?

PIP joint flexion and DIP joint hyperextension.

291

In what condition do we see the Boutonniere deformity?

Rheumatoid Arthritis

292

What is the swan neck deformity?

PIP joint hyperextension and DIP joint flexion.

293

What is important to remember about the skin of dorsum?

Loose, allowing fluid to easily collect beneath it.
--> Infection in the palm often causes swelling of the dorsum of the hand, which masks the primary site of infection.

294

What are the boundaries of the anatomical snuffbox?

Anteriorly --> Abductor pollicis longus + extensor pollicis brevis.
Posteriorly --> Extensor pollicis longus.

295

What forms the floor of the anatomical snuffbox?

1. Styloid process of the radius
2. Scaphoid
3. Trapezium

296

What crosses the anatomical snuffbox superficially?

The cephalic vein + superficial branch of radial nerve.

297

What does the anatomical snuffbox contain?

Radial artery as it passes to dorsum of hand.

298

Does the radial nerve innervate any intrinsic hand muscles?

NO!!!

299

What spinal cord level is responsible for shoulder flexion - lateral rotation - abduction?

C5

300

What spinal cord level is responsible for shoulder medial rotation - adduction?

C6-8

301

What spinal cord level is responsible for elbow flexion?

C5-6

302

Which spinal cord level is responsible for elbow extension?

C7-8

303

Which spinal cord level is responsible for forearm pronation?

C7-8

304

Which spinal cord level is responsible for forearm supination?

C6

305

Which spinal cord level is responsible for wrist flexion and extension?

C6-7

306

Which spinal cord level is responsible for hand intrinsic muscles?

Mostly T1 with some C8.

307

Which spinal cord level is responsible for digits' flexion and extension?

C7-8

308

What is interesting about radiation-induced nerve damage?

May not appear until years later.

309

What happens in Erb-Duchenne palsy?

Involves spinal nerves C5 and C6 --> Usually when shoulder is wrenched downward and head and neck are forced to opposite side (e.g., violent fall in a motorcycle accident).

310

Mention some other causes of Erb-Duchenne palsy?

1. May occur a birth injury --> difficult delivery.
2. May occur from prolonged pressure on shoulder ("backpacker's palsy") or trauma by a football helmet ("burner" or "stinger"), but with recovery likely.

311

What are the clinical features of Erb-Duchenne palsy?

1. Loss of abduction
2. Loss of flexion
3. Loss of lateral rotation of shoulder
4. Impaired supination of forearm
--> Waiter's tip position with arm hanging at side in medial rotation with forearm extended and pronated and wrist flexed.

312

What happens in Klumpke paralysis?

Involves damage to spinal nerves C8 and T1, which is less common than upper brachial plexus injury.

313

What is usually the cause of Klumpke paralysis?

Often produced by forcibly abducting arm above head (e.g., grabbing for support during fall from height or as a birth injury).

314

In what conditions may Klumpke paralysis occur?

1. Thoracic outlet syndrome
2. Scalenus anterior syndrome
3. May occur with mass lesions
4. Mass lesions --> Pancoast tumor or subclavian artery aneurysm.

315

What are the clinical features of Klumpke paralysis?

1. Affects intrinsic muscles of hand --> clawhand deformity from ulnar nerve loss.
2. Inability to voluntarily flex DIP joints of fingers 4-5 (ulnar half of flexor digitorum profundus).
3. Impaired ulnar deviation (adduction).
4. Flexion of wrist (flexor carpi ulnaris).

316

What is often associated with a lower brachial plexus injury?

Horner syndrome.

317

What are the clinical features of an injury of posterior cord?

1. Paralysis of extensor muscles of arm and forearm with variable flexion at shoulder, elbow, wrist, and fingers.
2. Wristdrop - loss of effective finger function.

318

What may be the cause of injury of posterior cord?

Improperly fitted or incorrectly used axillary crutch ("crutch palsy") or result from draping arm over back of chair or bench while inebriated ("Saturday night palsy").

319

What happens with injury to long thoracic nerve?

Paralyzes serratus anterior --> inability to abduct or flex arm above horizontal due to loss of scpular rotation.
--> Winged scapula when patient pushes forward against resistance (e.g., wall).

320

What is the usually the cause of an injury to suprascapular nerve?

Entrapment in suprascapular foramen only in branch to infraspinatus at spinoglenoid notch.

321

What does injury to suprascapular nerve cause?

1. Difficulty initiating abduction of arm (supraspinatus).
2. Weakness in lateral rotation (infraspinatus).

322

What happens with injury to subscapular nerves?

Weakness in medially rotating arm --> subscapularis + teres major.

323

What happens with injury to thoracodorsal nerve?

1. Decreased strength in adduction, extension, and medial rotation of arm (latissimus dorsi).
2. Impedes walking with crutches and transferring from wheelchairs from weakened shoulder depression (latissimus dorsi).

324

What happens with injury to musculocutaneous nerve?

Greatly weakens flexion of elbow (biceps and brachialis) and supination of forearm (biceps).
--> May be accompanied by anesthesia over lateral aspect of forearm.

325

What may injure the axillary nerve?

A fracture of surgical neck of humerus or dislocation of shoulder joint.

326

What does injury to axillary nerve cause?

Inability to abduct arm beyond first 15 degrees with flattening of shoulder contour (deltoid).
--> LOSS of cutaneous sensation over deltoid.

327

What are the clinical features of radial nerve injury?

1. Wristdrop - paralysis of extensors --> Variable depending on the site of injury.
2. Because cutaneous nerves overlap --> may only a small area of sensory loss over 1st dorsal interosseous muscle.
3. NOT prevent extension of IP joints when combined with metacarpophalangeal flexion from action of interossei and lumbricals.
4. NOT cause complete loss of supination because biceps brachii can partially compensate for paralysis of supinator.

328

What happens with radial nerve injury in arm?

1. Commonly caused by fracture of humeral shaft.
2. Usually does not result in extension at elbow because branches to triceps arise proximal to radial groove.

329

What can cause radial nerve injury at cubital fossa?

1. Hypertrophy or scarring of supinator (through which deep branch passes).
2. Fracture of neck of radius.

330

Why does radial nerve injury at cubital fossa NOT cause wristdrop?

Because branches to extensor carpi radialis longus and brevis arise proximal to this point.
--> Does cause loss of MP joint extension.

331

What causes commonly injury to median nerve?

1. Supracondylar fracture of humerus
2. Laceration at wrist
3. Compression in carpal tunnel

332

What happens with lesion in the recurrent branch of median nerve lesion?

Loss of thumb opposition.

333

What happens with median nerve injury at elbow?

Benediction hand when trying to make a fist.

334

What are the Martin-Gruber anastomoses?

Some individuals have median-ulnar communications in forearm.

335

What happens with an ulnar nerve injury at the medial epicondyle?

Affects most intrinsic hand muscles.