Raftery Upper Limb Flashcards
(398 cards)
1
Q
What is the female breast made of?
A
Fat
Fibrous tissue
Glandular tissue (15-20 lobules)
2
Q
What are the lobules of glandular tissue in the breast separated by?
A
By fibrous septa running from subcutaneous tissues to the fascia of the chest wall (i.e. ligaments of Astley Cooper)
3
Q
What does each gland in the breast drain into?
A
Lactiferous duct, which converges towards the nipple. Each duct becomes dilated to form a lactiferous sinus beneath the areola.
4
Q
What are glands of Montogomery in the breast?
A
Large modified sebaceous glands that lubricate the areola
5
Q
Arterial supply of breast
A
Axillary artery via lateral thoracic and acromiothoracic branches
Internal mammary (thoracic) artery via its perforating branches
Intercostal arteries via perforating branches
(Venous drainage to corresponding veins)
6
Q
Lymphatic drainage of breast
A
Axillary LNs along tributaries of axillary vein
Internal mammary chain along tributaries of internal mammary vessels
(free communication between lymphatic vessels between breast lobules, but lateral part tends to drain towards axilla and medial part towards internal mammary chain)
7
Q
Anatomical classification of axillary nodes
A
Anterior (pectoral) - 3-5 nodes lie deep to pec major in medial wall of axilla along lower border of pectoralis major, related to lateral thoracic artery. Receive lymph mainly from anterior thoracic wall including most of breast.
Posterior (subscapular) - 6-7 nodes along posterior axillary fold and subscapular vessels. Lymph from posterior thoracic wall and scapular region.
Lateral (humeral) - 4-6 nodes posterior to axillary vein, most lymph drained from UL
Central - 3-4 large nodes near base of axilla (deep to pec minor, close to 2nd part of axillary artery) in axillary fat. Lymph from efferent vessels from pectoral, subscapular and humeral axillary LN groups
Apical - immediately behind clavicle at apex of axilla above pectoralis minor. Close to axillary vein (all other axillary nodes drain down this group and also from lymph vessels accompanying cephalic veins)
8
Q
Surgical classification of axillary nodes
A
Level 1 nodes - below and lateral to inferolateral border of pec minor (lateral, anterior and posterior nodes)
Level 2 nodes - behind pec minor (central and some apical nodes)
Level 3 nodes - above upper border of pec minor (apical and infraclavicular nodes)
9
Q
How may a male breast cancer spread when it has infiltrated the normal pathways of lymphatic drainage?
A
Lymphatics of opposite breast
Contralateral axillary nodes
Inguinal lymph nodes
Cervical lymph nodes
10
Q
How are incisions in the breast made?
A
Radially, to avoid cutting across the line of the ducts
11
Q
What is dimpling of the skin over a carcinoma of the breast?
A
It is the result of malignant infiltration and contraction of Cooper’s ligaments
12
Q
What is the shape of the axilla?
A
Pyramidal, with a base, apex and 4 walls
13
Q
Contents of the axilla
A
Axillary artery (3 parts) - medial, posterior and lateral to pectoralis minor (medial and posterior parts travel in axilla)
Axillary vein - lies in apex of axilla, continuation of basilic vein, becomes subclavian vein at outer border of 1st rib
Brachial plexus
Axillary lymph nodes - lymph from UL and pectoral region
Biceps brachii (short head) and coracobrachialis - attach to coracoid process of scapula
Long thoracic nerve (of Bell) - derived from C5-7, passes behind brachial plexus to enter axilla. Lies on medial chest wall, supplies serratus anterior. Damage during axillary surgery causes winging of scapula.
Thoracodorsal nerve and trunk - innervate and vascularise latissimus dorsi
Intercostobrachial nerves - traverse the axillary LNs, often divided during axillary surgery, provide cutaneous sensation to axillary skin
Fat
14
Q
Borders of the axilla
A
Medial - thoracic wall, serratus anterior
Lateral - bicipital/intertubercular groove of humerus/humeral head
Anterior - lateral border of pec major, pec minor, subclavius muscles
Posterior - subscapularis, teres major, lat dorsi
Apex (axillary inlet) - lateral border of 1st rib, superior border of scapula, posterior border of clavicle
Fascia - clavipectoral fascia
15
Q
Boundaries of antecubital fossa
A
Medial - lateral border of pronator teres
Lateral - medial border of brachioradialis
Superior - horizontal line between epicondyles of humerus
Floor - brachialis (proximally) and supinator (distally)
Roof - bicipital aponeurosis, fascia, subcutaneous fat, skin
16
Q
Contents of antecubital fossa
A
(Lateral to medial)
Radial nerve - along lateral border of cubital fossa, divides into superficial and deep branches, motor and sensory function in posterior arm and hand
Biceps tendon - passes centrally through fossa, attaches the radial tuberosity (immediately distal to radial neck), gives rise to bicipital aponeurosis which contributes to roof of cubital fossa
Brachial artery - divides into radial and ulnar arteries at apex of fossa, brachial pulse can be felt by palpating medial to biceps tendon
Median nerve - travels medially through fossa, exiting by passing through 2 heads of pronator teres, motor and sensory function in anterior arm and hand
Roof of cubital fossa also contains a few superficial veins - median cubital vein connecting basilic and cephalic veins
17
Q
Boundaries of carpal tunnel
A
Roof - flexor retinaculum
Floor and walls - concavity of carpal bones (medial to lateral: trapezium, trapezoid, capitate, hamate)
18
Q
Contents of carpal tunnel
A
Median nerve
9 tendons surrounded by synovial sheaths: FDS (4), FDP (4), flexor pollicis longus
Former 2 surrounded by single synovial sheath, latter has its own sheath - sheaths allow free movement of tendons
Note: flexor carpi radialis is located within the flexor retinaculum and not within carpal tunnel itself
19
Q
Why is there no sensory impairment on lateral side of the palm if the median nerve is compressed in the carpal tunnel?
A
The superficial palmar branch innervating the lateral palm is given off proximal to the flexor retinaculum
20
Q
Borders of anatomical snuffbox (radial fossa)
A
Medial - EPL
Lateral - abductor pollicis longus, EPB
Proximal - styloid process of radius
Floor - trapezium, scaphoid
21
Q
Contents of anatomical snuffbox (radial fossa)
A
Radial artery - crosses floor of anatomical snuffbox, then turns medially and travels between heads of adductor pollicis muscle
Superficial branch of radial nerve - innervates dorsal surface of lateral 3.5 digits
Cephalic vein
22
Q
Which structure is close to the dorsal branch of the radial artery?
A
Cephalic vein - site for creating AV fistula for dialysis
23
Q
Lymphatics of upper limb (broadly speaking)
A
Superficial - accompany veins, very few in UL mainly epitrochlear nodes
Efferents from epitrochlear nodes pierce the deep fascia and end in axillary nodes
Deep - accompany arteries
24
Q
Which structures do the axillary nodes drain?
A
Breast Pectoral region Upper abdominal wall down to umbilicus Skin of back down to iliac crest Upper limb
25
What emerges from the axillary nodes?
Subclavian lymph trunk
26
Overview of arteries of the upper limb
```
Subclavian
Axillary
Brachial
Radial
Ulnar
```
27
Start and end points of axillary artery
Starts at lateral border of 1st rib (from subclavian artery)
Ends at lower border of teres major (as brachial artery)
28
Parts of axillary artery
```
Divided into 3 parts by pec minor:
1st part (proximal) - superior thoracic artery
```
2nd part (posterior) - thoracoacromial and lateral thoracic artery
3rd part (distal) - subscapular, anterior and posterior circumflex arteries (latter form anastomotic network around surgical neck of humerus, can be damaged in fractures)
29
Relations of axillary artery
Brachial plexus cords (lateral, medial, posterior) surround the artery
30
Start and end points of brachial artery
Starts at lower border of teres major (from axillary artery)
Ends in cubital fossa at level of neck of radius (divides into radial and ulnar artery)
31
Where does the brachial artery lie in its course?
Immediately below the deep fascia in most of its course where it is readily accessible e.g. for brachial embolectomy.
32
What crosses the brachial artery superficially from lateral to medial side?
Median nerve at level of mid-humerus
33
Start and end points of radial artery
Starts at neck of radius lying on biceps tendon
Distal to the wrist, give off branches contributing to superficial palmar arch
34
Where does the radial artery lie in its course?
Overlapped by brachioradialis in its upper half
In distal forearm - lies between the brachioradialis and FCR (can palpate at wrist)
Closely related to radial nerve in middle of forearm
Passes deep to tendons of APL and EPB to enter anatomical snuffbox
Pierces first dorsal interosseous and adductor pollicis to contribute to deep palmar arch
35
Start and end points of ulnar artery
Starts at neck of radius in middle of antecubital fossa
Passes obliquely downward, reaching ulnar side of forearm midway between elbow and wrist
Crosses in front of flexor retinaculum to divide into superficial and deep volar arches, and form superficial palmar arch with superficial branch of radial artery
36
Where does the ulnar artery lie in its course?
Passes deep to muscles from common flexor origin
Lies on FDP, overlapped by FCU
Median nerve at medial side of artery for ~2.5cm, then crosses it superficially
In distal forearm - becomes superficial between tendons of FDP and FCU
Ulnar nerve lies at medial side in distal 2/3 of forearm and across the flexor retinaculum
37
What separates the median nerve from the ulnar artery?
Deep head of pronator teres
38
What are the veins in UL important for?
Cannulation
| Creation of AV fistula for dialysis
39
Overview of veins of the upper limb
Superficial - cephalic, basilic (combine to form median cubital vein)
Deep (venae comitantes accompanying arteries)
40
Start and end points of superficial veins in upper limb
Starts as dorsal venous network on dorsum of hand
| Dorsal venous network drains into lateral cephalic vein and dorsal basilic vein
41
Where does the cephalic vein lie in its course?
Lies subcutaneously just behind radial styloid
Runs up anterior aspect of forearm
Lies in along lateral border of biceps in upper arm
Passes to deltopectoral triangle (superficial until reaches here)
Pierces clavipectoral fascia to enter axillary vein
42
Path of basilic vein
Originates on medial side of dorsal venous network of the hand
Passes MEDIALLY up forearm and arm (most of its course is superficial), runs in groove along medial border of biceps
Joins cephalic vein near region anterior to cubital fossa
Passes deep under the muscles midway up the humerus
Anterior and posterior circumflex humeral veins feed into it at lower border of teres major
Often joined by medial brachial vein (venae comitantes of brachial artery) before draining into axillary vein
43
Which vein connects the cephalic and basilic vein?
Median cubital vein
44
What separates the median cubital vein at the elbow from the underlying brachial artery?
Tough bicipital aponeurosis
45
What are the components of the brachial plexus and their locations?
Roots - between scalenus anterior and scalenus medius
Trunks - posterior triangle of neck
Divisions - behind clavicle
Cords - in axilla
46
Roots of the brachial plexus
Anterior primary rami of C5-8 and T1
47
Trunks of the brachial plexus
Superior - C5-6
Middle - C7-8
Inferior - C8-T1
48
Divisions of the brachial plexus
Each trunk divides into anterior and posterior divisions
49
Cords of the brachial plexus
Lateral - fused anterior divisions of upper and middle trunks
Medial - anterior division of lower trunk
Posterior - fusion of all 3 posterior trunks
50
What are the nerves that arise from each cord?
Lateral cord - musculocutaneous nerve
Medial - ulnar nerve
Posterior - radial, axillary nerve
Cross-communication between lateral and medial cords - median nerve
51
What is the radius?
One of 2 long forearm bones extending from lateral side of elbow to thumb side of wrist. Has 2 expanded ends, distal end is larger.
52
Relations of radius at its upper end
Articular cartilage - covers medial > lateral side
Articulates with radial notch of ulna by annular ligament
Biceps brachii attaches to radial tuberosity
53
Muscle attachment at shaft of radius
Upper 1/3 of body - supinator, FDS, FPL
Middle 1/3 of body - pronator teres
Lower 1/4 of body - pronator quadratus, tendon of supinator longus
54
Relations of lower end of radius
Quadrilateral
Anterior surface - capsule of wrist joint
Medial surface - head of ulna
Lateral surface - ends in styloid process
Posterior surface - 3 grooves containing: tendons of extensor carpi radialis brevis and longus, EPL and extensor indicis
55
Which nerve forms the terminal branch of the posterior cord of the brachial plexus?
Axillary nerve (C5-6) - divides into anterior and posterior branches
56
What does the axillary nerve innervate?
Deltoid muscle, small patch of skin over deltoid
57
Course of axillary nerve
Descends posterior to axillary artery at lower border of subscapularis, then passes through quadrangular space with posterior circumflex humeral vessels
58
Relations of brachial artery
Posterior - long head of triceps, with radial nerve and profunda vessels intervening
Anterior - overlapped by medial border of biceps, crossed by median nerve in middle of arm
In cubital fossa it is separated from median cubital vein by bicipital aponeurosis
Basilic vein is in contact at most proximal aspect of cubital fossa and lies medially
59
Origin of trapezius muscle
Medial 1/3 of superior nuchal line of occiput
External occipital protruberance
Ligamentum nuchae
Spines of C7 and all thoracic vertebrae and all intervening interspinous ligaments
60
Insertion of trapezius muscle
Posterior border of lateral 1/3 of clavicle
Medial border of acromion
Upper border of crest of spine of scapula
61
Nerve supply of trapezius
Spinal portion of accessory nerve (CN XI)
62
Actions of trapezius muscle
Elevation of shoulder girdle
| Lateral rotation of scapula
63
Relations of ulnar artery
Deep to - pronator teres, FCU, palmaris longus
Lies on - brachialis, FDP
Superficial to flexor retinaculum at wrist
64
Branch of ulnar artery
Anterior interosseous artery
65
Course of long thoracic nerve
Derived from ventral rami of C5-7, close to their emergence from intervertebral foramina
Runs downward and passes either anterior or posterior to middle scalene muscle
Reaches upper tip of serratus anterior muscle and descends on outer surface of this muscle, giving branches to it
66
When does winging of scapula occur?
Long thoracic nerve injury - commonest
Spinal accessory nerve injury - denervates trapezius
Dorsal scapular nerve injury
67
What is the anterior (volar) interosseous nerve a branch of?
Median nerve
68
What does the anterior interosseous nerve supply?
PURE MOTOR
Deep muscles in anterior compartment of forearm:
1. FPL
2. Pronator quadratus
3. Radial half of FDP (lateral 2/4 tendons)
69
Course of anterior interosseous nerve
Accompanies anterior interosseous artery along anterior of interosseous membrane of forearm, in the interval between FPL and FDP
Ends below in pronator quadratus and wrist joint
70
Which joint does the axilla lie under?
Glenohumeral joint, at the junction between UL and thorax
71
Passageways exiting axilla
3 main routes:
1. Immediately inferiorly and laterally, into the UL (majority)
2. Quadrangular space (gap in posterior wall of axilla, structures passing through include axillary nerve and posterior circumflex humeral artery - branch of axillary artery)
3. Clavipectoral triangle (gap in anterior wall) - bounded by pec major, deltoid and clavicle. Cephalic vein enters axilla here, while the medial and lateral pectoral nerves leave
72
What happens when vessels and nerves become compressed between the bones (clavicle, 1st rib, scapula) in the apex of axilla?
Thoracic outlet syndrome
73
Common causes of thoracic outlet syndrome
Trauma e.g. fractured clavicle
Repetitive movements - commonly in jobs with arm lifting
Cervical rib - extra rib from C7 vertebra
74
What is a supracondylar fracture?
Fracture of the distal humerus - usually transverse or oblique
75
Commonest mechanism of injury in supracondylar fracture
FOOSH, commoner in children than adults
76
What can happen if damage to the brachial artery is not repaired?
Volkmann's ischaemic contracture (uncontrolled hand flexion) as forearm flexors become fibrotic and short
77
Damage to which structures can occur in supracondylar fracture?
Brachial artery
Anterior interosseous nerve (branch of median nerve) - weakness of flexor pollicis longus
Ulnar nerve
Radial nerve
78
What is the ulnar (cubital) tunnel?
A fibro-osseous space located on the posteromedial aspect of elbow
Transmits the ulnar nerve from arm into forearm
79
Borders of cubital tunnel
Medial - medial epicondyle of humerus
Lateral - olecranon of ulna
Floor - elbow joint capsule and medial collateral ligament of elbow
Roof - ligament spanning between medial epicondyle and olecranon (cubital tunnel retinaculum aka arcuate ligament of Osborne - band of fascia running between ulnar and humeral heads of flexor carpi ulnaris)
80
Contents of cubital tunnel
Ulnar nerve
After the tunnel, nerve travels between the 2 heads of flexor carpi ulnaris and continues into forearm and hand
81
What is cubital tunnel syndrome?
Compression of the ulnar nerve within the ulnar tunnel.
2nd commonest peripheral neuropathy of UL
82
What is the ulnar (Guyon's) canal?
A fibro-osseous tunnel located at the level of the palm. Transmits ulnar neurovascular bundle from forearm into hand
83
Length of ulnar canal
About 4cm long, extends from proximal aspect of pisiform bone to origin of hypothenar muscles at hook of hamate
84
Borders of ulnar canal
Medial - pisiform, pisohamate ligament, abductor digiti minimi
Lateral - hook of hamate
Roof - palmar carpal ligament
Floor - flexor retinaculum, hypothenar muscles
85
Contents of ulnar canal
Ulnar nerve - divides within canal into superficial (sensory) and deep (motor) branches
Ulnar artery - located on radial aspect of ulnar nerve, gives rise to deep palmar branch, continues laterally across palm as superficial palmar arch
Venae comitantes of ulnar artery
Lymphatic vessels
86
Commonest causes of ulnar canal syndrome
Ganglion cyst
Lipoma
Trauma
87
Layers of carpal tunnel
Deep carpal arch - forms concave surface, converted into tunnel by overlying flexor retinaculum (transverse carpal ligament)
Superficial flexor retinaculum
88
What is the carpal arch of carpal tunnel formed by?
Lateral - scaphoid, trapezium tubercles
| Medial - hook of hamate, pisiform
89
Divisions of median nerve once it passes through carpal tunnel
2 branches:
Recurrent branch - supplies thenar muscles
Palmar digital nerve - sensory innervation to palmar skin and dorsal nail beds of lateral 3.5 digits, motor innervation to lateral 2 lumbricals
90
Origin of subclavian artery
Right - brachiocephalic trunk
| Left - directly from aortic arch
91
Parts of subclavian artey
1st part - origin of subclavian artery to medial border of anterior scalene
2nd part - posterior to anterior scalene
3rd part - lateral border of anterior scalene to lateral border of 1st rib (becomes axillary artery)
92
Which structure can be compressed in axillary artery aneurysm?
Brachial plexus, causing paraesthesia and muscle weakness
93
Which artery does the brachial artery give rise to immediately distal to teres major?
Deep artery (profunda brachii) - supplies structures in posterior aspect of upper arm (e.g. triceps brachii)
94
What does the profunda brachii travel with in the radial groove of humerus?
Radial nerve
95
What does the radial artery supply?
Posterolateral aspect of forearm
Contributes to anastomotic networks surrounding elbow joint and carpal bones
96
What does the ulnar artery supply?
Anteromedial aspect of forearm
Contributes to anastomotic network surrounding elbow joint
97
What does the ulnar arteries divide into?
Anterior and posterior interosseous arteries - supply deeper structures in forearm
98
What is formed when the radial and ulnar arteries anatosmose in the hand?
Superficial and deep palmar arches
99
Where does the ulnar artery enter the hand?
Anterior to flexor retinaculum, lateral to ulnar nerve
100
Where does the radial artery enter the hand?
Dorsally, crossing the floor of the anatomical snuffbox. Then turns medially and travels between heads of adductor pollicis muscle
Radial artery supplies 1 branch to the thumb, index finger and the superficial palmar arch, then continues as deep palmar arch
101
Origins of basilic and cephalic vein
Dorsal venous network of the hand
102
Where does the basilic vein travel in the arm?
Ascends the medial aspect of upper limb, moves deep into arm at border of teres major
103
What happens to the basilic vein at the border of teres major?
Basilic vein moves deep into the arm i.e. combines with brachial veins from deep venous system to form axillary vein
104
Where does the cephalic vein travel in the arm?
Ascends the anterolateral aspect of upper limb, passing anteriorly at the elbow.
105
Where does the cephalic vein travel at the shoulder?
Between the deltoid and pectoralis major (deltopectoral groove)
Enters axilla region via clavipectoral triangle where it empties into axillary vein
106
What is the deep venous system of the upper limb formed by?
Paired veins that accompany and lie on either side of an artery (brachial, ulnar, radial) - vena comitantes
107
What connects the deep and superficial veins of the upper limb?
Perforating veins
108
What is formed from the efferent vessels from apical axillary nodes?
Efferent vessels from apical axillary nodes travel through the cervico-axillary canal and converge to form the subclavian lymphatic trunk
109
What structures do the right and left subclavian trunks drain into?
Right subclavian trunk - right lymphatic duct, enters right venous angle directly (junction of internal jugular and subclavian veins)
Left subclavian trunk - thoracic duct
110
Common causes of axillary lymphadenopathy
Infection of UL resulting in lymphangiitis - lateral (humeral) group usually affected first
Infections of pectoral region and breast
Metastases of breast cancers
111
What is at risk of damage during axillary lymph node dissection?
Long thoracic nerve (causing winged scapula)
| Thoracodorsal nerve
112
Where do the superficial lymphatic vessels of the UL arise from?
Lymphatic plexuses in the skin of hand (networks of lymphatic capillaries beginning in extracellular spaces)
113
Where do the superficial lymphatic vessels of the UL travel?
They travel up the arm in close proximity to major superficial veins
Basilic vein - enter cubital lymph nodes found medial to vein and proximal to medial epicondyle of humerus. They continue up the arm, ending in lateral (humeral) axillary lymph nodes
Cephalic vein - cross proximal part of arm to enter apical axillary lymph nodes, but some enter the more superficial deltopectoral lymph nodes
114
Where do the deep lymphatic vessels of the UL terminate?
Lateral (humeral) axillary lymph nodes
115
From which structures is lymph drained from by the deep lymphatic vessels of the UL?
Joint capsules
Periosteum
Tendons
Muscles
116
Which muscle originates from the subscapular fossa (anterior surface)
Subscapularis
117
Which muscles attach to the coracoid process of the scapula?
Pectoralis minor
Coracobrachialis
Short head of biceps brachii
118
Bony landmarks of scapula and their muscle attachments
Glenoid fossa - articulates with head of humerus to form glenohumeral joint
Supraglenoid tubercle - long head of biceps brachii
Infraglenoid tubercle - long head of triceps brachii
119
Landmarks of posterior surface of scapula and muscle attachments (if any)
Spine - most prominent feature, runs transverse across scapula, dividing it into supraclavicular and infraclavicular fossae
Acromion - projection of spine arching over glenohumeral joint and articulates with clavicle at acromioclavicular joint
Infraspinous fossa - origin of infraspinatus
Supraspinous fossa - origin of supraspinatus
120
Where does serratus anterior originate from and attach to?
Ribs 1-8, attaches to costal surface of scapula
121
Functions of clavicle
Long bone, attaches UL to trunk as part of 'shoulder girdle'
Protects underlying NV structures supplying UL
Transmits force from UL to axial skeleton
122
Parts of clavicle
Sternal (medial) end
Shaft
Acromial end
123
Commonest mechanism of injury for fracture of clavicle
FOOSH or onto the shoulder
Commonest fracture in middle third (80%), followed by lateral and medial
124
What happens to orientation of arm after a clavicle fracture?
Lateral end displaced inferiorly by weight of arm
Displaced medially by pec major
Medial end pulled superiorly by sternocleidomastoid
125
Where does the costoclavicular ligament attach to?
Inferior surface of sternal end of clavicle
126
Which muscles attach to the shaft of clavicle?
```
Trapezius
Deltoid
Subclavius
Pec major
Sternocleidomastoid
Sternohyoid
```
127
Which ligaments attach to the acromial end of clavicle?
Conoid ligament (medial part of coracoclavicular ligament, extrinsic) - attached to conoid tubercle
Trapezoid ligament (lateral part of coracoclavicular ligament, extrinsic) - attached to trapezoid line
Acromioclavicular ligament (intrinsic) - horizontally from acromion to lateral clavicle, covers joint capsule, reinforcing its superior aspect
128
What does the pectoral girdle consist of?
Scapula
| Clavicle
129
Origin of scapula
Extends from 2nd to 7th rib
130
Attachment of clavicle
Attached to 1st rib by costoclavicular ligament
131
Which bone is the first bone to ossify in a fetus?
Clavicle
132
Which is the only long bone to develop in membrane?
Clavicle
133
Which nerves may pierce the clavicle?
Supraclavicular nerves
134
Proximal landmarks of humerus
Head - faces medially, upwards and backwards
Anatomical neck - separates head from greater and lesser tubercles
Surgical neck - runs from just distal to tubercles to shaft of humerus
Greater tubercle
Lesser tubercle
Intertubercular sulcus/bicipital groove - separates the 2 tubercles (edges are called lips)
135
Which muscles attach to the greater tubercle of the humerus?
Supraspinatus
Infraspinatus
Teres minor
136
What muscle attaches to the lesser tubercle of the humerus?
Subscapularis
137
Which muscles insert into the lips of the intertubercular sulcus?
Pec major
Teres major
Lat dorsi
138
Which tendon runs through the intertubercular sulcus?
Long head of biceps brachii
139
Which structures lie against the surgical neck of the humerus?
Axillary nerve - paralysis of deltoid and teres minor
Posterior circumflex artery
140
What attaches to the lateral side of the humeral shaft (deltoid tuberosity)?
Deltoid muscle
141
What is the radial (spiral) groove?
A shallow depression that runs diagonally down the posterior surface of the humerus, parallel to the deltoid tuberosity
142
Which structures lie in the radial groove on the posterior surface of the humerus?
Radial nerve
Pronfunda brachii
(Risk of damage from midshaft humeral fractures)
143
What muscles attach to the anterior surface of humeral shaft?
Deltoid
Brachialis
Brachioradialis
Coracobrachialis
144
What muscles attach to the posterior surface of humeral shaft?
Medial and lateral head of the triceps (spiral groove demarcates their origins)
145
What are the articulations at the elbow joint (distal humerus)?
Capitulum of humerus articulates with head of radius
Trochlea of humerus articulates with trochlear notch of ulna
146
What do the lateral and medial borders of the distal humerus form?
Lateral and medial supracondylar ridges (lateral more roughened, site of common origin of forearm extensors)
147
What passes in a groove on the posterior aspect of the medial epicondyle (distal humerus)?
Ulnar nerve
148
What are the depressions located on the distal humerus?
Coronoid
Radial
Olecranon fossae
Accommodate forearm bones during flexion/extension of elbow
149
Parts of radius
Head
Neck
Radial tuberosity
Shaft
150
What attaches to the radial tuberosity?
Biceps brachii muscle
151
What attaches to the middle of the lateral surface of radial shaft where there is a small roughening?
Pronator teres
152
What parts are found at the distal end of radius?
Styloid process
Ulnar notch - articulates with head of ulna, forming distal radioulnar joint
2 facets for articulation with scaphoid and lunate carpal bones (make up wrist joint)
153
What attaches the radius and ulna together?
Interosseous membrane
154
What is a Monteggia fracture?
Fracture of proximal shaft of ulna + anterior dislocation of head of radius at elbow
155
What is a Galeazzi fracture?
Fracture to the distal radius + dislocation of ulna head at distal radio-ulnar joint
156
Important landmarks of proximal ulna
```
Olecranon
Coronoid process
Trochlear notch
Radial notch
Ulnar tuberosity
```
157
Surfaces of ulnar shaft and their muscle attachments
Anterior - pronator quadratus (distally)
Posterior - many
Medial - unremarkable
158
3 borders of ulnar shaft
Anterior - unremarkable
Interosseous - attachment of interosseous membrane
Posterior - palpable along entire length of forearm posteriorly
159
What muscle attaches to the olecranon of ulna?
Triceps brachii
160
What muscle attaches to the ulnar tuberosity?
Brachialis
161
Carpal bones in order (lateral to medial)
Scaphoid
Lunate
Triquetrum
Pisiform (sesamoid bone, formed within tendon of flexor carpi ulnaris)
Trapezium
Trapezoid
Capitate
Hamate
162
What bones does the radio-carpal joint consist of?
Radius
Scaphoid
Lunate
163
What is a Boxer's fracture?
Fracture of the 5th metacarpal neck, usually caused by clenched fist striking a hard object. Distal part of fracture is displaced anteriorly, producing shortening of affected finger
164
What is a Bennett's fracture?
Fracture of the 1st metacarpal base, caused by forced hyperabduction of the thumb. Fracture extends into 1st MCP joint leading to instability and subluxation of joint.
Hence, often needs surgical repair.
165
Arterial supply to acromioclavicular joint
Suprascapular - from subclavian artery at thyrocervical trunk
Thoracoacromial - from axillary artery
166
Nerve supply of acromioclavicular joint
Articular branches of suprascapular and lateral pectoral nerves - both arise directly from brachial plexus
167
Ligaments of sternoclavicular joint
Sternoclavicular ligaments (anterior and posterior)
Interclavicular ligament - spans gap between sternal ends of each clavicle and reinforces joint capsule superiorly
Costoclavicular ligament - bind at 1st rib and cartilage inferiorly, and to the anterior and posterior borders of clavicle superiorly
168
Arterial supply to sternoclavicular joint
Internal thoracic artery
| Suprascapular artery
169
Nerve supply of sternoclavicular joint
Medial supraclavicular nerve (C3-4)
| Nerve to subclavius (C5-6)
170
Which ligament acts as a pivot for movements of the clavicle?
Coracoclavicular ligament
171
Bursae at glenohumeral (shoulder) joint
Subacromial - located deep to deltoid and acromion, superficial to supraspinatus tendon and joint capsule. Reduces friction beneath deltoid, promoting free motion of rotator cuff tendons.
Subscapular - between subscapularis tendon and scapula, reduces wear and tear at joint
172
Ligaments at shoulder joint
Glenohumeral (superior, middle, inferior)
173
What type of joint is the shoulder (glenohumeral) joint?
Ball and socket - inherently unstable, capable of wide ROM
174
What stabilises the shoulder joint?
Muscles of rotator cuff that pass from scapula to insert into greater tuberosity of humerus (except subscapularis - inserts into lesser tuberosity)
175
What is the glenoid labrum?
A fibrocartilaginous rim attached to the free edge of the glenoid cavity
176
What arises from within the joint from the supraglenoid tubercle?
Tendon of long head of biceps
177
What muscle attaches to the infraglenoid tubercle?
Long head of triceps
178
Attachments of fibrous capsule of shoulder joint
Scapula external to glenoid labrum and to labrum itself (postero-superiorly)
Humerus at level of anatomical neck superiorly and surgical neck inferiorly
179
Relations of fibrous capsule of shoulder joint
Anterior - subscapularis tendon
Superior - supraspinatus tendon
Posterior - infraspinatus and teres minor tendons
180
How many defects are there in the fibrous capsule of shoulder joint
2 defects - superiorly for tendon of biceps, anteriorly defect beneath subscapularis tendon
181
What is the inferior extension of the fibrous capsule of shoulder joint closely related to?
Axillary nerve at surgical neck of humerus, at risk of damage in anteroinferior dislocations
182
Shoulder joint FLEXORS
Anterior deltoid
Pec major
Coracobrachialis
(Biceps)
183
Shoulder joint EXTENSORS
Posterior deltoid
Teres major
Lat dorsi
184
Shoulder joint ADDUCTORS
Pec major
Lat dorsi
(Teres major, coracobrachialis)
185
Shoulder joint ABDUCTORS
Supraspinatus (first 15deg)
| Mid deltoid
186
Shoulder joint MEDIAL ROTATION
```
Subscapularis
Anterior deltoid
Pec major
Teres major
Lat dorsi
```
187
Shoulder joint LATERAL ROTATION
Posterior deltoid
Infraspinatus
Teres minor
188
Important anatomical relations of shoulder joint
Anterior - brachial plexus, axillary artery and vein
Posterior - suprascapular nerve and vessels
Inferior - axillary nerve, circumflex humeral vessels
189
Elbow joint FLEXORS
Biceps
Brachialis
Brachioradialis
(Pronator teres)
190
Elbow joint EXTENSORS
Triceps
| Anconeus
191
Elbow joint PRONATORS
Pronator teres
| Pronator quadratus
192
Elbow joint SUPINATORS
Biceps
| Supinator
193
Root values of ulnar nerve
C8-T1
194
Muscles supplied by ulnar nerve
(No muscles in upper arm)
```
Flexor carpi ulnaris
Flexor digitorum profundus (medial half)
Flexor digiti minimi
Abductor digiti minimi
Opponens digiti minimi
Adductor pollicis
Interossei muscles
3rd and 4th lumbricals
Palmaris brevis
```
195
Path of ulnar nerve
Posteromedial aspect of upper arm to flexor compartment of forearm, then along ulnar
Passes below FCU
Passes superficial to flexor retinaculum into palm
196
Branches of ulnar nerve
```
Muscular branch
Palmar cutaneous branch (arises near middle of forearm)
Dorsal cutaneous branch
Superficial branch
Deep branch
```
197
Areas supplied by branches of ulnar nerve
Muscular - FCU, medial half of FDP
Palmar cutaneous - skin on medial part of palm
Dorsal cutaneous - dorsal surface of medial part of hand
Superficial - cutaneous fibres to anterior surfaces of medial 1.5 digits
Deep - hypothenar muscles, all interossei, 3rd and 4th lumbricals, adductor pollicis, medial head of flexor pollicis brevis
198
Effects of injury to ulnar nerve at wrist
Wasting and paralysis of hypothenar and intrinsic hand muscles (claw hand)
Loss of sensation of medial 1.5 fingers
199
Effects of injury to ulnar nerve at elbow
Radial deviation of wrist
LESS clawing in 4th-5th fingers (as flexor digitorum profundus affected)
200
Branches of thoracoacromial artery
Pectoral
Clavicular
Acromial
Deltoid
201
Path of thoracoacromial artery
Projects forward to upper border of pec minor and pierces coracoclavicular fascia before dividing into its 4 branches
202
Description of pectoral branch of thoracoacromial artery
Descends between 2 pectoral muscles
Distributed to the pectoral muscles and breast
Anastomose with intercostal branches of internal thoracic artery and with lateral thoracic
203
Description of clavicular branch of thoracoacromial artery
Runs upwards and medially to the sternoclavicular joint
Supplies sternoclavicular joint and subclavius
204
Description of acromial branch of thoracoacromial artery
Runs laterally over coracoid process and under the deltoid (to which it gives branches)
Pierces deltoid
Ends on acromion in an arterial network formed by branches from: suprascapular, thoracoacromial, posteriorr circumflex humeral arteries
205
Description of deltoid branch of thoracoacromial artery
Arises with acromial branch
Crosses over pec minor
Passes in same groove as cephalic vein, between pec major and deltoid (giving branches to both muscles)
206
What is the anterior interosseous nerve a branch of?
Median nerve
207
What does the anterior interosseous nerve innervate?
2. 5 muscles (in deep level of anterior compartment of forearm):
- Flexor pollicis longus
- Pronator quadratus
- Radial half of flexor digitorum profundus (lateral 2/4 tendons)
208
Root values of axillary nerve
C5-6
Terminal branch of posterior cord of brachial plexus
209
Path of axillary nerve
Descends posterior to axillary artery at lower border of subscapularis
Passes through quadrangular space with posterior circumflex humeral vessels
Divides into anterior and posterior branches
210
Actions of interossei muscles
Palmar interossei - adduction of fingers
Dorsal interossei - abduction of fingers
PAD DAB
Flexion of MCP joint, extension of PIP and DIP joints (together with lumbricals) - claw hand seen if paralysed (digits pulled into hyperextension)
211
How many interossei muscles are there in total?
4 palmar
4 dorsal
They occupy the spaces between the metacarpal bones
212
Origins and insertions of interossei muscles
Palmar - originates from metacarpal of digit on which it acts
Dorsal - originates from surface of adjacent metacarpal on which it acts (hence 2x the size of palmar)
Interossei tendons (except 1st palmar) pass to one or other side of MCP joint posterior to deep transverse metacarpal ligament. They insert into the base of the proximal phalanx and partly into the extensor hood.
213
Origins of triceps
Long head - infraglenoid tubercle of scapula
Lateral head - dorsal surface of humerus, lateral and proximal to groove of radial nerve
Medial head - posterior surface of humerus on inferomedial side of radial groove and both of the intermuscular septae
214
Insertion of triceps
Olecranon process of ulna
Some fibres insert into deep fascia of forearm, posterior capsule of elbow
215
Nerve supply of triceps
Radial nerve
216
Blood supply of triceps
Profunda brachii
217
Action of triceps
Elbow extension
Note: long head can adduct the humerus and extend it from a flexed position
218
Relations of triceps
Radial nerve and profunda brachii lie between lateral and medial heads
219
Nerve supplies of rotator cuff muscles
Supraspinatus, infraspinatus - suprascapular nerve
Teres minor - axillary nerve
Subscapularis - superior and inferior subscapular nerves
220
Where is the pectoral region located?
Anterior chest wall
221
Muscles of the pectoral region
Pectoralis major
Pectoralis minor
Serratus anterior
Subclavius
222
Parts of pectoralis major
Sternal head
| Clavicular head
223
Attachments of heads of pectoralis major
Clavicular - from anterior surface of medial clavicle
Sternal - from anterior surface of sternum, superior 6 costal cartilages and aponeurosis of external oblique muscle
Both to intertubercular sulcus of humerus
224
Function of pectoralis major
Adduction and medial rotation of UL
Draw scapula anteroinferiorly
Clavicular head acts individually to flex UL
225
Nerve supply of pectoralis major
Lateral and medial pectoral nerves
226
Where does the pectoralis minor lie?
Underneath its larger counterpart, pectoralis major
Both form part of anterior wall of axilla
227
Attachments of pectoralis minor
From ribs 3-5 to coracoid process of scapula
228
Function of pectoralis minor
Stabilise the scapula by drawing it anteroinferiorly against the thoracic wall
229
Nerve supply of pectoralis minor
Medial pectoral nerve
230
Where does the serratus anterior lie?
More laterally in the chest wall
Forms medial border of axilla region
231
Attachments of serratus anterior
Several strips, originate from lateral aspects of ribs 1-8, to costal surface of medial border of scapula
232
Function of serratus anterior
Rotate scapula, allowing arm to be raised >90 degrees
Hold scapula against ribcage
233
Nerve supply of serratus anterior
Long thoracic nerve
234
Where does the subclavius lie?
Directly underneath the clavicle, running horizontally
235
Attachments of subclavius
From junction of 1st rib and its costal cartilage, to inferior surface of middle 3rd of clavicle
236
Function of subclavius
Anchors and depresses the clavicle
237
Nerve supply of subclavius
Nerve to subclavius
238
Groups of muscles of the shoulder
Extrinsic (aka superficial back muscles) - originate from trunk and insert into bnoes of shoulder (clavicle, scapula, humerus)
Intrinsic - originate from scapula/clavicle and attach to humerus
239
Layers of extrinsic muscles of shoulder
Superficial layer
| Deep layer
240
What are the superficial extrinsic muscles of shoulder?
Trapezius (most superficial of all back muscles)
| Latissimus dorsi
241
Attachments of trapezius
Originate from skull, nuchal ligament and spinous processes of C7-12
Attach to clavicle, acromion and scapula spine
242
Innervation of trapezius
Motor - accessory nerve
| Sensory (proprioception) - C3-4 spinal nerves
243
Actions of trapezius
Upper fibres - elevate scapula and rotate it during abduction of arm
Middle fibres - retract scapula
Lower fibres - pull scapula inferiorly
244
What is the commonest cause of accessory nerve damage?
Iatrogenic e.g. cervical LN biopsy, cannulation of internal jugular vein
245
Signs of accessory nerve damage
Inability to shrug shoulders
Muscle wasting
Partial paralysis of SCM
Asymmetrical neckline
246
Attachments of latissimus dorsi
Originate from spinous processes of T7-12, iliac crest, thoracolumbar fascia and inferior 3 ribs
Converge into a tendon that inserts into intertubercular sulcus of humerus
247
Innervation of latissimus dorsi
Thoracodorsal nerve
248
Actions of latissimus dorsi
Extension, adduction, medial rotation of UL
249
What are the deep extrinsic muscles of shoulder?
Levator scapulae
Rhomboid major
Rhomboid minor
250
Attachments of levator scapulae
Originate from transverse processes of C1-4 vertebrae
Attach to medial border of scapila
251
Innervation of levator scapulae
Dorsal scapular nerve
252
Action of levator scapulae
Elevation of scapula
253
Where is the rhomboid minor located in relation to the other deep extrinsic shoulder muscles?
Above rhomboid major, below levator scapulae
254
Attachments of rhomboid major
Originate from spinous processes of T2-5 vertebrae
Attach to medial border of scapula, between scapula spine and inferior angle
255
Innervation of rhomboid major
Dorsal scapular nerve
256
Action of rhomboid major
Retraction and rotation of scapula
257
Attachments of rhomboid minor
Originate from spinous processes of C7-T1 vertebrae
Attach to medial border of scapula, at level of spine of scapula
258
Innervation of rhomboid minor
Dorsal scapular nerve
259
Action of rhomboid minor
Retraction and rotation of scapula
260
What are the intrinsic shoulder muscles also known as?
Scapulohumeral group
261
What are the intrinsic muscles of shoulder?
Deltoid
Teres major
4 rotator cuff muscles
262
Parts of deltoid muscle
Anterior
Middle
Posterior
263
Attachments of deltoid
Originate from lateral 3rd of clavicle, acromion and spine of scapula
Attach to deltoid tuberosity on lateral aspect of humerus
264
Innervation of deltoid
Axillary nerve
265
Actions of deltoid
Anterior fibres - flexion, medial rotation
Posterior fibres - extension, lateral rotation
Middle fibres - abduction
266
Attachments of teres major
Originate from posterior surface of inferior angle of scapula
Attach to medial lip of intertubercular groove of humerus
267
Innervation of teres major
Lower subscapular nerve
268
Actions of teres major
Adduction and extension at shoulder
Medial rotation of arm
269
Attachments of supraspinatus
Originate from supraspinous fossa of scapula
Attach to greater tubercle of humerus
270
Innervation of supraspinatus
Suprascapular nerve
271
Action of supraspinatus
Abduction of arm (1st 15 degree)
272
Attachments of infraspinatus
Originate from infraspinous fossa of scapula
Attach to greater tubercle of humerus
273
Innervation of infraspinatus
Suprascapular nerve
274
Action of infraspinatus
Lateral rotation of arm
275
Attachments of subscapularis
Originate from subscapular fossa, on costal surface of scapula
Attach to lesser tubercle of humerus
276
Innervation of subscapularis
Upper and lower subscapular nerves
277
Action of subscapularis
Medial rotation of arm
278
Attachments of teres minor
Originate from posterior surface of scapula, adjacent to its lateral border
Attach to greater tubercle of humerus
279
Innervation of teres minor
Axillary nerve
280
Action of teres minor
Lateral rotation of arm
281
What is the muscle most commonly affected in rotator cuff tendonitis?
Supraspinatus
During abduction, it 'rubs' against the coracoacromial arch - over time, causes inflammation and degenerative changes in tendon itself
282
Muscles in upper arm
Anterior compartment - biceps brachii, brachialis, coracobrachialis
Posterior compartment - triceps brachii
283
Innervation of muscles in anterior compartment of upper arm
Musculocutaneous nerve
284
Arterial supply to anterior compartment of upper arm
Muscular branches of brachial artery
285
Does the biceps brachii attach to humerus?
No. Although majority of the biceps muscle is located in front of the humerus, it has no attachment to the bone itself
286
What forms the bicipital aponeurosis?
It is a connective tissue sheet that is given off when the tendon of biceps brachii enters the forearm
287
What does the bicipital aponeurosis demarcate?
It forms the roof of the cubital fossa
Blends with deep fascia of anterior forearm
288
Attachments of biceps brachii
Long head originate from supraglenoid tubercle of scapula
Short head originate from coracoid process of scapula
Both heads insert distally into radial tuberosity and fascia of forearm via bicipital aponeurosis
289
Action of biceps brachii
Supination of forearm
Flexion of arm at elbow and shoulder
290
Innervation of biceps brachii
Musculocutaneous nerve
291
What spinal cord segment is the biceps tendon reflex?
C6
292
Where does the coracobrachialis lie in relation to biceps brachii?
Deep to biceps brachii in arm
293
Attachments of coracobrachialis
Originate from coracoid process of scapula
Pass through axilla
Attaches to medial side of humeral shaft at level of deltoid tubercle
294
Action of coracobrachialis
Flexion of arm at shoulder
Weak adduction
295
Innervation of coracobrachialis
Musculocutaneous nerve
296
Where does the brachialis lie in relation to biceps brachii?
Deep to biceps brachii
Found more distally than other arm muscles
Forms floor of cubital fossa
297
Attachments of brachialis
Flexion at elbow
298
Innervation of brachialis
Musculocutaneous nerve
Contributions from radial nerve
299
What sign can you see with rupture of the long head of biceps brachii?
Sign on flexing elbow - bulge where muscle belly is (Popeye sign)
300
Arterial supply to posterior compartment of arm
Profunda brachii
301
Attachments of triceps brachii
Long head - originate from inglenoid tubercle
Lateral head - from humerus, above radial groove
Medial head - from humerus, below radial groove
All converge into 1 tendon distally and insert into olecranon of ulna
302
Function of triceps brachii
Extension of arm at elbow
303
Innervation of triceps brachii
Radial nerve
Note: in some people, long head of triceps tendon is innervated by axillary nerve
304
What spinal cord segment is the triceps tendon reflex?
C7
305
Categories of muscles in anterior compartment of forearm
Superficial
Intermediate
Deep
306
Superficial muscles in anterior compartment of forearm
```
(Medial to lateral)
Flexor carpi ulnaris
Palmaris longus
Flexor carpi radialis
Pronator teres
```
All originate from common tendon arising from medial epicondyle of humerus
307
Attachments of FCU
Originate from medial epicondyle of humerus
Another long origin from ulna
Pass into wrist
Attach to pisiform
308
Action of FCU
Flexion and adduction at wrist
309
Innervation of FCU
Ulnar nerve
310
Attachments of palmaris longus
Originate from medial epicondyle of humerus
Attach to flexor retinaculum
311
Action of palmaris longus
Flexion at wrist
312
Innervation of palmaris longus
Median nerve
313
Attachments of FCR
Originate from medial epicondyle
Attach to base of metacarpals 2 and 3
314
Action of FCR
Flexion and abduction at wrist
315
Innervation of FCR
Median nerve
316
What is the pronator teres a landmark of?
Its lateral border forms the medial border of the cubital fossa
317
Attachments of pronator teres
2 origins: from medial epicondyle and coronoid process of ulna
Attach laterally to midshaft of radius
318
Action of pronator teres
Pronation of arm
319
Innervation of pronator teres
Median nerve
320
Muscles in anterior intermediate compartment of forearm
Flexor digitorum superficialis
| can sometimes be classed as superficial, but lie between deep and superficial layers in most
321
Why is the flexor digitorum superficialis a good anatomical landmark in the forearm?
Median nerve and ulnar artery pass between its 2 heads, then travel posteriorly
322
Attachments of FDS
2 heads - one from medial epicondyle of humerus, and other from radius
Split into 4 tendons at wrist
Travel through carpal tunnel
Attach to middle phalanges of 4 fingers
323
Action of FDS
Flexion of MCP and PIP joints at 4 fingers
Flexion at wrist
324
Innervation of FDS
Median nerve
325
Muscles in deep anterior compartment of forearm
Flexor digitorum profundus
Flexor pollicis longus
Pronator quadratus
326
Attachments of FDP
Originate from ulna and associated interosseous membrane
Split into 4 tendons at wrist
Travel through carpal tunnel
Attach to distal phalanges of 4 fingers
327
Action of FDP
Only muscle that can flex DIP joints of fingers
Flexion of MCP joints and wrist
328
Innervation of FDP
Medial half by ulnar nerve
Lateral half by anterior interosseous branch of median nerve
329
Where is the flexor pollicis longus in relation to the FDP?
Lateral to FDP
330
Attachments of FPL
Originate from anterior surface of radius and surrounding interosseous membrane
Attach to base of distal phalanx of thumb
331
Action of FPL
Flexion of MCP and IP joints of thumb
332
Innervation of FPL
Anterior interosseous branch of median nerve
333
Where is the pronator quadratus in relation to the FDP and FPL?
Square-shaped muscle deep to tendons of FDP and FPL
334
Attachments of pronator quadratus
Originate from anterior surface of ulna
Attach to anterior surface of radius
335
Action of pronator quadratus
Pronation of forearm
336
Innervation of pronator quadratus
Anterior interosseous branch of median nerve
337
Layers of posterior compartment of forearm
Superficial
Deep
Both layers separated by a layer of fascia
338
Superficial muscles in posterior compartment of forearm
```
Brachioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor digitorum communis
Extensor digiti minimi
Extensor carpi ulnaris
Anconeus
```
Radialis brevis, ulnaris, digitorum communis and digiti mini share a common tendinous origin at lateral epicondyle of humerus
339
Why is the brachioradialis a paradoxical muscle?
Its origin and innervation are characteristic of an extensor muscle
It's actually a flexor at the elbow
340
When is the brachioradialis muscle most visible?
When forearm is half-pronated, and flexing at elbow against resistance
341
Attachments of brachioradialis
Originate from proximal aspect of lateral supracondylar ridge of humerus
Attach to distal end of radius, just before styloid process
342
Action of brachioradialis
Flexion at elbow
343
Innervation of brachioradialis
Radial nerve
344
Attachments of extensor carpi radialis longus and brevis
ECRL originate from supracondylar ridge
ECRB originate from lateral epicondyle
Tendons attach to metacarpal bones 2 and 3
345
Action of of extensor carpi radialis longus and brevis
Extension and abduction at wrist
346
Innervation of extensor carpi radialis longus and brevis
Radial nerve
347
Which muscle the main extensor of fingers?
Extensor digitorum communis
348
Attachments of extensor digitorum communis
Originate from lateral epicondyle
Continue into distal part of forearm, where it splits into 4
Insert into extensor hood of each finger
349
Action of extensor digitorum communis
Extension of fingers at MCP and IP joints
350
Innervation of extensor digitorum communis
Deep branch of radial nerve
351
Anatomically, where does the extensor digiti minimi lie?
Medial to extensor digitorum
352
Attachments of extensor digiti minimi
Originate from lateral epicondyle of humerus
Attach into extensor hood of fingers with extensor digitorum tendon
353
Action of extensor digiti minimi
Extension of little finger
Contribute to extension at wrist
354
Innervation of extensor digiti minimi
Deep branch of radial nerve
355
Attachments of ECU
Originate from lateral epicondyle of humerus
Attach to base of metacarpal 5
356
Action of ECU
Extension and adduction of wrist
357
Innervation of ECU
Deep branch of radial nerve
358
Where is the anconeus located in the extensor compartment of forearm?
Superiorly and medially
Blended with fibres of triceps brachii (the 2 can be indistinguishable)
359
Action of anconeus
Extension and stabilisation of elbow
Abduction of ulna during forearm pronation
360
Innervation of anconeus
Radial nerve
361
Muscles in deep compartment of posterior forearm
```
Supinator
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
Extensor indicis
```
362
Where does the supinator lie in the deep posterior compartment of forearm?
In the floor of cubital fossa
363
How many heads does the supinator have and what passes in between them?
2 hears with deep branch of radial nerve passing in between
364
Attachments of supinator
1 head from lateral epicondyle of humerus, other from posterior surface of ulna
Attach together to posterior surface of radius
365
Action of supinator
Supination of forearm
366
Innervation of supinator
Deep branch of radial nerve
367
Where is the abductor pollicis longus located in relation to the supinator?
Immediately distal to supinator
368
Attachments of APL
Originate from interosseous membrane and adjacent posterior surfaces of radius and ulna
Attaches to lateral side of base of metacarpal 1
369
Action of APL
Abduction of thumb
370
Innervation of APL
Posterior interosseous branch of radial nerve
371
Where is the extensor pollicis brevis located in relation to the APL?
Medial and deep to the abductor pollicis longus
372
Attachments of EPB
Originate from posterior surface of radius and interosseous membrane
Attach to base of proximal phalanx of thumb
373
Innervation of EPB and EPL
Posterior interosseous branch of radial nerve
374
Attachments of EPL
Originate from posterior surface of ulna and interosseous membrane
Attach to distal phalanx of thumb
375
Action of EPB
Extension at MCP and CMC joints of thumb
376
Action of EPL
Extension of all thumb joints: CMC, MCP, IP joints
377
What makes the extensor indicis propius unique?
It allows the index finger to be independent of other fingers during extension
378
Attachments of extensor indicis propius
Originate from posterior surface of ulna and interosseous membrane, distal to EPL
Attach to extensor hood of index finger
379
Action of extensor indicis propius
Extension of index finger
380
Innervation of extensor indicis propius
Posterior interosseous branch of radial nerve
381
What is wrist drop a sign of?
Radial nerve injury proximal to elbow
382
What are the 2 common characteristic sites of damage of radial nerve?
Axilla - injured via humeral dislocations or fractures of proximal humerus
Radial groove of humerus - injured via humeral shaft fracture
383
Groups of muscles acting on the hand
Extrinsic - located in anterior and posterior compartments of forearm, control crude movements and produce forceful grip
Intrinsic - located within hand itself, for fine motor functions
384
Nerve roots of axillary nerve
C5-6
385
Sensory function of axillary nerve
Gives rise to upper lateral cutaneous nerve of arm
Innervate skin over lower deltoid ('regimental badge area')
386
Motor function of axillary nerve
Deltoid
| Teres minor
387
Anatomical course of axillary nerve
Direct continuation of posterior cord of brachial plexus
In axilla - posterior to axillary artery and anterior to subscapularis
Exits axilla at inferior border of subscapularis via quadrangular space
Pass medial to surgical neck of humerus
388
What happens to the axillary nerve at the surgical neck of humerus?
Divides into 3 branches:
1. Posterior terminal branch
2. Anterior terminal branch
3. Articular branch
389
Function of posterior terminal branch of axillary nerve
Motor innervation to posterior aspect of deltoid and teres minor
Sensory innervation to skin over inferior part of deltoid
390
Function of anterior terminal branch of axillary nerve
Motor innervation to anterior part of deltoid
Terminates with cutaneous branches to anterior and anterolateral shoulder
391
Function of articular branch of axillary nerve
Supplies glenohumeral joint
392
What is the quadrangular space?
A gap in the muscles of the posterior scapular region
Pathway for NV structures to move from axilla anteriorly to posterior shoulder and arm
393
Boundaries of quadrangular space
Superior - inferior border of teres minor
Inferior - superior border of teres major
Lateral - surgical neck of humerus
Medial - long head of triceps brachii
Anterior - subscapularis
394
What happens after the posterior terminal branch of axillary artery has innervated the teres minor?
It continues as the upper lateral cutaneous nerve of arm
395
What is Erb's palsy?
A condition due to damage from C5-6 roots
Axillary nerve is affected, person unable to abduct or externally rotate shoulder joint
396
Nerve roots of musculocutaneous nerve
C5-7
397
Motor function of musculocutaneous nerve
Muscles in anterior compartment of upper arm (biceps, brachialis, coracobrachialis)
398
Sensory function of musculocutaneous nerve
Gives rise to lateral cutaneous nerve of forearm which innervates lateral aspect of forearm
