My upper limb (fuck) Flashcards

1
Q

Where does the clavicle articulate with the scapula?

A

acromion of the scapula at its lateral end (the acromioclavicular joint) –

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2
Q

What do The clavicle, scapula and the attached muscles comprise?

A

The pectoral girdle

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3
Q

What are the movements of the scapula

A

Protraction - this extends the upper limb, for example, when we stretch out the
arm to push open a door.
Retraction - ‘squaring’ the shoulders
Elevation - shrugging the shoulders
Depression – lowering the shoulders
Rotation - this tilts the glenoid fossa cranially to aid elevation of the upper limb

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4
Q

What are the two large superficial muscles of the pectoral girdle

A

Trapezius
 Latissimus dorsi

These are large, flat muscles with extensive attachments to the vertebral column

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5
Q

What are the 3 smaller, deeper muscles of the pectoral girdle
Where do they attatch

A

 Levator scapulae
 Rhomboid major
 Rhomboid minor

attach the medial border of the scapula to the vertebral column.

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6
Q

Where does the Latissimus dorsi insert

A

the humerus

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7
Q

What is the action of the trapezius on the scapula?

A

Upper part: elevates. Middle part: retracts.

Lower part: depresses. Rotates the scapula.

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8
Q

What is the action of the Levator scapulae on the scapula?

A

elevates, and rotates

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9
Q

What is the action of the Rhomboid major and minor on the scapula?

A

retracts

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10
Q

What is the action of the lattismus dorsi on the humerus

A

Extends, adducts and medially rotates the humerus

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11
Q

What is the trapezius innervated by

A

the 11th

cranial nerve; the accessory nerve (spinal root)

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12
Q

What is the lattisums dorsi innervated by

A

a branch of the brachial plexus called the

thoracodorsal nerve

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13
Q

What are teh 6 muscles that attatch the scapula to the humerus?

A

Deltoid
 Teres major

 Supraspinatus
 Infraspinatus
 Subscapularis
 Teres minor

Bottom four are rotator cuff muscles

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14
Q

What is the large muscle over the lateral aspect of the shoulder?

What does it attacth the humerus to?
Where does attatch on the scapula?

A

The Deltoid It attaches the
humerus to the lateral part of the clavicle and to the spine of the scapula

It inserts onto the humerus at a landmark called the deltoid tuberosity

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15
Q

What is the action of the deltoid?

What do the anterior and posterior fibres of this muscle do?

A

It is a powerful abductor of the shoulder joint. However, deltoid cannot initiate
abduction – another muscle (subscapularis) initiates the first 20 degrees (or so) of abduction before deltoid takes over

the anterior and posterior fibres of deltoid
contribute to flexion and extension of the shoulder, respectively.

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16
Q

What is the innervation of the deltoid

A

the axillary nerve

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17
Q

Where does the teres major originate and insert?

How does this explain its action

A

Teres major is an interesting muscle as although it arises from the posterior aspect
of the scapula, it inserts onto the anterior aspect of the humerus. This arrangement
explains its action as a medial rotator and adductor of the shoulder joint

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18
Q

Where do the 4 rotator cuffs origate from ?

A

from the posterior

surface of the scapula and insert onto the greater tubercle.

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19
Q

What is the quadrilateral space? what travels through it?

A

This is a square-shaped
space bounded by: teres minor above, teres major below, the long head of triceps
medially and the surgical neck of the humerus laterally. The axillary nerve travels
through this space to enter the posterior scapula region and innervate deltoid
and teres minor.

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20
Q

What rotor cuff muslces laterally rotate?

A

Teh infraspinatus and teres minor

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21
Q

What is the action of the supraspinatus ?

A

first 20 degress of abduction

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22
Q

What is the action of the subscapularis?

It is the anterior rotator cuff

A

Medial rotation

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23
Q

How many muscles are there in the posterior upper arm?

Where does it insert?

A

1 - the triceps brachii

– the olecranon of the ulna

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24
Q

What are the 3 origins of the 3 heads of the tricpes?

A

Long head: infraglenoid tubercle of the scapula. It is the most medial part of
triceps.
 Lateral head: posterior humerus, proximal to the radial groove.
 Medial head: posterior humerus, distal to the radial groove

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25
Q

What is the action of the triceps?

What is it innervated by

A

Extends the elbow
Because of its attachment to the scapula, the long head is able to contribute to
extension of the shoulder joint

all innervated by radial nerve

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26
Q

What is the axilla?

A

The axilla is the anatomical term for the armpit – the space between the trunk and the
upper arm.

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27
Q

What makes up the :

Anterior wall
Posterior wall
Apex
base

of the Axilla?

A

Anterior wall – pectoralis major and minor
 Posterior wall – subscapularis, teres major and latissiumus dorsi
 Apex – first rib, clavicle and scapula. It is the passage between the neck and the
axilla
 Base – skin and fascia between the chest wall and arm

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28
Q

Where does the axillary artery become the brachial artery ?

A

As it crosses the inferior border of teres major

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29
Q

What are the trunks of the brachial plexus:

A

C5 and C6 combine to form the superior trunk
 C7 continues as the middle trunk
 C8 and T1 combine to form the inferior trunk

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30
Q

Just learn the brachail plexus dickhead

A

seriously.

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31
Q

What does the axillary nerve innervate?

A

It innervates deltoid and teres

minor and a small region of skin over the upper lateral arm.

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32
Q

What does the Radial nerve innervate?

A

The radial nerve innervates
triceps in the posterior arm. The radial nerve also innervates all the muscles in the
posterior compartment of the forearm – these muscles are extensors of the wrist
and digits. The radial nerve also innervates regions of skin over the arm, forearm and
hand.

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33
Q

What does the musculocutaneous nerve innervate?

A

the three muscles in the anterior arm

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34
Q

What does the median nerve innervate ?

A

es most of the muscles of the anterior forearm, which are flexors
of the wrist and digits.

Innervates the small muscles of the thumb
It innervates skin over the
lateral aspect of the palm of the hand and over the lateral digits

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35
Q

What does the ulnar nerve innervate ?

A

It contains fibres from spinal nerves C8 - T1.
 It innervates most of the small muscles in the hand and therefore is vital for
fine movements of the digits.
 It also innervates skin over the medial aspect of the hand and medial digits

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36
Q

what are the 3 muscles of the anterior forearm, and what are they innervated by?
What is their action

A

biceps brachii,
brachialis and coracobrachialis.
 All three act as flexors
 All three are innervated by the musculocutaneous nerve.

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37
Q

What is the most superficial anterior arm muscle?

A

The biceps brachii

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38
Q

What do the coracobrachialis and the short head of biceps brachii insert onto?

A

The coracoid process

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39
Q

Where is the cubital fossa?

What are its contents?

A

The region anterior to the elbow joint

Really Need (radial nerve) Beer To (biceps tendon) Be At (brachial artery) My Nicest (median nerve).

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40
Q

What is the superficial nerve that travels behind the medial epicondyle?

A

The ulnar nerve - it is prone to injury

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41
Q

How do the radius and ulnar articulate with the humerus

A

the trochlea notch of the ulna articulates with the trochlea of the
humerus and the radial head articulates with the capitellum of the humerus.

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42
Q

What are the four muscles lateral to medial on the superficial layer of the anterior wrist?

Where do they attach?

A

Pronator teres
 Flexor carpi radialis
 Palmaris longus
 Flexor carpi ulnaris

The medial epicondyle

Brachioradialis comes over on the lateral side, but it is not one of the 4, as it does not insert on the medial epicondyle

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43
Q

What are the four muscles supericidal and anterior innervated by?

A

Pronator teres
Flexor carpi radialis
Palmaris longus
These 3 are innervated by the median nerve (the general rule)

Flexor carpi ulnaris is innervated by the ulnar nerve

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44
Q

What is the one muscle in the middle layer of the anterior part of the hand?
What is its innervation

A

flexor digitorum superficialis

The Median nerve

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45
Q

What are the 3 muscles of the deep layer of the anterior arm?
Describe their layout

A

Flexor pollicis longus is on the lateral side
Flexor Digitorum profundus is bigger, and more medial
The pronator quadratus is squared shaped and

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46
Q

what are the 3 muscles of the deep anterior arm?

A

Flexor pollicis longus
Flexor Digitorum profundus
pronator quadratus

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47
Q

what is the innervation of Flexor digitorum proundus

A

The lateral half of the muscle, which gives rise to the tendons that travel to the
index and middle fingers, is innervated by the median nerve.
The medial half of the muscle, which gives rise to the tendons that travel to the
ring and little fingers, is innervated by the ulnar nerve

48
Q

What is the innervation of the Flexor Pollicis longus, and pronator quadratus

A

the median nerve,

49
Q

What is the carpal tunnel? what forms its base and its roof?

A

The carpal tunnel is a narrow passageway at the wrist.
Its floor and sides are formed by the carpal bones.
A fibrous band called the flexor retinaculum completes the tunnel, forming the roof

50
Q

What travels through the carpal tunnel?

A

The tendons of the anterior forearm muscles that insert into the digits travel
through the carpal tunnel. These are the tendons of:
 flexor digitorum superficialis (4 tendons, to digits 2-5)
 flexor digitorum profundus (4 tendons, to digits 2-5)
 flexor pollicis longus (1 tendon, to the thumb [1st digit])
The median nerve also travels through the carpal tunnel

51
Q

what would A patient with carpal tunnel syndrome typically presents with?

A

impaired or altered sensation over the skin of the hand supplied by the median
nerve - the patient may experience tingling, numbness or pain in the hand.
weakness of the hand muscles supplied by the median nerve – particularly the
small muscles of the thumb

52
Q

Where does the brachial artery bifurcate and what into?

A

The brachial artery bifurcates in the cubital fossa into two terminal branches – the
radial artery and the ulnar artery.

53
Q

What are the 2 superficial veins of the wrist? what is where?

A

The cephalic vein courses laterally in the forearm and the basilic vein courses
medially

54
Q

Briefly describe venous drainage up the arm

A

Starts with - Cephalic vein on the Thumb /Lateral side and Basilic vein on the Medial/Pinkie side, ==> Join to from the Axillary Vein at the Antecubital Fossa, ==> Subclavian vein ==> Internal Jugular vein ==> SVC

55
Q

What is the cause of carpal tunnel syndrome?

A

Swelling of the tendons increases the pressure in the tunnel and compresses on the median nerve.

56
Q

What are the 8 carpal bones

nmonic - 2 rows of 4, both starting from/with scaphoid

A

right hand:

hamate, Capitate, Trapezoid, trapezium
Pisiform, Triquetrum, lunate, Scaphoid

57
Q

What is the name of the joint between the
a distal row of carpal bones
and the proximal parts (the bases) of the metacarpals
b between the phalanges
c between the distal parts (the heads)
of the metacarpals and the proximal phalanges

A

a Carpometacarpal
b Interphalangeal #
c – lie between the distal parts (the heads)
of the metacarpals and the proximal phalanges

58
Q

What are teh muscles of teh anterior forearm that are prime flexors of the wrist?

A

Flexor carpi radialis - inserts onto the 2nd metacarpal
 Flexor carpi ulnaris - inserts onto the 5th metacarpal
 Palmaris longus (if present) - inserts into the palmar fascia

59
Q

What is the only muscle that can flex the thumb at the interphalangeal joint?

A

The tendon of flexor pollicis longus (FPL) inserts onto the distal phalanx of the
thumb.

60
Q

What is the only muscle capable of flexing the Distal interphalangeal joint?

A

The tendon of flexor digitorum profundus,

o insert onto the palmar aspect of the distal phalanx of digits 2-5

61
Q

Where does the flexor digitorum superficialis insert?

A

it splits into two slips which

insert on either side of the middle phalanx of digits 2-5.

62
Q

what are the four intrinsic muscle groups of the hand?

A

thenar eminence – contains three muscles
hypothenar eminence – contains three muscles
lumbricals – there are four
interossei – there are seven

63
Q

Where is and what is the thenar eminence?

What are they all innervated by?

A

This is the fleshy mass on the palm of the hand at the base of the thumb. It contains
three muscles that act upon the thumb:

Flexor pollicis brevis (FPB) - flexes the thumb
 Abductor pollicis brevis (APB) - abducts the thumb
 Opponens pollicis - (OP) - opposes the thumb

All innervated by branch of median nerve

64
Q

What is most superfical thenar muscle?
What is the most lateral?
What is the most medial?

What are they all innervated by?

A

Abductor pollicis brevis
opponens polllicis is most lateral
flexor pollicis brevis is most medial

All innervated by branch of median nerve

65
Q

What are all the thenar muscles attached/origante from?

A

the carpal bones proximally.

66
Q

Where is and what is the hyperthenar eminence?

What are they all innervated by?

A

is the fleshy mass on the medial side of the palm of the hand, proximal to the
little finger. It contains three small muscles that act upon the little finger:
 Flexor digiti minimi (FDM) - flexes the little finger
 Abductor digiti minimi (ADM) - abducts the little finger
 Opponens digiti minimi (ODM) - opposes the little finger

Their name dictates their actions

67
Q

What is the arrangement of the hyper thenar muscles?

Deep, lateral, medial

A

opponens digiti mini is the deepest
Abductor digiti minimi is most lateral
Flexor digiti minimi is most medial

68
Q

What are the lumbricals? Where do they arise and insert?

What are their innervation?

A

arise from the tendons of flexor digitorum profundus
 travel along the lateral aspects of digits 2-5
 insert onto the dorsal aspects of digits 2-5

The innervation of the lumbricals follows that of the FDP tendons from which they
arise:
==> the lateral two (digits 2 and 3) are innervated by the median nerve
==> the medial two (digits 4 and 5) are innervated by the ulnar nerve

69
Q

What is the action of the lumbricals?

What are their innervation?

A

They flex the MCP joints and
simultaneously extend the IP joints.

The innervation of the lumbricals follows that of the FDP tendons from which they
arise:
==> the lateral two (digits 2 and 3) are innervated by the median nerve
==> the medial two (digits 4 and 5) are innervated by the ulnar nerve

70
Q

What are the Interossei?

What is their action?

A

These muscles are attached to and lie between the metacarpals. There are two
groups; a palmar group and a dorsal group

The palmar interossei adduct the fingers (towards the middle finger)
 The dorsal interossei abduct the fingers (away from the middle finger)

 This can be remembered by PAD-DAB (Palmar ADduct, Dorsal ABduct).
 The interossei contribute to extension of the fingers at the IP joints.

71
Q

How many muscles in the palmar interossei group? How many in the dorsal interossei?

A

3 in palmar, 4 in dorsal

 This can be remembered by PAD-DAB (Palmar ADduct, Dorsal ABduct).
 The interossei contribute to extension of the fingers at the IP joints.

72
Q

What are both the interrossei muscles innervated by?

A

the ulnar nerve

73
Q

Where does the median nerve supply sensation to on the hand

A

the palmar surface of the lateral side of the hand. The palmar surface of
the lateral 3 ½ digits

74
Q

Where does the Ulnar nerve supply sensation to on the hand

A

: the palmar and dorsal surfaces of the medial side of the hand and the medial
1 ½ digits

75
Q

Where does the Radial nerve supply sensation to on the hand

A

: the dorsal surface of the lateral side of the hand. The skin over the dorsum
of the lateral 3 ½ digits as far as the DIP joint.

76
Q

What is the dermatome for the thumb and lateral arm

A

C6

77
Q

What is the dermatome for the pinkie side and medial lower arm

A

C8

78
Q

What arteries does the brachial artery branch into?

A

The radial and ulnar arteries.

79
Q

What arteries form the superficial palmar arch?

A

The ulnar artery and a small contribution from the radial artery.

80
Q

What artery mainly provides the Deep perfusion of the palm of the hand?

A

The radial artery

81
Q

What are the 6 superficial posterior lower arm muscles (lateral to medial)

Where are these generally attached to?

A
 Brachioradialis
 Extensor carpi radialis longus 
 Extensor carpi radialis brevis 
 Extensor digitorum
 Extensor digiti minimi
 Extensor carpi ulnaris

the lateral epicondyle of
the humerus – otherwise known as the ‘common extensor origin’.

82
Q

How many layers of posterior lower arm muscles are there? Where are these generally attached to?

A

2 - superficial and deep

the lateral epicondyle of
the humerus – otherwise known as the ‘common extensor origin’.

83
Q

What is the abnomianlly in the posterior compartment? Why and where does it insert?
what is its action and innervation

A

BRACHORADIALIS

It originates from the humerus, proximal to the lateral epicondyle, and inserts on the
distal radius. It acts as a weak flexor of the elbow joint and hence functions as an
anterior compartment muscle. However, it is innervated by the radial nerve

84
Q

What are the actions and insertions of Extensor carpi radialis longus, and Extensor carpi radialis brevis?

What are they innervated by

A

lie on the radial side of
the posterior compartment. ECRL inserts onto the 2nd metacarpal and ECRB inserts
onto the 3rd metacarpal,
hence they extend and abduct the wrist

Radial nerve!!

85
Q

What is the most medial of the superfical posterior arm muscles?
What is its action and insertion

What are they innervated by

A

Extensor carpi ulnaris
. It
extends and adducts the wrist via its insertion onto the 5th metacarpal.
Radial nerve

86
Q

What do the tendons of the posterior muscles travel under? What is the significance of this?

A

extensor retinaculum. It prevents the tendons from bowing when the wrist is
extended.

87
Q

what are the 5 muscles in the deep part of the posterior forearm?
Lateral to medial

A
Supinator (Finishes v short up the arm )
 Abductor pollicis longus
 Extensor pollicis brevis
 Extensor pollicis longus
 Extensor indicis

note the 3 thumb ones in the middle and brevis in the crevice again

88
Q

What are the 2 deep muscles of the posterior forearm that are not extensors? What is their action instead?

A

 Supinator supinates the forearm and hand

 Abductor pollicis longus abducts the thumb. It inserts on the 1st metacarpal

89
Q

What are the actions of
 Extensor pollicis brevis
 Extensor pollicis longus

A

Extensor pollicis brevis (EPB) and extensor pollicis longus (EPL) extend the
thumb. EPB inserts on the proximal phalanx, so extends the MCP joint. EPL inserts on
the distal phalanx, so is the only muscle capable of extending the interphalangeal joint
of the thumb.

90
Q

Summarise actions of the 5 posterior foremarm

A

extensors, except for brachioradialis, supinator and abductor pollicis longus
 innervated by the radial nerve
The muscles that cross the wrist also contribute to wrist extension.

91
Q

What are the 4 muscles on the dorsum of the hand?

A

The dorsal interossei -

92
Q

what is the action of the dorsal interossei

A

Abduct the fingers at the MCP joint

93
Q

What are the boarders of the anatomical snuffbox?

A

The boundaries of the snuffbox are the tendon of Extensor Pollicis Longus medially and the tendons of
Extensor Pollicis Brevis and Abductor Pollicus Longus laterally

94
Q

Why is the anatomical snuff box clinically important?

A

The scaphoid lies in the floor of the ASB. ASB tenderness on palpation may
indicate a scaphoid fracture
 The radial artery travels through it
 The cephalic vein arises in the ASB; it can be cannulated here if necessary

95
Q

What is the posterior compartment arm muscles suppled by ?

A

the ulnar artery. This artery is

accompanied by deep veins.

96
Q

What muscles protract (shoulders forward) the scapula?

A

Serratus anterior

97
Q

What muscles Retract (shoulders backwards) the scapula?

A

Rhomboids, trapezius

98
Q

What muscles depress the scapula?

A

trapezius

99
Q

What muscles rotate the scapula?

A

trapezius

100
Q

What muscles bring about flexion at the shoulder joint?

A

Anterior fibres of deltoid, biceps brachii,

coracobrachiali

101
Q

What muscles bring about extension at the shoulder joint?

A

Posterior fibres of deltoid, latissimus dorsi,

triceps (long head)

102
Q

What muscles bring about abduction at the shoulder joint?

A

Supraspinatus – first 20 degrees, deltoid

103
Q

What muscles bring about adduction at the shoulder joint?

A

Pectoralis major, latissimus dorsi, teres major

104
Q

What muscles bring about lateral rotation at the shoulder joint?

A

Infraspinatus, teres minor

105
Q

What muscles bring about medial rotation at the shoulder joint?

A

Subscapularis, teres major, latissimus dorsi

106
Q

What muscles bring flexion at the wrist joint?

A

Flexor carpi radialis and ulnaris, palmaris longus.

FDP, FDS and FPL contribute

107
Q

What muscles bring extension at the wrist joint?

A

Extensor carpi radialis longus and brevis, extensor carpi

ulnaris, extensor digitorum.

108
Q

What muscles bring abduction at the wrist joint?

A

Flexor carpi radialis, extensor carpi radialis longus and
brevis

(lateral side, outwards)

109
Q

What muscles bring adduction at the wrist joint?

A

Flexor carpi ulnaris, extensor carpi ulnaris.

medial side, back in!

110
Q

What 3 muscles attatch to the coracoid process?

A

the pectoralis minor, coracobrachialis, and the short head of the biceps brachii.

111
Q

What is anterior and what is posterior to each other - the coracoid process and`e acromion?

A

The acromion is at the back and a bit higher up compared to the coracoid process

112
Q

Where does the humerous articulate with the scapula?

A

Glenohumeral joint – between the glenoid fossa of the scapula and the head of the humerus.

At the glenoid fossa!

113
Q

What muscle is responsible for winging of the scapula?

A

due a lesion in the long thoracic nerve (a branch C 5, 6 and 7
nerve roots) which causes damage to the serratus anterior muscle.

114
Q

What is the action of pec major? What is it innervated by

A

medially rotates the upper limb.
Think about the attachment (intertubercular sulcus),

innervated by lateral and medial pectoral nerves (root value C5-T1), which stem from the brachial plexus.

115
Q

where does the tricep brachii insert on?

A

Olecranon. The olecranon has 4 sites of attachment (three of origin and one of
insertion)