Anatomy: Upper Limb (Dissection) Flashcards
what muscles make up the anterior compartment of the arm?
biceps brachii
coracobrachialis
brachialis
what nerve innervates the muscles of the anterior compartment of the arm?
musculocutaneous nerve
describe the biceps brachii
comprises a long head, a short head and two distal tendons
what are the two distal tendons of the biceps brachii?
biceps tendon
bicipital aponeurosis
what is the most anterior muscles of the anterior compartment of the arm?
the biceps brachii
where is the proximal attachment of the long head biceps brachii?
supraglenoid tubercle of the scapula
where is the proximal attachment of the short head biceps brachii?
coracoid process of the scapula
what muscles attach to the coracoid process?
pectoralis minor
coracobrachialis
short head biceps brachii
where does the biceps tendon insert?
radial tuberosity
where does the bicipital aponeurosis insert?
blends with the antebrachial fascia on the medial side of the proximal forearm
where is the proximal attachment of coracobrachialis?
the coracoid process of the scapula
where is the distal attachment of coracobrachialis?
the humerus
where does coracobrachialis lie in the anterior compartment of the arm?
deep to biceps brachii
medial to brachialis
what separates the coracobrachialis from the triceps?
the medial intermuscular septa
where is the proximal attachment of brachialis?
the humerus
where is the distal attachment of brachialis?
the coronoid process of the ulna
where does brachialis lie in the anterior compartment of the arm?
deep to biceps brachii
lateral to coracobrachialis
what separates brachialis from the triceps?
the lateral intermuscular septae
what joints do all three muscles of the anterior compartment of the arm span?
the shoulder
the elbow
what are the main movements of the anterior compartment of the arm?
flexion at the shoulder
flexion at the elbow
what movement can biceps brachii do and how?
supination
spans the proximal radioulnar joint
what nerve innervates most of the muscles of the anterior compartment of the forearm?
median nerve
which two muscles are not supplied by the median nerve in the anterior compartment of the forearm, and which nerve supplies them?
flexor carpi ulnaris
medial part of the flexor digitorum profundus
the ulnar nerve
what movements are caused by the muscles of the anterior compartment of the forearm?
flexion, abduction and adduction of the wrist
flexion of the digits
pronation of the forearm
how many layers make up the anterior compartment of the forearm?
three
what are the layers of the anterior compartment of the forearm?
superficial
intermediate
deep
what is the tendon of the superficial layer of the anterior compartment of the forearm called?
the common flexor tendon
where does the common flexor tendon insert?
the medial epicondyle of the humerus
what muscles make up the superficial layer of the anterior compartment of the forearm?
pronator teres
palmaris longus
flexor carpi radialis
flexor carpi ulnaris
where is the distal attachment of palmaris longus?
the palmar aponeurosis
where is the distal attachment of flexor carpi radialis?
the metacarpals on the radial side
where is the distal attachment of flexor carpi ulnaris?
the metacarpals on the ulnar side
where does the muscle of the intermediate layer of the anterior compartment of the forearm attach proximally?
medial epicondyle of the humerus
the coronoid process of the ulna
the radial head
what muscle makes up the intermediate layer of the anterior compartment of the forearm?
flexor digitorum superficialis
describe the structure of flexor digitorum superficialis
four muscle bellies
four tendons for the medial four digits
where do the muscles of the deep layer of the anterior compartment of the forearm attach proximally?
to the anterior surface of either the radius or the ulna
what muscles make up the deep layer of the anterior compartment of the forearm?
flexor digitorum profundus
flexor pollicis longus
pronator quadratus
where is the distal attachment of flexor digitorum profundus?
digits 2-5
where is the distal attachment of flexor pollicis longus?
the thumb
where is the distal attachment of pronator quadratus?
between distal anterior surfaces of the radius and the ulna
what is the superior boundary of the cubital fossa?
transverse line between the epicondyles of the humerus
what is the medial border of the cubital fossa?
pronator teres
what is the lateral border of the cubital fossa?
brachioradialis
what are the superficial contents of the cubital fossa?
median cubital vein
cephalic vein
basilic vein
tendons of biceps brachii
what are the deep contents of the cubital fossa, from medial to lateral?
median nerve
brachial artery
radial nerve
what is the axilla?
the space inferior to the shoulder joint and superior to the armpit
what is the medial wall of the axilla?
the superolateral aspect of the chest
what forms the anterior wall of the axilla?
pectoralis major
where is the lower border of pectoralis major contained?
within the inferior edge of the anterior axillary fold
what are the main muscles of climbing?
pectoralis major
latissimus dorsi
what is the superior continuation of the brachial vein?
the axillary vein
where does the brachial vein become the axillary vein?
at the lower border of the teres major
what makes up part of the posterior wall of the axilla?
teres major
what does the inferior border of teres major correspond with?
the inferior extent of the axilla
where can the pulsations of the subclavian artery be palpated?
where the artery crosses the first rib
where does the subclavian artery become the axillary artery?
at the lateral border of the first rib
what provides nerve supply to the upper limbs?
the brachial plexus
what forms the brachial plexus?
intertwined anterior rami of spinal nerves C5-T1
what are the main parts of the brachial plexus, from proximal to distal?
roots trunks divisions cords named nerves
what are the roots of the brachial plexus?
the anterior rami of C5-T1 spinal nerves
what forms the trunks of the brachial plexus?
combination of the nerve fibres of the roots
what are the trunks of the brachial plexus?
superior
middle
inferior
what makes up the superior trunk of the brachial plexus?
combined anterior rami of C5 and C6 spinal nerves
what makes up the middle trunk of the the brachial plexus?
anterior ramus of C7 spinal nerve
what makes up the inferior trunk of the brachial plexus?
combined anterior rami of C8 and T1 spinal nerves
what do the trunks of the brachial plexus divide into?
anterior and posterior divisions
what do the divisions of the brachial plexus combine to form?
the cords
what are the cords of the brachial plexus named according to?
their relationship with the axillary artery
what are the cords of the brachial plexus?
medial
lateral
posterior
what makes the medial cord of the brachial plexus?
direct continuation of the anterior division of the inferior trunk
what makes the lateral cord of the brachial plexus?
the anterior divisions of the superior and middle trunks
what makes the posterior cord of the brachial plexus?
the posterior divisions of all three trunks
what do the cords of the brachial plexus come together to form?
the named nerves of the brachial plexus
what are the named nerves of the brachial plexus?
ulnar nerve musculocutaneous nerve axillary nerve radial nerve median nerve
what forms the median nerve?
continuation of the lateral cord
what forms the musculocutaneous nerve?
direct continuation of the lateral cord
what forms the axillary and radial nerves?
division of the posterior cord
what forms the median nerve?
the medial and lateral cords
where do the roots and trunks of the brachial plexus lie?
between the anterior and middle scalene muscles in the root of the neck
where do the divisions of the brachial plexus lie?
immediately posterior to the subclavian vessels in the root of the neck
where do the cords of the brachial plexus lie?
around the axillary artery (distal to the first rib)
what nerve wraps around the posterior aspect of the surgical neck of humerus?
axillary nerve
what nerve wraps around the posterior aspect of the mid shaft of the humerus?
radial nerve
what is the most medial named nerve in the brachial plexus?
ulnar nerve
what is the flexor retinaculum?
distal thickening of the antebrachial fascia
what is the proximal thickening of the antebrachial fascia called?
palmar carpal ligament
where does the flexor retinaculum attach?
lateral = scaphoid/trapezoid medial = pisiform/hamate
what forms the carpal tunnel?
carpal bones
flexor retinaculum
what does the carpal tunnel contain?
long tendons of FDS, FDP and FPL
median nerve
what causes carpal tunnel syndrome?
compression of the median nerve due to swelling in the carpal tunnel
what are the two branches of the radial artery?
superficial
deep
what are the four neurovascular bundles that supply each finger?
medial palmar
lateral palmar
medial dorsal
lateral dorsal
which tendons attach to the middle phalanges?
FDS
which tendons attach to the distal phalanges?
FDP
FPL
what is tenderness in the floor of the anatomical snuff box suggestive of?
scaphoid fracture
how many lumbricals are there?
four - one for each finger
where do lumbricals attach?
between the FDP tendon and the extensor expansion of the same digit
what is the action of the lumbricals?
flex the MCPJ
extend PIPJ
what nerve supplies the lumbricals?
medial two = ulnar nerve
lateral two = median nerve
what is the action of the palmar interossei?
adduct the digits
what is the action of the dorsal interossei?
abduct the digits
what nerve supplies the interossei?
ulnar
what are the three parts of the deltoid?
posterior (spinal)
middle (acromial)
anterior (clavicular)
what movement does the posterior deltoid allow?
extension at the shoulder
what movement does the middle deltoid allow?
abduction at the shoulder
takes over from supraspinatus beyond 15 degrees
what movement does the anterior deltoid allow?
flexion at the shoulder
what are the three parts of the trapezius?
ascending
middle
descending
what movements does levator scapulae enable?
elevation of the scapula
inferior rotation of the glenoid
what are the two rhomboids?
rhomboid major
rhomboid minor
what are the four rotator cuff muscles?
supraspinatus
infraspinatus
teres minor
subscapularis
what is the common thing all rotator cuff muscles do?
stabilise the head of the humerus in the glenoid
what movement does supraspinatus do?
first 15 degrees of shoulder abduction
what movement does infrapsinatus do?
lateral rotation of the shoulder
what movement does teres minor do?
lateral rotation at the shoulder
what movement does subscapularis do?
medial rotation at the shoulder
where do most rotator cuff muscles insert and which is the exception?
greater tubercle of the humerus
subscapularis
where does subscapularis insert?
lesser tubercle of the humerus
what makes up the nerve supply to the rotator cuff muscles?
branches of the brachial plexus
what nerve supplies the deltoid muscle?
axillary nerve
where does the deltoid attach proximally?
lateral third of the clavicle, inferior aspects of the scapular spine and acromion
where does the deltoid attach distally?
deltoid tuberosity of the humerus
where is the subacromial bursa located?
between the supraspinatus tendon and the acromion process of the scapula
what muscles make up the posterior compartment of the arm?
triceps brachii
what nerve innervates the triceps brachii?
radial nerve
this is the nerve to the posterior compartment of the arm
what are the three parts of the triceps brachii?
long head
lateral head
medial head
where does the long head triceps brachii attach proximally?
infraglenoid tubercle of the scapula
where does the lateral head triceps brachii attach proximally?
superior to the radial groove of the humerus
where does the medial head of triceps brachii attach proximally?
inferior to the radial groove of the humerus
where does the triceps brachii attach distally?
triceps tendon attaches to the olecranon process of the ulna
what movements are facilitated by triceps brachii?
weak extension at the shoulder joint
extension at the elbow joint
what nerve roots make up the axillary nerve?
C5-C6
what muscles are supplied by the axillary nerve?
deltoid
teres minor
what area of skin is innervated by axillary nerve?
the badge patch on the lateral aspect of the arm
what type of shoulder injury can cause damage to the axillary nerve?
inferior shoulder dislocation
how can the function of the axillary nerve be tested?
ask the patient to abduct the upper limb beyond 15 degrees
what nerve roots make up the radial nerve?
C5 - T1
where is the radial nerve found?
posterior compartment of the arm, in the radial groove of the humerus
then enters the posterior compartment of the forearm
what injury can cause damage to the radial nerve?
mid shaft fracture of the humeus
what are the branches of the radial nerve and where do these arise?
superficial and deep
divides just anterior to the lateral epicondyle
what is the deep branch of the radial nerve called when it enters the posterior compartment of the forearm?
the posterior interosseous nerve
