Upper arm LAB 3 Flashcards
clavicle
- only bone link between the upper limb and axial skeleton
- S-shaped
- medial third is convex anteriorly
- lateral third is concave anteriorly
- expanded medial end articulates with manubrium at the sternoclavicular joint
- flattened lateral end articulates with acromion of the scapula at the synovial acromioclavicular joint
sternoclavicular joint
clavicle and manubrium (sternum)
-mobile
acromioclavicular joint
- clavicle and acromion of the scapula
- synovial
- shoulder separation
scapula
- triangle
- covers the second to seventh ribs on the dorsum of the thorax
- medial border parallels the vertebral column
- long axillary border is thickened
- glenoid cavity- forms the joint surface for the humerus
- spine rises from the dorsal surface and projects laterally as the acromion
- spine separates the supraspinous fossa above from the infraspinous fossa
- coracoid process- fingerlike, projects anterolaterally from the superior border
- gently concave anterior surface of scapular blade comprises the subscapular fossa
- glenoid fossa articulates with humerus (laterally)
scapula: acromion
- bends anteriorly to overhand the glenoid cavity
- spine rises from the dorsal surface and projects laterally as the acromion
glenoid cavity
forms the joint surface for the humerus
-most mobility in the whole body
interclavicular ligaments
- reinforces the sternoclavicular joint
- runs between the medial ends of both clavicles and the top of the manubrium
costoclavicular ligament
- reinforces the sternoclavicular joint
- runs from the underside of the clavicle to the top of the first rib
coracoclavicular ligament
- reinforces the acromioclavicular joint
- extends from the coracoid process to the lateral third of the clavicle
coracoacromial ligament
- reinforces the acromioclavicular joint
- runs from the coracoid process to the acromioclavicular joint
humerus
- proximal end is the hemispherical head -> articulares with the glenoid fossa of the scapula
- greater tubercle- large, lateral to head
- lesser tubercle- smaller anterior to greater tubercle
- intertubercular sulcus- deep groove that runs longitudinally on the anterior surface between the greater and lesser tubercles
- deltoid tuberosity- midshaft below the greater tubercle, prominent
- medial epicondyle- distal end that expands medially (can be palpated)
- lateral epicondyle- smaller (on other side)
- distal end has 2 articular surfaces
- trochlea- medial, spool shaped, articulates with ulna
- capitulum- lateral, bulbous, articulates with the radius
- coronoid fossa- anterior, depression above the trochlea, receives the coronoid process of the ulna when the forearm is flexed
- radial fossa- lateral depression, above the capitulum, smaller, shallower, receive the head of the radius when the forearm is fully flexed
- olecranon fossa- posterior, large triangular depression proximal to the trochlea, receives the olecranon of the ulna when the forearm is fully extended
radius
- head- proximal end, articulates with ulna (medially) and the capitulum of the humerus (proximally)
- radial (bicipital) tuberosity- distal to head on anteromedial side, prominent
- distal end of radius is enlarged
- styloid process- lateral, projects distally, easily palpated
- lister’s dorsal tubercle- on dorsal aspect, palpable
- concave distal ends of radius articulates with two wrist bones (lunate and scaphoid)
ulna
- proximal end is expanded
- articulates with both radius and humerus
- olecranon- posterior, easily palpated, fits into the olecranon fossa of the humerus when forearm is extended
- trochlear notch- anterior aspect of proximal end, articulates with the trochlea of the humerus, extended anteriorly by the prominent coronoid process
- coronoid process- fits into the coronoid fossa of the humerus when the forearm is fully flexed
- radial notch- lateral to the coronoid process, shallow, articulates with head of radius
- head- distal end, articulates medially and anteriorly with the radius and distally with a fibrocartilage disc interposed between it an one of the carpal bones (triquetrum)
- styloid process- posterior to the head, short, fingerlike, projects distally
- interosseous membrane- connects the medial aspect of the radial shaft and the lateral aspect of the ulnar shaft, fibrous, serves as the attachment for some of thr muscles that move the thumb
carpals
- 8
- form wrist
- aligned in 2 transverse rows of 4
- proximal row- scaphoid, lunate, triquetrum, pisiform
- distal row- trapezium, trapezoid, capitate, hamate
sesamoid bone
- forms in the tendon of a muscle
- ex. pisiform
proximal row of carpals
- scaphoid, lunate, triquetrum, pisiform (lateral to medial)
- first 3- movement of wrist through their articulation with the radius and ulna
- pisiform- set anterior to the others and sits on the triquetrum, sesamoid bone that forms in the tendon of a flexor carpi ulnaris muscle
distal row of carpals
- trapezium, trapezoid, capitate, hamate (lateral to medial)
- participate in movement of the wrist through their articulation with the metacarpal bones of the palm
metacarpals
- 5
- form the palm
- first element of each ray is its metacarpal
- proximal end is expanded to form a base that articulate with one or more of carpal bone
- distal end has a rounded head that articulates with the proximal phalanx
- each metacarpal is slightly concave on palmar side and gently convex on dorsal side
phalanges
- 14
- digits
- each of the 4 fingers have: proximal phalanx, middle phalanx, distal phalanx
- thumb (pollex)- only has a proximal phalanx and distal phalanx
- distal end of each distal phalanx is expanded to form apical tuft (ungual tuberosity)- smooth on its dorsal (nail) side and rough on volar (pad) side
- apical tuft- provides support that enables the broad, fleshy fingertips to grip opposition with the thumb
shoulder joint
- articular cage covers head of humerus
- glenoid articular cartilage expanded around the rim to form a labrum
- the joint capsule attaches proximally to the rim of the glenoid and distally to the neck of the humerus
- lined with synovial membrane
- fibrous outer part is reinforced by glenohumeral ligaments
- joint capsule is pierced by tendon of the long head of biceps brachii- attaches to the top of the glenoid rim and runs through the capsule over the head of the humerus -> exits the capusle into the intertubercular sulcus on anterior aspect of humerus
- synovial membrane wraps around tendon sheath -> permits tendon free movement under the transverse humeral ligament between the greater and lesser tubercles of the humerus
glenohumeral ligaments
- thin and weak
- reinforced the fibrous outer part of joint capsule in shoulder
rotator cuff muscles
- shoulder joint is reinforced by tendons of 4 muscles
- all the posterior insert on greater tubercle -> laterally rotate
- anterior insert on lesser tubercle
- supraspinatus- passes the joint superiorly, posteriorly
- subscapularis- passes joint anteriorly
- infraspinatus- pass joint posteriorly
- teres minor- pass joint posteriorly
- form an incomplete cuff around shoulder joint
- prevent shoulder dislocation
shoulder bursae
- subacromial bursa- superior, lies beneath the acromion of the scapula and above the tendon of the supraspinatus
- subscapular bursa- anterior, located between the tendon of the subscapularis muscle and the joint capsule, an extension of the synovial membrane of the joint capsule
3 articulations of elbow joint
- hinge joint between humerus and ulna
- ball and socket joint between humerus and radius
- pivot joint between radius and ulna
- contained within the joint capsule and synovial cavity
- 1 & 2 -> permits ulna and radius to flex and extend
- 2 &3 -> permit medial and lateral rotation (pronation and supination) of radius
elbow joint
- articular cartilage covers the trochlea of humerus and the opposing trochlear notch of the ulna
- also covers the capitulum of humerus and opposing head of radius
- also covers radial notch of ulna and the opposing head of radius
- fibrous joint capsule is lined with synovial membrane
ligaments of elbow joint
- 3 extracapsular ligaments reinforce
- annular ligament
- radius and ulna are held against the humerus by ligaments on the medial and lateral sides of the joint
annular ligament
- elbow joint
- holds the head of radius tightly against the ulna
- sweeps around the circumference of the radial head from margin of ulnar radial notch to the other
ulnar collateral ligament
- elbow joint
- arises from the medial epicondyle of the humerus and fans out to attach to the medial side of the ulna
- prevents from abduction and adduction elbow
radial collateral ligament
- elbow joint
- arises from the lateral epicondyle of the humerus and fans out to insert into the annular ligament and the lateral aspect of the ulna
- prevents from abduction and adduction elbow
bursae of elbow
- posterior to joint
- subtendinous olecranon bursa- lies between the joint and the tendon of the triceps brachii muscle which inserts onto the apex of the olecranon of the ulna
- subcutaneous olecranon bursa- lies immediately below the skin at the back of the ulnar olecranon
2 articulations of wrist joint
- between the distal ends of the radius and ulna
- between the forearm bones and the proximal row of carpals
- 1 is the distal radioulnar joint
- 2 is radiocarpal joint
distal radiolulnar joint
- permits pronation and supination of the forearm and hand
- concave ulnar botch and the radius sweeps around the head of the ulna
- between the distal ends of the radius and ulna
triangular disc of wrist joint
- stabilizes the joint
- fibrocartilage that covers the distal end of the ulna
- extends from the edge of the ulnar notch of the radius to the styloid process of the ulna
- interposed between the ulna and carpal bones (lunate and triquetral)
- glides across the ulnar head and the radius moves around it
radiocarpal joint
- permits flexion and extension as well as abduction and adduction of the hand
- formed by the distal end of the radius and the triangular disc, which articulate, respectively with the scaphoid, lunate, and triquetrum distally
- between the forearm bones and the proximal row of carpals
- radius articulates with scaphoid and lunate
- triangular disc articulates with lunate during abduction and pure flexion and extension
- when hand is adducted triangular disc articulate with triquetrum
radiocarpal ligaments
- provides stability for wrist joint
- dorsally and ventrally
ulnocarpal ligaments
- provides stability for wrist joint
- dorsally and ventrally
radial collateral ligament
- provides stability for wrist joint
- between the styloid process of the radius and the scaphoid
ulnar collateral ligament
- provides stability for wrist joint
- between the styloid process of the ulna and the triquetral
flexor retinaculum
- strong transverse ligament that extends from the pisiform and hamate medially to the scaphoid and trapezium laterally
- *creates a carpal tunnel that prevents the flexor tendons from bowstringing when the muscles contract
carpal tunnel
- transmit 9 tendons from the muscles that flex the fingers and thumb
- tendon of the flexor carpi radialis muscle runs underneath the flexor retinaculum but does not pass through the carpal tunnel proper
muscles of the upper limb
- two compartments: dorsal and ventral
- each is surrounded by a layer of deep fascia with muscles, nerves, and blood vessels
- they are supplied by the ventral rami of spinal nerves
brachial plexus
- in order to provide muscles with nerve fibers from more than one spinal nerve the ventral rami are braided together -> brachial plexus
- supply the muscles of upper limbs
shoulder: dorsal muscle
- includes muscles that cross the shoulder joint and originate in vertebral column, the back of rib cage, and scapula
- stabilize the shoulder joint
- extend and adduct arm
arm: dorsal muscle
-extends forearm
forearm: dorsal muscle
-supinate the forearm, extend the wrist and extend and abduct the fingers and thumb
hand: dorsal muscle
-intrinsic hand muscles that move the thumb and fingers are all ventral
shoulder: ventral muscles
- muscles that cross the shoulder joint and originate from the front of the rib cage, clavicle, and coracoid process of scapula
- flex the arm
arm: ventral muscles
-flex and supinate forearm
forearm: ventral muscles
- flex, abudct, and adduct the wrist
- flex the fingers and thumb
hand: ventral muscles
- intrinsic hand muscles
- abduct and adduct, flex and extend the fingers and thumb
- all are ventral
roots
-5 ventral rami comprise the 5 roots of the plexus
trunks
- roots combine to form 3 trunks:
- superior
- middle
- inferior
- each trunk has axons that will go to dorsal and ventral compartment muscles
cords
- from each trunk the axons that supply a dorsal compartment split apart from the ones that supply a ventral compartment
- split forms 3 cords:
- lateral
- medial
- posterior
- named with according position to brachial artery
- axons of each cord travel only to dorsal compartment muscles or only to ventral compartment muscles
- lateral and medial cords carry ventral compartment axons
- posterior cord carries dorsal compartment axons
peripheral nerves
- axons of each cord separate and form peripheral nerves that innervate muscles
- lateral pectoral nerve
- musculocutaneous nerve
- median nerve
- medial pectoral nerve
- ulnar nerve
- axillary nerve
- radial nerve
- subscapular nerve
lateral cord
- carry ventral compartment axons
- yields the lateral pectoral nerve, musculocutaneous nerve, and part of median nerve
medial cord
- carry ventral compartment axons
- yields the medial pectoral nerve, the ulnar nerve, and the other part of median nerve
superior trunk
- yields the suprascapular nerve
- the only nerve to emerge directly from a trunk
- innervates dorsal compartment muscles
posterior cord
- yields the subscapular nerve, the radial nerve, and the axillary nerve
- carries dorsal compartment axons
scapulohumeral muscles
- muscles that move the arm (insert on humerus)
- origin from the scapula
- 7
- 4 from rotator cuff
- 6 innervated by dorsal compartment nerves
- coracobrachialis
- teres major
- deltoid
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
thoracohumeral muscles
- muscles that move the arm (insert on humerus)
- arise from the thoracic axial skeleton (vertebral column and ribs)
- ventral compartment = medial and lateral pectoral nerves
- 2
- latissimus dorsi
- pectoralis major
coracobrachialis
- scapulohumeral muscles
- ventral compartment
- musculocutaneous nerve
teres major
- scapulohumeral muscle
- dorsal compartment
- lower subscapular nerve
deltoid
- scapulohumeral muscle
- dorsal compartment
- originates on spine of scapula, acromion, and lateral clavicle
- inserts on deltoid tuberosity of humerus
- crosses shoulder joint from 3 diff sides -> 3 diff actions
- flexes (anterior), abducts (lateral), and extends (posterior) the arm
- innervated by axillary nerve
supraspinatus
- scapulohumeral muscle
- dorsal compartment
- suprascapular nerve
infraspinatus
- scapulohumeral muscle
- dorsal compartment
- suprascapular nerve
teres minor
- scapulohumeral muscle
- dorsal compartment
- axillary nerve
subscapularis
- scapulohumeral muscle
- dorsal compartment
- upper and lower subscapular nerves
latissimus dorsi
- thoracohumeral muscle
- dorsal compartment
- thoracodorsal nerve
pectoralis major
- thoracohumeral muscle
- ventral compartment
- medial and lateral pectoral nerves
- adducts and medially rotates humerus
- comes from sternum and clavicle
- anteriorly crosses shoulder joint
- inserts on anterior humerus
- innervated my brachial plexus (medial and lateral pectoral nerves)
ventral compartment muscles of the arm
- fleshy belly lies in the ventral compartment of the arm will be supplied by the musculocutaneous nerve
- bicep brachii
- brachialis
- coracobrachialis
- musculocutaneous nerve
- flexion
- brachial artery
bicep brachii
- supplied by the musculocutaneous nerve
- ventral compartment
- musculocutaneous nerve
- arm
brachialis
- supplied by musculocutaneous nerve
- ventral compartment
- musculocutaneous nerve
- arm
dorsal compartment muscle of the arm
- fleshy belly lies in the dorsal compartment of arm
- supplied by the radial nerve
- triceps brachii
triceps brachii
- supplied by radial nerve
- dorsal compartment
- radial nerve
- arm
- 3 heads-> long, lateral, medial
- insert of olecranon process of ulna
ventral compartment muscles of the forearm
- fleshy belly lies in ventral compartment of forearm
- supplied by median nerve or ulnar nerve
- pronator teres
- pronator quadratus
pronator teres
- ventral compartment
- median nerve
- move forearm
pronator quadratus
- ventral compartment
- median nerve
- move forearm
dorsal compartment muscles of the forearm: wrist, fingers, and thumb
-fleshy belly lies in dorsal compartment of the forearm
-supplied by the median nerve or ulnar nerve
wrist:
-felxor carpi radialis
-flexor carpi ulnaris
-palmaris longus
fingers and thumb:
-flexor digitorum superficialis
-flexor digitorum profundus
-flexor pollicis longus
flexor carpi radialis
- ventral compartment
- median nerve
- move wrist
flexor carpi ulnaris
- ventral compartment
- ulnar nerve
- move wrist
palmaris longus
- ventral compartment
- median nerve
- move wrist
flexor digitorum superficialis
- ventral compartment
- median nerve
- moves fingers and thumb
flexor digitorum profundus
- ventral compartment
- median and ulnar nerve
- moves fingers and thumb
flexor pollicis longus
- ventral compartment
- median nerve
- moves fingers and thumb
dorsal compartment muscles of the forearm: move forearm
- felly belly lies in dorsal compartment of forearm
- supplied by radial nerve
- brachioradialis
- supinator
brachioradialis
- dorsal compartment
- radial nerve
- move forearm
supinator
- dorsal compartment
- radial nerve
- move forearm
dorsal compartment muscles of the forearm: wrist, fingers and thumb
-fleshy belly lies in the dorsal compartment of the forearm
-supplied by the radial nerve
wrist:
-extensor carpi radialis longus
-extensor carpi radialis brevis
-extensor carpi ulnaris
fingers:
-extensor digitorum
-extensor digiti minimi
-extensor indicis
thumb:
-extensor pollicis longus
-extensor pollicis brevis
-abductor pollicis longus
extensor carpi radialis longus
- dorsal compartment
- radial nerve
- move wrist
extensor carpi radialis brevis
- dorsal compartment
- radial nerve
- move wrist
extensor carpi ulnaris
- dorsal compartment
- radial nerve
- move wrist
extensor digitorum
- dorsal compartment
- radial nerve
- move fingers
extensor digiti minimi
- dorsal compartment
- radial nerve
- move fingers
extensor indicis
- dorsal compartment
- radial nerve
- move fingers
extensor pollicis longus
- dorsal compartment
- radial nerve
- move thumb
extensor pollicis brevis
- dorsal compartment
- radial nerve
- move thumb
abductor pollicis longus
- dorsal compartment
- radial nerve
- move thumb
ventral compartment muscles of the hands
- fleshy belly lies in the ventral compartment of the hand
- supplied by either median nerve or ulnar nerve
- 5
- only ventral
- flexor digiti minimi
- abductor digiti minimi
- opponens digiti minimi
- lumbrical muscles
- interossei muscles
flexor digiti minimi
- ventral compartment
- ulnar nerve
- move hand
abductor digiti minimi
- ventral compartment
- ulnar nerve
- move hand
opponens digiti minimi
- ventral compartment
- ulnar nerve
- move hand
lumbrical muscles
- ventral compartment
- ulnar and median nerve
- move hand
interossei muscles
- ventral compartment
- ulnar nerve
- move hand
ventral compartment nerves
- musculocutaneous
- median
- ulnar
musculocutaneous nerve
- ventral compartment
- arises about an inch below the coracoid process of scapula
- pierces the coracobrachialis muscle
- crosses the anterior compartment of the arm
- supplies 3 muscles of that compartment and the elbow joint
median nerve
- ventral compartment
- descends with the brachial artery along the medial aspect of the arm
- follows a median course along the forearm
- crosses wrist at carpel tunnel
ulnar nerve
- ventral compartment
- arises about an inch below coracoid process of scapula
- runs with median nerve and brachial artery to about the middle of the arm
- turns posteriorly and passes behind the medial epicondyle of the humerus
- run in contact with the capsule of the elbow joint
- funny bone nerve
- continues distally by turning anteriorly to run along the ulna
- crosses the wrist anterior to the carpal tunnel
dorsal compartment nerves
- suprascapular
- axillary
- radial
suprascapular nerve
- dorsal compartment
- curves over onto the dorsal surface of the scapula through the notch in the upper border of that bone adjacent to coracoid process
axillary nerve
- dorsal compartment
- runs across anterior surface of subscapularis muscle
- exits the axilla between it and the teres major muscle
- runs behind humerus
radial nerve
- dorsal compartment
- largest branch of the brachial plexus
- descends along back of humerus
- curves around to emerge at elbow anterior to lateral epicondyle of humerus
- divides into two branhces
- one supplies muscles of posterior compartment of forearm
- other continues distally along the lateral side of the radius to supply skin of the back of the hand
ventral compartment muscles
- innervated by ventral division nerves:
- lateral pectoral
- medial pectoral
- musculocutaneous
- median
- ulnar
dorsal compartment muscles
- innervated by dorsal division nerves:
- suprascapular
- subscapular
- axillary
- radial
thoracohumeral muscles
- 2
- latissimus dorsi
- pectoralis major
pectoralis major
- large muscle on front of chest
- arises from the medial half of the clavicle, sternum, and part of 7th rib
- inserts onto greater tubercle of humerus
- adducts and medially rotates the humerus
- clavicular part also flexes the shoulder joint whereas the sternal part extends an already flexed arm
- ventral compartment = medial and lateral pectoral nerves
coracobrachialis
- runs from the tip of the coracoid process of the scapula to the medial side of the middle of the humeral shaft
- adducts and flexes the arm
- ventral compartment = musculocutaneous nerve
teres major
- runs from the dorsal surface of the scapular blade to the lesser tubercle of the humerus
- adducts, medially rotates, and extends arm
- dorsal compartment = lower suprascapular arm
rotator cuff muscles
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
supraspinatus
- runs from the supraspinous fossa of the scapula across the top of the shoulder joint to insert onto the greater tubercle of the humerus
- elevates and abducts the arm
- dorsal compartment = suprascapular nerve
infraspinatus
- runs from the infraspinous fossa of the scapula across the back of the shoulder joint to the greater tubercle of the humerus
- laterally rotates the arm
- dorsal compartment = suprascapular nerve
teres minor
- arises from the drosal surface of the scapula along its axillary border just superior to the origin of teres major
- runs across the back of the shoulder joint to the greater tubercle of the humerus
- laterally rotates the arm but only when its adducted
- dorsal compartment = axillary nerve
subscapularis
- arises from the anterior surface of the blade of the scapula (subscapular fossa)
- runs across the front of the shoulder joint
- inserts onto the lesser tubercle of the humerus
- medially rotates the arm
- dorsal compartment = upper and lower subscapular nerves
elbow flexors
- biceps brachii
- brachialis
- brachioradialis
bicep brachii
- arises by 2 separate scapular attachments that merge to forma single belly
- long head- arises from a tubercle above the glenoid fossa -> its tendon passes through the shoulder joint capsule and runs along the intertubercular groove of the humerus
- short head- arises from the coracoid process
- unified belly inserts onto the tuberosity of the radius
- some tendinous fibers separate from it above the elbow and sweep medially to form the bicipital aponeurosis -> merges with the deep fascia
- flexes the elbow
- supinator
- ventral compartment = musculocutaneous nerve
brachialis
- arises from the front of the humeral shaft and inserts onto the ulna at the base of the coronoid process
- flexes the elbow when forearm is pronated or supinated
- ventral compartment = musculocutaneous nerve
brachioradialis
- originates on the lateral edge of the humerus above the lateral epicondyle
- inserts onto the radius close to the styloid process
- flexes elbow
- dorsal compartment = radial nerve
elbow extensors
- triceps brachii
- anconeus
triceps brachii
- 3 bellies that merge to insert onto the olecranon of the ulna
- long head- arises from the inferior rim of the glenoid fossa of the scapula
- lateral head- arises from the humerus between the greater tubercle and deltoid tuberosity
- medial head- arises from the posterior surface of the humerus
- long head extends forearm and adducts and extends the humerus
- dorsal compartment = radial nerve
anconeus
- runs from the back of the lateral epicondyle of the humerus to the lateral side of the olecranon of the ulna
- extends the forearm
- dorsal compartment = radial nerve
pronators of the forearm
- pronator teres
- pronator quadratus
- ventral compartment = median nerve
pronator teres
- arises from the medial epicondyle of the humerus and crosses the elbow
- insert onto the lateral side of the radius shaft
- addition to being pronator -> also a weak flexor of elbow
- ventral compartment = median nerve
pronator quadratus
- located just above wrist
- runs from the anteromedial edge of the ulna to the anterior surface of the radius
- ventral compartment = median nerve
deltoid
- attaches to the spine and acromion of the scapula and to the lateral third of the clavicle
- inserts onto the deltoid tuberosity of the humerus
- felxes, abducts, and extends the arm
- dorsal compartment = axillary nerve
supinators of the forearm
- supinator
- biceps brachii
supinator
- arranged in 2 layers
- superficial layer arises from the lateral epicondyle of the humerus -> runs behind the radial head and turns forward -> inserts onto the front of the radial shaft
- deep layer arises from the lateral side of the upper end of the ulna -> runs behind the radius and turns forward -> insert on the front of the upper part of the radial shaft
- dorsal compartment = radial nerve
biceps brachii
- powerful flexor of elbow and shoulder
- important supinator of forearm
- does not flex when pronated
- ventral compartment = musculocutaneous nerve
flexors of the wrist
- arise from the medial epicondyle of the humerus by a common tendon
- all are ventral compartment
- flexor carpi radialis
- flexor carpi ulnaris
- palmaris longus
flexor carpi radialis
- crosses the radial side of the forearm to attach to the bases of the 2nd and 3rd metacarpals
- abducts the wrist
- ventral compartment = median nerve
flexor carpi ulnaris
- runs along the ulnar side of the forearm to attach to the pisiform and then onto the base of the 5th metacarpal
- adducts the wrist
- ventral compartment = ulnar nerve
palmaris longus
- runs between the other 2 flexors at attach to the front of the flexor retinaculum
- fans out to form 4 separate bands that join the flexor sheaths of the fingers
- bands are connected by fibrous tissue that forms a sheet known as the palmar aponeurosis
- ventral compartment = median nerve
extensors of the wrist
- arise from the lateral epicondyle of the humerus
- all are dorsal
- extensor carpi radialis longus
- extensor carpi radialis brevis
- extensor carpi ulnaris
extensor carpi radialis longus
- runs along the lateral side of the forearm
- insert onto the base of the 2nd metacarpal
- also abducts the wrist
- dorsal compartment = radial nerve
extensor carpi radialis brevis
- runs along the lateral side of the forearm
- insert onto the base of the 3rd metacarpal
- abducts the wrist
- dorsal compartment = radial nerve
extensor carpi ulnaris
- arises from the back of the ulnar shaft
- conjoined fibers runs along the medial side of the forearm
- insert onto the base of the 5th metacarpal
- adducts the wrist
- dorsal compartment = radial nerve
muscles that move the fingers
- 10
- 2 groups
- 5 extrinsic arise from arm or forearm
- 5 intrinsic originate from within the hand itself
-extrinsic flexors of the fingers
- tendons run through the carpal tunnel
- ventral compartment
- flexor digitorum superficialis
- flexor digitorum profundus
flexor digitorum superficialis
- arises from the medial epicondyle of the humerus and the medial side of the coronoid process of the ulna
- also arises from the shaft of the radius
- conjoined fibers run down the forearm deep to the wrist flexors
- above the wrist it gives rise to 4 tendons -> each insert onto middle phalanx after separating around the flexor digitorum profundus tendon over the proximal phalanx
- ventral compartment = median nerve
flexor digitorum profundus
- arises from the ulnar shaft
- also gives rise to 4 tendons, each of which insert onto a distal phalanx
- ventral compartment = median and ulnar nerve
extrinsic extensor of the fingers
- dorsal compartment muscles
- extensor digitorum
- extensor digiti minimi
- extensor indicis
extensor digitorum
arises from the lateral epicondyle of the humerus
- gives rise to 4 tendons, each of which inserts onto a distal phalanx
- dorsal compartment = radial nerve
extensor digiti minimi
- arises from the lateral epicondyle of the humerus and runs to the 5th digit
- dorsal compartment = radial nerve
extensor indicis
- a deep muscle that originates along the distal part of the ulnar shaft and runs to the 2nd digit
- dorsal compartment = radial nerve
intrinsic muscles of the fingers
- 3 out of 5 run from the flexor retinaculum to the little finger -> form the hypothenar eminence on the medial side of the palm
- all are ventral compartment
- flexor digit minimi
- abductor digiti minimi
- opponens digiti minimi
- lumbricals
- interossei
flexor digiti minimi
- arises form the flexor retinaculum
- inserts onto the base of the proximal phalanx of the 5th digit
- flexes the 5th digit
- ventral compartment = ulnar nerve
abductor digiti minimi
arises from the flexor retinaculum
- inserts onto the base of the proximal phalanx of the 5th digit
- abducts and flexes the 5th digit
- ulnar nerve
opponens digiti minimi
- arises from the flexor retinaculum
- inserts onto the 5th metacarpal
- flexes and laterally rotates the metacarpal to a slight degree
- causes the ventral surface of the little finger to face the thumb when the tips of these digits are opposed
- ulnar nerve
lumbricals
- 4- > one for each finger
- each arise from the tendon of flexor digitorum profundus
- runs along the lateral side of that of that tendon to insert onto the base of the proximal phalanx
- then turns dorsally to join the common extensor tendon
- flexes the metacarpophalangeal (MP) joint and extends the proximal interphalangeal (IP) joint
- median and ulnar nerves
interossei
- 7 interosseous muscles
- 3 palmar interossei adduct the fingers toward the midline
- 3rd digit cannot be adducted -> it has no palmar interosseus muscle
- runs from a metacarpal to the base of a proximal phalanx (occasionally a fourth interosseus muscle of thumb)
- the 4 dorsal interossei abduct the fingers away from the midline (third digit requires 2 muscles)
- each arises from the opposing surfaces of 2 adjacent metacarpals to insert onto the base of the proximal phalanx
- dorsal interossei are so named bc they lie dorsal to the palmar interossei, but they still occupy the ventral compartment of the hand
- ulnar nerve
muscles that move the thumb
- 8
- 2 groups of 4
- extrinsic that originate from the forearm
- intrinsic that originate from within the hand itself
- flexor pollicis longus
- abductor pollicis longus
- extensor pollicis longus
- extensor pollicis brevis
flexor pollicis longus
arises from the anterior surface of the radial shaft
- interosseous membrane and the medial side of the coronoid process of the ulna
- its long tendon runs through the carpal tunnel to insert onto the ventral surface of the base of the distal phalanx
- only extrinsic thumb muscle in the anterior compartment of the forearm
- ventral compartment = median nerve
abductor pollicis longus
- arises from the posterior surfaces of the radius, ulna, and interosseous membrane
- tendon runs past the styloid process of the radius to insert onto the lateral side of the base of the 1st metacarpal
- its tendon forms part of the anterior margin of the anatomical snuff box
- also lateral rotates the thumb
- dorsal compartment = radial nerve
extensor pollicis longus
- arises from the back of the ulnar shaft and inserts onto the dorsal surface of the distal phalanx
- its tendon forms the posterior margin of the anatomical snuff box
- dorsal compartment = radial nerve
extensor pollicis brevis
- arises from the posterior surface of the radius and interosseous membrane and inserts on the dorsal surface of the base of the proximal phalanx
- its tendon forms part of the anterior margin of the anatomical snuff box
- dorsal compartment = radial nerve
intrinsic muscles of the thumb
- 4
- ventral
- 3 arise from the flexor retinaculum and form the thenar eminence on the lateral side of the palm
- they act together to produce opposition of the thumb
- 4th muscle -> adductor pollicis -> lies deep in the palm
flexor pollicis brevis
- arises from the flexor retinaculum and the trapezium
- inserts onto the lateral aspect of the base of the proximal phalanx
- opposes and flexes the thumb
- median and ulnar nerves
abductor pollicis brevis
- arises form the flexor retinaculum as well as the scaphoid and trapezium
- inserts with the tendon of flexor pollicis brevis onto the lateral side of the base of the proximal phalanx
- opposes and abducts the thumb
- median nerve
opponens pollicis
- arises from the flexor retinaculum and trapezium
- insert onto the lateral surface of the 1st metacarpal
- produces opposition
- median nerve
adductor pollicis
- arises from the capitate, and from the shaft of the 3rd metacarpal
- the fibers converge to insert onto the medial side of the base of the proximal phalanc
- flexes the thumb when it is an adducted position
- ulnar nerve
aortic arch
-give blood to upper limb on both sides of the body just above the heart
brachiocephalic trunk
- blood travels from the aortic arch into the brachiocephalic trunk to get to the right upper limb
- trunk divides into the right common carotid artery and the right subclavian artery
subclavian artery
- blood travels from the aortic arch directly into its 3rd principal branch -> the left subclavian artery
- to get to the left upper limb
- arises from the aortic arch immediately after the origin of the left common carotid artery
- on both sides of the body the subclavian artery runs laterally between the clavicle and first rib
- past the rib the subclavian artery becomes the axillary artery
axillary artery
- past the edge of the rib the subclavian artery becomes the axillary artery
- runs through the axilla
- past the lower edge of the teres major muscle it takes on another name -> brachial artery
brachial artery
- past the lower edge of the teres major muscle the axillary artery becomes the brachial artery
- runs along the medial side of the arm
- above the elbow the brachial artery emerges from underneath the bicep brachii muscle onto the front of the brachialis muscle -> pulse felt here
- continues distally into cubital fossa -> divides into two branches just below the elbow
radial artery
- one branch of the brachial artery
- runs along the tendon of the brachioradialis muscle to cross the distal end of the radius
- pulse is most easily felt here
- crosses the wrist through the anatomical snuff box and then divides into 2 main branches -> deep palmar arch and ulnar artery
deep palmar arch
- a branch of the radial artery
- supplies the deep hand muscles
ulnar artery
- branch of the radial artery
- turns posteriorly to supply the back of the hand
- runs medially and deeply underneath the pronator teres muscle and between the flexor carpi ulnaris and flexor digitorum profundus muscles
- runs with the ulnar nerve across the flexor retinaculum of the wrist and in the hand becomes the superficial palmar arch
superficial palmar arch
- branched from the ulnar artery
- supplies the superficial hand muscles
deep veins: upper arm
- run alongside the arteries
- venae comitantes
- named according to artery they accompany
- continuous with superficial veins that feed them
- basilic vein is joined on the medial side of the arm by the venae comitantes of the axillary artery to become the axillary vein
- axillary vein is joined by the cephalic vein to become the subclavian vein
- subclavian veins on both sides of body are symmetrical in terms of their structure -> join the roots of the external and internal jugular veins to form the brachiocephalic vein
- left and right brachiocephalic veins join to form the superior vena cava which drains directly into the heart
superficial veins
- run in the superficial fascia and subcutaneous tissue
- cephalic vein
- basilic vein
- median cubital vein
- median antebrachial vein
- drain into deep veins
cephalic vein
- drains the back of the hand
- arises on the posterolateral side of the wrist -> turns to run up the anterior and lateral aspect of the forearm
- crosses the elbow in front of the lateral epicondyle on the humerus and runs upward along the lateral edge of the biceps brachii -> turns onto the front of the shoulder between the deltoid and pectoralis major muscles
- empties into the axillary vein
basilic vein
- major superficial vein on the medial side of the arm
- arises on the medial side of the wrist and runs upward along the flexor carpi ulnaris muscle -> crosses the elbow in front of the medial epicondyle of the humerus -> continues proximally between the biceps brachii and brachialis muscles
- joined by the median cubital vein in the cubital fossa on the anterior aspect of the elbow
- basilic bein in continuous with the axillary vein, which is joined by the cephalic vein to become the subclavian vein
median cubital vein
- large anastomotic channel between the cephalic and basilic veins
- leaves the cephalic vein just distal to the elbow -> crosses the cubital fossa
- joins the basilic vein just above the medial epicondyle of the humerus
- used to draw blood
median antebrachial vein
- drains the palm of the hand
- arises on the ventral surface of the wrist and runs straight up the forearm to empty into the median cubital vein
upper limb=
pectoral girdle + free part
pectoral girdle=
scapula + clavicle
supraglenoid tubercle
- origin of long head of biceps brachii
- bump above the glenoid fossa
infraglenoid tubercle
- origin site of the long head of tricep brachii
- below glenoid fossa
intertubercular sulcus
-tendon of the long head of bicep brachii will pass through here
deltoid tuberosity
-where the deltoid attaches
glenohumeral joint
- humeral head and glenoid fossa
- articulating surfaces covered in hyaline cartilage
- tendon of long head of bicep brachii pierces the joint capsule
- synovial
- most mobile joint
- some stability from rotator cuff muscles as well as from ligaments
- dislocation
sternoclavicular joint ligaments
- intercalvicular ligament
- costoclavicular ligament
- sternoclavicular ligament
acromioclavicular joint ligaments
- acromioclavicular ligament
- coracoclavicular ligament
- coracoacromial ligament
shoulder dislocation
-at the glenohumeral joint
shoulder separation
- happens at the acromioclavicular joint
- displacement of the clavicle
arm flexors
- anterior part of deltoid
- pectoralis major
- biceps brachii
- coracobrachialis
arm extensors
- posterior part of deltoid
- teres major
- latissimus dorsi
- long head of triceps brachii
- pectoralis major- sternocostal head, but only from a flexed position
short head and medial head
- do not cross the shoulder joint -> cannot extend the shoulder
- long head does -> extends
arm abductors
- run medio-laterally, superior to the glenohumeral joint
- middle part of deltoid
- inserts on humerus
- supraspinatus
- deltoid
arm adductors
- run medio-laterally inferior to the glenohumeral joint
- pectoralis major
- latissimus dorsi
- teres major
- coracobrachialis
- short head of biceps brachii
medial rotators of the arm
- medial rotators wrap around humerus
- latissimus dorsi
- teres major
- subscapularis pectoralis major
lateral rotators of the arm
- posteriorly
- lateral rotators also wrap around humerus
- teres minor
- infraspinatus
compartment
-group of muscles surrounded by a thickened layer of deep fascia
anterior compartment of the arm
- biceps brachii
- coracobrachialis
- brachialis
- musculocutaneous nerve
- flexion
- brachial artery
posterior compartment of the arm
- triceps brachii
- long head
- medial head
- lateral head
- anconeus
- radial nerve
- deep brachial artery
carpi=
wrist
digitorum=
fingers
profundus=
deep
superficialis=
superifical
brevis=
short
pollicis=
thumb
minimi=
pinky
opponens=
opposition
anterior compartment of forearm
- pronator teres
- plexor carpi radialis
- palmaris longus (middle finger)
- flexor carpi ulnaris (ring finger)
- middle layer- flexor digitorum superficialis
- attach to medial epicondyle of humerus
- flexors
deep layer of forearm
- flexor digitorum profundus
- flexor pollicis longus
- pronator quadratus
- flexors except pronator quadratus
posterior compartment of forearm
superficial layer -brachioradialis (exception- flexor) -extensor carpi radialis longus -extensor carpi radialis brevis -extensor digitorum -extensor digiti minimi -extensor carpi ulnaris deep layer -supinator -abductor pollicis longus -extensor pollicis brevis -extensor pollicis longus -extensor indicis -radial nerve
anatomical snuffbox
- Border- abductor pollicis longus and extensor pollicis brevis (lateral border-thumb) and extensor pollicis longus (medial border)
- contents- radial artery
muscles of the hand: ventral
Thenar eminence- thumb -flexor pollicis brevis -abductor pollicis brevis -opponens pollicis (deepest) Hypothenar eminence- pinky -flexor digiti minimi brevis -abductor digiti minimi -opponens digiti minimi Lumbricals -4 Interossei- 7- palmar and dorsal: PAD- palmar adduct DAB- dorsal abduct