4 UE Arm + Forearm Flashcards
axilla
(armpit) inferior to shoulder joint
- superior to axillary fascia @ juction of arm y thorax
apex boundary of axilla
middle 1/3 of clavicle (cervico-axillary canal)
base boundary of axilla
axillary fascia
anterior wall boundary of axilla
pectoralis muscles (major + minor)
posterior wall boundary of axilla
subscapularis
teres major
latissimus dorsie (anterior scapulae)
medial wall boundary of axilla
serratus anterior (ribs)
lateral wall boundary of axilla
biceps brachii
coracobrachialis (humerus)
cervico-axillary canal
passage between neck + axilla for VAN
contents of axilla
portions of biceps brachii + coracobrachialis muscles
- breast tissue (females)
nerves of the axilla
(1) cords + branches of brachial plexus
(2) pectoral nerve
(3) subscapular nerve
(4) long thoracic nerve
blood vessels of the axilla
axillary vein
axillary artery
axillary vein
drains axilla
- large
- exposed
axillary artery
supplies axilla
- palpable against lateral wall (medial wall of arm)
clinical application: AXILLA
ticklish = somatic reflexes to protect nerves
axillary lymph nodes
apical nodes receive lymphatic flow from other axillary nodes
clinical application: AXILLARY NODES
plays essential role in cancer spreading
- receive lymphatic flow from other axillary nodes
compartments of the arm
anterior compartment
posterior compartment
anterior compartment of the arm
3 flexors supplied by musculocutaneus nerve
front - flexors (M)
flexors of anterior compartment in the arm
(1) coracobrachialis
(2) biceps brachii
(3) brachialis
posterior compartment of the arm
1 extensor supplied by radial nerve
- triceps brachii
back = extend (R)
synergist
muscles that help the prime movers
antagonist
muscles that work against synergist + prime mover
coracobrachialis
anterior arm compartment
O: coracoid process of scapula
I: medial humerus
A: flex & stabilize arm + weak addution of arm
N: musculocutaneous (C6 – C7)
biceps brachii
anterior arm compartment
O: long head (lateral): supraglenoid tubercle of scapula + short head (medial): coracoid process of scapula
I: radial tuberosity + bicipital aponeurosis
A: 1˚ supinator & flexes forearm
N: musculocutaneous (C5 – C6)
brachialis
anterior arm compartment
O: anterior & distal ½ humerus
I: coronoid process + tuberosity of ulna
A: flex forearm (1˚ flexor)
N: musculocutaneous (C5 – C6)
triceps brachii
posterior arm compartment
O: (long head) infraglenoid tubercle of scapula + (lateral head) upper posterior humerus + (medial head) lower posterior humerus
I: olecranon
A: extend forearm + (long head) aids adduction if arm is abducted
N: radial nerve (C6 – C8)
*most commonly injured nerve since extremely peripheral
elbow articulations
humerus + ulna
humerus + radius
elbow arthrology
hinge synovial
- movement: flexion + extension
- carrying angle: 170˚
**most power at an angle in anatomical position rather than straight
carrying angle
angle where elbow sits in anatomical position
elbow ligaments (3)
ulnar collateral ligament
radial collateral ligament
anterior ligament of radius
clinical application: ELBOW
student’s elbow
ulnar collateral ligament reconstruction
student’s elbow
bursitis/inflammation of subcutaneous bursa (olecranon bursa)
- very superficial
- easier to agitate
ulnar collateral ligament (UCL) reconstruction
“Tommy John surgery”
- named after the 1st baseball player who had the surgery
- surgery to reconstruct ulnar collateral ligament
- common in athletes who throw
- caused by repetitive stress on elbow tendons
- use palmaris long use tendon for replacing ulnar collateral ligament
- long recovery
- causes tingling sensation of funny bone
palmaris longus tendon
tendon located on palmar side of wrist
- absent in 15-20% of population
- used for grafting/replacing ulnar collateral ligament
forearm
area from elbow to wrist
- includes radius + ulna + interosseus membrane (IOM)
proximal radioulnar joint
head of radius w/ radial notch of ulna
- pivot synovial
- anular ligament secures head of radius
muscles that pronate radioulnar joint
pronator teres (proximal) pronator quadratus (distal / by wrist)
muscle that supinate radioulnar joint
supinator
subluxation of radial head
complete dislocation of radial head
- may slide back into socket
- occurs mostly in children
**parents swinging child by arms (may be fun but could be dangerous)
distal radioulnar joint
head of ulna w/ ulnar notch of radius
- pivot synovial
- triangular ligament (articular disc)
ligaments of the distral radioulnar joint
dorsal radioulnar ligament
palmar radioulnar ligament
triangular ligament
“articular disc”
radius (broad end) w/ styloid process of ulna
interosseus membrane FCN
(1) connects radius + ulna
(2) separates anterior / posterior compartments
anterior antebrachial muscles (forearm)
superficial group (5) deep group (3)
flexor retinaculum
(1) covers tendon like a bracelet to keep muscles down
(2) prevent bulging
superficial group of anterior antebrachial muscles (forearm)
pronator teres palmaris longus flexor carpi radialis flexor carpi ulnaris flexor digitorum superficialis
**flexors
superficial group muscles of forearm
anterior antebrachial muscles (forearm)
pronator teres palmaris longus flexor carpi radialis flexor carpi ulnaris flexor digitorum superficialis
2nd layer of anterior antebrachial muscles (forearm)
flexor digitorum superficialis
2nd layer of anterior antebrachial muscles (forearm)
flexor digitorum superficialis
pronator teres
superficial group (1st layer) of anterior antebrachial muscles (forearm)
O: (humeral head) medial epicondyle humerus + common flexor tendon (ulnar head) coronoid process of ulna I: lateral radius A: pronate & flex forearm N: median nerve (C6 – C7)
palmaris longus
superficial group (1st layer) of anterior antebrachial muscles (forearm)
O: medial epicondyle humerus + common flexor tendon I: flexor retinaculum palmar aponeurosis A: flex hand @ wrist N: median nerve (C6 – C7)
- *absent in 14% of population
- *tendon = superficial to flexor retinaculum
flexor carpi radialis
superficial group (1st layer) of anterior antebrachial muscles (forearm)
O: medial epicondyle humerus + common flexor tendon
I: base of metacarpals #2 - 3
A: flex hand @ wrist + synergistic abduction w/ extensor carpi radialis longus & brevis
N: median nerve (C6 – C7)
**flex wrist radial side
flexor carpi ulnaris
superficial group (1st layer) of anterior antebrachial muscles (forearm)
O: (humeral head) medial epicondyle humerus + common flexor tendon
(ulnar head) olecranon & shaft ulna
I: pisiform + hook of hamate + base of metacarpal #5
A: flex hand @ wrist + synergistic adduction w/ extensor carpi ulnaris
N: ulnar (C8 – T1)
**flex wrist ulnar side
flexor digitorum superficialis
superficial group (2nd layer) of anterior antebrachial muscles (forearm)
O: (humeroulnar head) medial epicondyle humerus + common flexor tendon + coronoid process of ulna
I: 4 tendons divide into 2 slips each, insert onto middle phalanges digits #2 – 5
A: flex middle phalanges #2 – 5
N: median nerve (C7 – C8, T1)
- *largest superficial
- *4 tendons pass deep to flexor retinaculum thru carpal tunnel
deep group of anterior antebrachial muscles (forearm)
flexor digitorum profundus
flexor pollicis longus
pronator quadratus
**does not cross elbow
flexor digitorum profundu
deep group (3rd layer of anterior antebrachial muscles (forearm)
3rd layer of anterior antebrachial muscles (forearm)
flexor digitorum profundus
flexor pollicis longus
flexor digitorum profundus
deep group (3rd layer) of anterior antebrachial muscles (forearm)
O: shaft ulna + interosseous membrane
I: base distal phalanges #2 – 5
A: flex distal phalanges #2 – 5
N: ulnar nerve medial ½ (digits #4 – 5) + median nerve lateral ½ (digits #2 – 3)
- *4 tendons in carpal tunnel
- *holds fingers 2-5 together
flexor pollicis longus
deep group (3rd layer) of anterior antebrachial muscles (forearm)
O: shaft radius + interosseous membrane
I: base distal phalanx of thumb
A: flex thumb (distal phalanx)
N: median nerve (C8, T1)
- *pollex = thumb
- *tendon in carpal tunnel
pronator quadrauts
deep group (4th layer) of anterior antebrachial muscles (forearm)
O: distal shaft ulna
I: distal shaft radius
A: pronate forearm
N: median nerve (C8, T1)
**deepest forearm muscle
carpal tunnel
passageway btwn forearm + palmar hand
groupings of the posterior antebrachial group (forearm)
superficial group (7) deep group (5)
**extensors
features of the posterior antebrachial group (forearm)
extensor retinaculum
synovial tendon sheaths
**remember radial groove
function of synovial tendon sheaths
synovial membrane that decrease friction
superficial group of posterior antebrachial group (forearm)
brachioradialis extensor carpi radialis longus extensor carpi radialis brevis extensor digitorum extensor digiti minimi extensor carpi ulnaris anconeus
brachioradialis
superficial group - posterior antebrachial group (forearm)
O: lateral humerus
I: styloid process of radius
A: flex forearm
N: radial nerve (C5 – C6)
**only flexor (elbow) in posterior compartment
extensor carpi radialis longus
superficial group - posterior antebrachial group (forearm)
O: lateral humerus
I: distal base METACARPALS #2
A: extand hang @ wrist + synergistic abduction w/ flexor carpi radialis
N: radial nerve (C6 – C7)
extensor carpi radialis brevis
superficial group - posterior antebrachial group (forearm)
O: lateral epicondyle humerus + common extensor tendon
I: dorsal base metacarpal #3
A: extend hang @ wrist +synergistic abduction w/ flexor carpi radialis
N: radial nerve (C6 – C8)
extensor digitorum
superficial group - posterior antebrachial group (forearm)
O: lateral epicondyle humerus + common extensor tendon
I: dorsal surface phalanges #2 – 5
A: extend digits #2 – 5
N: radial nerve (C6 – C8)
extensor digiti minimi
superficial group - posterior antebrachial group (forearm)
O: lateral epicondyle humerus + common extensor tendon
I: dorsal surface digit #5
A: extend 5th digit
N: radial nerve (C6 – C8)
extensor carpi ulnaris
superficial group - posterior antebrachial group (forearm)
O: lateral epicondyle humerus + common extensor tendon
I: dorsal base metacarpal #5
A: extend hand @ wrist + synergistic adduction w/ flexor carpi ulnaris
N: radial nerve (C6 – C8)
anconeus
superficial group - posterior antebrachial group (forearm)
O: lateral epicondyle humerus
I: olecranon
A: extend forearm (assists triceps)
N: radial (C7 – C8)
**part of triceps brachii
deep group of posterior antebrachial muscles
abductor pollicis longus (APL) extensor pollicis longus (EPL) extensor pollicis brevis (EPB) extensor indices supinator
**not visible on arm models, only ADAM
muscles that act on thumb
deep group - posterior antebrachial muscles
abductor pollicis longus (APL)
extensor pollicis longus (EPL)
extensor pollicis brevis (EPB)
abductor pollicis longus (APL)
deep group - posterior antebrachial muscles
O: posterior radius + posterior ulna + interosseous membrane
I: dorsal base metacarpal #1
A: abduct + extend thumb
N: radial (C6 – C7)
**bottom
extensor pollicis longus (EPL)
deep group - posterior antebrachial muscles
O: posterior ulna + interosseous membrane
I: distal phalanx of thumb
A: extend thumb
N: radial (C6 – C8)
**top
extensor pollicis brevis (EPB)
deep group - posterior antebrachial muscles
O: posterior radius + interosseous membrane
I: proximal phalanx of thumb
A: extend thumb
N: radial (C6 – C7)
**bottom
extensor indices
deep group - posterior antebrachial muscles
O: posterior ulna + interosseous membrane
I: phalanges digit #2
A: extend index finger
N: radial (C6 – C8)
supinator
deep group - posterior antebrachial muscles
O: lateral epicondyle humerus + anular ligament
I: lateral proximal 1/3 radius
A: supinate forearm
N: radial C6
anatomical snuff box
the indent on the dorsal side of hand by the thumb when it is abducted/flexed
boundaries of the anatomical snuff box
tendons of:
- extensor pollicis longus
- extensor pollicis brevis
- abductor pollicis longus
contents in the anatomical snuff box
radial artery
radial styloid process
scaphoid
trapezium
