Upper Limb Anatomy

Front 1

what are the functions of the clavicle (3)?

Back 1

1. rigid suspension for scapula and free limb allowing maximum freedom of motion

2. protection to upper limb's neurovascular bundle by forming one of the bony boundaries of the cervico-axillary canal

3. transmits shocks from upper limb to axial skeleton

Front 2

how is the clavicle different to other long bones?

Back 2

no medullary cavity - spongy (trabecular) bone with shell of compact bone

Front 3

what are the articulations and shapes of the the articulations of the clavicle?

Back 3

triangular articulation with manubrium of sternum at the SC joing

flat where articulates w acromion of scapula at the AC joint

Front 4

why is the inferior surface of the clavicle rough?

Back 4

because of strong ligamentous binding to 1st rib near sternal end and suspension of scapula near acromial end at conoid tubercle

Front 5

how does the coracoclavicular ligament relate to the clavicle?

Back 5

the conoid ligament is the medial part of the coracoclavicular ligament and attaches at the conoid tubercle

the trapezoid ligament is the lateral part of the coracoclavicular ligament and attaches at the trapezoid line

Front 6

what function does binding the clavicle to the 1st rib serve?

Back 6

limits elevation of the shoulder

Front 7

what ribs does the scapula overlie?

Back 7

2nd-7th

Front 8

SCAPULOTHORACIC JOINT

Back 8

*more needed when do muscles

Front 9

what are the important attachments of the scapular spine? (3)

Back 9

shoulder joint (acromion articulating with humerus)

AC joint (acromion articulates w clavicle)

deltoid tubercle - medial point of attachment of the deltoid

Front 10

what divides the posterior scapula? into what?

Back 10

the scapular spine - into supra and infraspinous (larger) fossae

Front 11

what is the subscapular fossa?

Back 11

the concave costal surface of the scapula

Front 12

how are the scapula and the arm balanced? what is the suspending structure and where is it placed?

Back 12

glenohumeral joint is almost directly inferior to AC joint

the suspending structure is the coracoclavicular ligament, placed between the two masses

Front 13

what forms the head of the scapula?

Back 13

the glenoid cavity, which is the thickest part of the scapula

Front 14

what are the articulations of the humerus?

Back 14

head articulates with glenoid cavity of scapula

capitulum articulates w head of radius, troachlea articulates with ulna

Front 15

what are the main features of the the proximal humerus (5)

Back 15

head
surgical and anatomical neck
greater and lesser tubercles

Front 16

what distinguishes the surgical from the anatomical neck of humerus?

Back 16

anatomical neck formed by groove circumscribing the head & separating it from greater and lesser tubercles. Indicates line of attachment of glenohumeral joint capsure

Surgical neck of humerus is a common site of fracture & is the narrow part of the humerus distal to head and tubercles

Front 17

what is the function of the humerus' intertubercular groove?

Back 17

to provide protected passage for the slender tendon of long head of biceps

Front 18

how are the greater and lesser tubercles oriented on the humerus?

Back 18

greater tubercle - lateral margin of humerus

lesser tubercle projects anteriorly

Front 19

what are the two prominent features of shaft of humerus?

Back 19

lateral deltoid tuberosity (deltoid attachment)

oblique radial groove (posterior) for radial nerve and deep artery of arm as they pass anterior to long head & between medial and lateral heads of triceps brachii

Front 20

what are the distal sites of humerus for muscle attachment?

Back 20

lateral epicondyle for extendors

medial epicondyle for flexors

Front 21

what makes up the humeral condyle?

Back 21

trochlea and capitulum

olecranon, coronoid and radial fossae

Front 22

what are the articular surfaces of the distal humerus?

Back 22

capitulum (L. little head) - laterally articulates w head of radius

trochlea (L. pulley) - medial, pulley shaped, articulates w trochlear notch of ulna

Front 23

what are the fossae of the distal humerus? in what positions are they occupied?

Back 23

anteriorly - radial (head of radius in full forearm flexion) and coronoid (coronoid process of ulna during full flexion of elbow)

posteriorly - olecranon fossa - for olecranon of ulna in full elbow extension

Front 24

what does the pivoting ability of the radius around the ulna allow the hand to do and in what circumstance?

Back 24

supination and pronation become possible, allowing the hand to rotate when the elbow is in full flexion

Front 25

what is the function of the ulna?

Back 25

stabilises the forearm

Front 26

what is the trochlear notch of the ulna and what hardware store item does it resemble?

Back 26

the olecranon & coronoid process which in profile resemble a crescent wrench gripping the humeral trochlea

Front 27

what is the surface anatomy of the ulnar olecranon and what is its function?

Back 27

point of the elbow, is a short lever for elbow extension

Front 28

what lies inferior to the coronoid process?

Back 28

tuberosity of ulna (brachialis tendon attachment)

Front 29

where do the ulna and radius articulate

Back 29

proximally - radial notch of ulna (lateral side of coronoid process) with head of radius

distall - ulnar notch on radius with head of ulna

Front 30

what articulation does the ulna have with the wrist?

Back 30

none, it doesn't reach that far

Front 31

does the ulna get thicker or thinner as it progresses distally?

Back 31

thinner

Front 32

what are the proximal articulations of the ulna?

Back 32

trochlea of humerus (proximally)
head of radius (laterally)

Front 33

how does the shaft of the radius differ from that of the ulna?

Back 33

enlarges as it passes distally

Front 34

how many sides does a transverse section of the distal end of radius have? what are they?

Back 34

four
medial - ulnar notch
lateral - styloid process
superior & posterior nil special articulation, upper border of lunate & scaphoid articulations

dorsal tubercle of radius projects dorsally

Front 35

what relationship between ulnar and radial styloid process is clinically important & why?

Back 35

radial styloid process is larger & extends further distally which is important to assess when there is a fractured radius or ulna

Front 36

what is the shape of the cross section of radial & ulna shaft?

Back 36

triangular with a rounded, superficially directed base & acute, deeply directed apex

Front 37

what are the attachments and orientation of the interosseous membrane? what is its function?

Back 37

attach to the apices of the ulnar/radial cross sectional trianges (interosseous border)

most fibers run an oblique course, passing inferiorly from the radius as they extend medially to the ulna

they are positioned to transmit forces received by radius (via the hands) to the ulna for transmission to humerus

Front 38

what is the point of having small bones of the wrist?

Back 38

flexibility to the hand

Front 39

what is the general organisation of the bones of the wrist?

Back 39

8 bones
3 base bones supporting 4 bones which support the carpals

Front 40

how does the osteology of the ulnar fingers support their function (which is what?)

Back 40

power grasping
pinky & fourth share one metacarpal (fused from general vertebral model where each had its own metacarpal)

third finger has third metacarpal which has enlarged to form capitate

ie strong & stable

all three work together in making a fish & share a single palmar skin crease

Front 41

what is the function of having small carpal bones?

Back 41

flexibility of the wrist - the two layers glide on each other & each bone glides on the one next to it

Front 42

what are the largest carpal bones?

Back 42

captitate - largest carpal bone

schaphoid - largest carpal in proximal row

Front 43

what are the proximal carpal bones (from lateral to medial?)

Back 43

scaphoid (boat)
lunate (moon)
triquetrum (three cornered)
pisiform (pea)

Front 44

what are the distal carpal bones (lateral to medial)

Back 44

trapezium (table)
tapezoid
capitate (head)
hamate (little hook)

Front 45

what distinguishes the third metacarpal from the others?

Back 45

styloid process on lateral side of base

Front 46

how is the arrangment of the thumb's phalanges different to the others?

Back 46

has two rather than three

Front 47

by what age are ossification centers of all carpal bones visible?

Back 47

11

Front 48

from how many centres does each carpal ossify postnatally?

Back 48

one

Front 49

why is it easier to deviate the hand to the ulnar side than the radial side?

Back 49

because the radial styloid extends more distally than the ulnar styloid

Front 50

which is the first bone to ossify?

Back 50

clavicle

Front 51

which bones of the upper limb are not palpable?

Back 51

lunate
trapezoid

Front 52

where do the large vessels and nerves to the upper limb pass the clavicle?

Back 52

posteriorly to the anteriorly convex medial section

Front 53

what structures form the rounded curve of the shoulder?

Back 53

humerus (in glenoid cavity) & deltoid

Front 54

in the anatomical position, what vertebral level does the superior angle of the scapula lie at?

Back 54

T2

Front 55

in the anatomical position, which vertebral level does the inferior angle of the scapula lie?

Back 55

T7, near inf border of 7th rib & 7th intercostal space

Front 56

draw the relationship between clavicle, scapula and humerus

Back 56

drawing

Front 57

draw the anterior and posterior surfaces of the scapula

Back 57

drawing

Front 58

draw the lateral view of the scapula

Back 58

drawing

Front 59

draw the anterior and posterior views of the distal humerus

Back 59

drawing

Front 60

draw the proximal end of the ulna and a side profile of humerus, radius & ulna in flexion & extension

Back 60

drawing

Front 61

draw the relationship between ulna and radius (anterior & posterior views)

Back 61

drawing

Front 62

draw the anterior view of the hand bones

Back 62

drawing

Front 63

draw the posterior view of the hand bones

Back 63

drawing

Front 64

what are the four muscles that move the pec girdle?

Back 64

pec major
pec minor
subclavius
serratus anterior

Front 65

which muscle covers the superior part of the thorax?

Back 65

pec major

Front 66

what are the two heads of the scapula and how are they different?

Back 66

clavicular & sternocoastal

sternocostal much bigger

Front 67

what anatomical landmarks involve pec major?

Back 67

inferior border of sternocostal head forms the anterior axillary fold

pec major + deltoid forms narrow deltopectoral groove where the cephalic vein runs; and superiorly diverge to form the clavipectoral (deltopectoral) triange

Front 68

what movements can pec major do when the two parts act together? seperately?

Back 68

together - powerful adduction & medial rotation of the arm

seperately - clavicular head flexes humerus

sternocostal head extends humerus back from flexed position

Front 69

how do we test the clavicular head of pec major?

Back 69

abduct arm 90 degrees
then move arm anteriorly against resistance

if normal, clavicular head can be seen & palpated

Front 70

how do we test sternocostal head of pec major?

Back 70

abduct arm to 60 degrees

then adduct against resistance

if normal, sternocostal head can be seen & palpated

Front 71

what are the attachments of pec minor?

Back 71

base - fleshy slips to anterior ends ribs 3-5 near costal carilages

apex (distal) - coracoid process of scapula

Front 72

what is the main function of pec minor?

Back 72

stabilise the scapula

used when stretching upper limb forward to an object just out of reach

elevates ribs for deep inspiration when pec girdle fixed or elevated

useful anatomical & surgical landmark for structures in the axilla (eg axillary artery)

forms a bridge (with coracoid process) under which vessels & nerves pass to the arm

Front 73

what is the role of subclavius?

Back 73

anchors & depresses the clavicle, stabilizing it during movements of the upper limb

Front 74

how is subclavius protective?

Back 74

affords some protection to subclavian vessels superior trunk of brachial plexus if clavicle fractures

helps resist the tendency for clavicle to dislocate at SC joint (eg during tug of war)

Front 75

for what is the serratus anterior muscle named?

Back 75

serratus = saw

Front 76

what is the "boxer's" muscle? why?

Back 76

serratus anterior

strong protractor of the scapula & used for punching or reaching anteriorly

Front 77

which muscle holds the scapula against the thoracic wall when pushing against resistance (eg pushups?)

Back 77

serratus anterior

Front 78

what are the jobs of the inferior part of serratus anterior?

Back 78

rotates scapula & elevates the glenoid cavity to allow the arm to be lifted above the shoulder

anchors the scapula closely to the thoracic wall, allowing other muscles to use it as fixed bone for mevements of the humerus

Front 79

how do we test serratus anterior? or the function of WHICH nerve that supplies it?

Back 79

hand of outstretched limb is pushed against a wall - if normal, will be able to see & palpate several digitations of the muscle

supplied by long thoracic nerve