lecture 5 Flashcards
Pectoral Girdle and Upper Extremity
where is the pectoral girdle and what does it attach too?
it attaches upper limb to axial skeleton and is composed of two bones
what comprises the pectoral girdle?
the clavicle and the scapula
what are the anatomical relationships of the clavicle?
1) it lies horizontally anterior and superior to the bony thorax
2) its superior to the first rib
3) it articulates medially with manubrium (sternoclavicular joint) and laterally with the acromial process of the scapula (acromioclavicular joint)
it lies horizontally anterior and superior to the?
bony thorax
what is the clavicle also superior too?
the first rib
what does the clavicle articulate medially and laterally with?
medially with the manubrium (*sternoclavicular joint) and laterally with the acromial process of the scapula *(acromioclavicular joint)
what are the features of the clavicle?
acromial extremity, sternal extremity, conoid tubercle and costal tuberosity
where is the conoid tubercle attachment site?
on the conoid ligament to coracoid process of the scapula
what is the costal tuberosity attachment site?
attachment for the rhomboid ligament which connects inferiorly to the 1st rib
what is the scapula?
triangular bone that forms the shoulder blade
what are the anatomical relationships of the scapula?
it lies in posterior superior thorax, between levels of 2nd and 7th ribs, medial border parallel to and approx 2-3 inches form vertebral column
what are the features of the scapula?
it has medial, lateral and superior borders, superior and inferior angles, scapular notch, spine, acromion, coracoid, glenoid cavity, fossae
where is the scapular notch?
located on the superior border and allows passage of supra scapular nerve
where is the spine?
the ridge running diagonally on the posterior surface
where is the acromion?
flattened lateral end of spine, the superior most point of the bony shoulder and it articulates with the clavicle
what is the acro?
top or summit
what attaches to the coracoid process?
site of muscle attachment
what coracoid (kokakodes) also translate too?
like a crow’s beak
what articulates with the glenoid cavity (fossa)?
it articulates with head of the humerus
what are the fossae associated with the scapula?
they serve as attachment points for shoulder muscles and each is decriptively named
name the fossae associated with the scapula?
infraspinatus fossa, supraspinatus fossa, sub scapular fossa
what is the humerus?
the long bone of the arm
what are the anatomical relationships of the humerus?
it articulates proximally with the glenoid fossa and distally with the radius and ulna
what does the humerus articulate proximally with?
the glenoid fossa
what does the humerus articulate distally with?
the radius and ulna
name the features of the proximal humerus?
greater tubercle, lesser tubercle, inter tubercular groove, anatomical neck, surgical neck
describe the greater tubercle?
lateral most bony landmark of shoulder
what is significant about the anatomical neck?
its the site of the epiphyseal plate
what is significant of the surgical neck?
common site of fracture
what are the features of the diaphysis?
deltoid tuberosity and the radial groove
what should be noted about the radial groove?
its where the radial nerve runs through
what are the features of the distal epiphysis?
medial and lateral epicondyles, capitulum, trochlea, coronoid, radial fossa, olecranon fossa
what do the medial and lateral epicondyles attache too?
they are the attachment sites for forearm muscles
what is the capitulum also known as?
small head
describe the capitulum and where it articulates?
rounded surface that articulates with head of radius
describe the trochle and its articulation?
spool shaped articulating with ulna
coronoid fossa is also known as the ____?
so krone for crown shaped
where is the coronoid located?
its a depression that receives coronoid process of ulna when forearm is flexed
what is the radial fossa?
depression that receives head of radius when forearm is flexed
what is the olecranon fossa
depression that receives olecranon of ulna when forearm is extended; prevents the arm from hyperextending
what are the bones of the forearm?
ulna, radius
describe the forearm
connected via interosseous membrane providing attachment for deeper muscles of the forearm
describe the ulna?
medial bone of the forearm and has proximal and distal features
what are the proximal features of the ulna?
olecranon process, trochlear notch, radial notch
what is the olecranon process?
forms the prominence of the elbow
what does the trochlear notch articulate with?
it articulates with the trochlea of the humerus to form the portion of the elbow joint
what does the radial notch articulate with?
it articulates with the head of the radius to form proximal radioulnar joint
what are the distal features of the ulna?
its a head with styloid process
describe the radius?
lateral bone of the forearm
what are the proximal features of the radius?
head and radial tuberosity
describe the head of the radius?
disc shaped that articulates with the capitulum of the humerus and radial notch of the ulna to form the portion of the elbow joint
describe the radial tuberosity of the radius?
its the attachment point for the biceps brachii
what does the distal portion of the radius articulate with?
so the distal features of the radius comes as a concave surface articulating with lunate, scaphoid and triquetrum to form the radiocarpal or wrist joint
what is another distal feature of the ulnar notch?
it articulates with the head of the ulna to form distal radioulnar joint
how many regions does the hand consist of ?
three regions
name the regions of the hand?
carpus, metacarpus, and phalanges
what is the carpus?
comprised of short and sesamoid bones of the wrist
what are the components of the carpus?
scaphoid, lunate, triquetrum, pisiform, hamate, capitate, trapezoid, trapezium
what pneumonic can we use to remember the bones of the carpum?
So Long To Pinky, Here Comes The Thumb
scaphoid nickname?
skiff or boat
lunate nickname?
moon
triquetrum nickname?
three shaped
hamate nickname?
little hook
capitate nickname?
head
trapezoid nickname?
4 sided
what is significant about the pisiform?
sesamoid bone within the tendon of the flexor carpi ulnaris and does not develop until approx 12 years of age
the hamate can be considered a landmark for the carpus of the hand?
yes
what is the metacarpus of the hand?
comprised of long bones of the palm of the hand
the digits are numbered, what number is the thumb?
the thumb is one
what are the phalanges?
they are the long bones of the finger
what are the common fractures of the upper extremities
clavicle, scapula, humerus, radius, and hand
how do fractures of the clavicle occur?
often due to indirect force of falling on an outstretched arm, its the weakest point of juncture, weight of the limb causes depression of shoulder and overriding of fractured ends, also misrepresented as fractures due to genetic defect
with respect to the clavicle, where is the most common point of the fracture?
in the S region and when it breaks, it slides in together not out
so if the fracture of clavicle can be misdiagnosed as a genetic defect, how can this be?
a genetic defect of 1st degree and 2nd degree ossification centers not fusing and so defect misdiagnosis occurs normally by age 31
how can the fracture of the scapula occur?
rarely fractured outside of severe trauma and treatment require little treatment due to covering of muscles
how can fractures of the humerus occur?
can occur in multiple sites and nerve damage always needs to be considered
what is the most common fracture of the humerus seen in elderly people?
fractures of the surgical neck even with low impact falls
name some types of fractures that affect the humerus?
impacted fracture, avulsion fracture, transverse fracture, spiral fracture, intercondylar fracture
describe the impacted fracture?
fragment of one end driven into spongy bone of the other end and so its a stable fracture allowing passive movement of arm with little pain
describe the avulsion fracture of the greater tubercle?
small part of tubercle with attached tendon avulsed, like a sliver take off to make an arrowhead
what is the transverse fracture of the humerus?
result of a direct blow and the deltoid carries proximal fragment laterally
what is the spiral fracture of the humerus?
overriding oblique ends result in bone shortening resulting in the fall of an outstretched arm
what is the intercondylar fracture of the humerus?
results from severe fall on flexed elbow and so the olecranon acts as wedge between medial and lateral condyle
the humerus has a strong periosteum surrounded by muscle and bone fragments untie well, T/F?
true
what is the colles fracture of the radius?
it is the distal fragment of the radius dislocated dorsally
how does the colles fracture result?
dinner fork deformity, avulsion of styloid process of ulna often a co-occurrence and is produced by the hyperextension of the hand while breaking a fall; common in patients with osteoporosis
where do fractures of the hand result?
scaphoid, hamate, metacarpals and phalanges
how does the scaphoid fracture of the hand result?
by breaking fall on abducted and or hyperextended hand
describe the pain of a scaphoid hand?
immediate but fracture may not initially show on radiograph until 10-14 days later likewise with other carpals as well
what is vascularization of the scaphoid like?
poor and so slow to heal with increased risk of vascular necrosis
how does a hamate fracture of the hand occur?
most commonly fractured in sports using a racket, bat, club
which nerve can be affected by a hamate fracture?
the ulnar nerve leading to loss of innervation to intrinsic hand muscles like loss of grip
can hamate fracture affect action?
yes, action of attached muscles can inhibit re union of fractures and often requires surgical intervention for healing
how can the metacarpals and phalanges be affected?
by crushing or hyperextension injuries
