Chapter 4 - Upper Extemity
what is the amount of elbow flexion required for the trauma lateral projection (coyle method) to demonstrate to coronoid process?
80 degrees
how many metacarpal (palm) bones are in the hand?
5
a radiographic procedure that uses contrast media injected into the joint capsule to visualize soft tissue pathology of the wrist, elbow and shoulder joints
arthrography
which is the largest carpal bone?
capitate
the similar structure on the lateral aspect of the distal humerus is called?
capitulum
what is the intermediate double arc, consisting of the outer ridges?
capitulum and trochlea
which special projection(s) of the elbow should be performed instead of the routine AP if the patient's elbow is tightly flexed and cannot be extended at all?
central ray perpendicular to humerus and central ray perpendicular to forearm (acute flexion projection)
a patient with a possible fracture of the radial head enters the ER. when the tech attempts to place the arm in the AP oblique lateral rotation position, the patient is unable to extend or rotate the elbow laterally. which other position can be used to demonstrate the radial head and neck without superimposition of the proximal ulna?
coyle method for radial head
ellipsoidal joints are classified as freely moveable, or____________, that allow movement in ____________ directions.
diarthrodial, 4
a radiograph of a PA oblique projection of the hand reveals that the fourth and fifth metacarpals are superimposed. which specific positioning error is involved?
excessive lateral rotation
which positioning error is involved if a majority of the carpal bones are superimposed in a PA oblique wrist?
excessive lateral rotation from PA
which preferred lateral position of the hand best demonstrates the phalanges without excessive superimposition?
fan lateral
where is the central ray centered for an AP projection of the thumb?
first MCP joint
what are the four directions ellipsoidal joints can move?
flexion, extension, abduction, and adduction
what is the name of the hooklike process extending anteriorly from the hamate?
hamulus
the elbow should be generally flexed ________ degrees for the routine positions of the wrist.
90
the hand and wrist form __________ degree angle to the forearm with the carpal bridge projection?
90
which routine projections are required for the study of the forearm?
AP and lateral
a patient with a trauma injury enters the ER with an evident colles' fracture. which positioning routine should be used to determine the extent of the injury?
AP and lateral forearm to include the wrist
what is the proper name for the position referred to as the "ball-catcher's position"?
norgaard method
which projection of the thumb is achieved naturally by placing the palmar surface of the hand in contact with the cassette?
oblique
the "ball-catcher's position" is commonly used to evaluate for early signs of?
rheumatoid arthritis
which is the most commonly fractured carpal bone?
scaphoid
the two important fat stripes or bands around the wrist joint are?
scaphoid and pronator fat stripes
which routine projection of the elbow best demonstrates the radial head, neck, and tuberosity with slight (if any) superimposition of the ulna?
AP oblique with 45 degree lateral rotation
which alternative projection to the routine PA wrist best demonstrates the intercarpal joint spaces and wrist joint?
AP projection with hand slightly arched
how much of the metacarpals should be included for PA projections of the digits?
the distal aspect of the metacarpals
the best position to evaluate the posterior fat pads of the elbow joint is?
lateral, flexed 90 degrees
a sesamoid bone is frequently found adjacent to the _________ joint of the thumb.
metacarpophalangeal
a patient with a metallic foreign body in the palm of the hand enters the ER. which specific positions should be used to locate the foreign body?
PA and lateral-in-extension projection
which routine projections best demonstrate the scaphoid fat pad?
PA and oblique wrist
which special projection of the wrist best demonstrates the interspaces on the ulnar side of the wrist between the lunate, triquetrum, pisiform, and hamate bones?
PA projection with radial deviation
how many phalange bones are in the hand?
14
what degree of central ray angulation is required for this projection?
15 degrees
a PA axial scaphoid projection of the wrist using 15 degree distal central ray angle and ulnar flexion was performed. the resultant radiograph reveals that the scaphoid bone is foreshortened. how must this projection be modified to produce a more diagnostic image of the scaphoid?
15 degrees proximally, toward the elbow
what is the routine positioning routine for the 2nd through 5th digits of the hand?
PA, oblique, and lateral
how much central ray angulation to the long axis of the hand is required for the carpal canal (tunnel) projection?
25-30 degrees
how much central ray angulation from the long axis of the forearm is required for the carpal bridge?
45 degrees
how much and in which direction should the central ray be angled for the trauma axial lateral projection (coyle method) involving the coronoid process?
45 degrees away from the shoulder
how much and in which direction should the central ray be angled for the trauma axial lateral projection (coyle method) involving the radial head?
45 degrees toward the shoulder
in the anatomic position, which of the bones of the forearm is located on the medial side?
ulna
what is the name of the two special turning or bending positions of the hand and wrist that demonstrate medial and lateral aspects of the carpal region?
ulnar and radial deviation
of ulnar and radial deviation, which one is most commonly performed to detect a fracture of the scaphoid bone?
ulnar deviation
a radiograph of an AP elbow projection reveals considerable superimposition between the proximal radius and ulna. which specific positioning error in involved?
the elbow is rotated medially
a radiograph of a lateral projection of the elbow reveals that the humeral epicondyles are not superimposed and the trochlear notch is not clearly demonstrated. which specific type of positioning error has occurred?
the forearm and humerus are not on the same horizontal plane
where is the central ray centered for a PA projection of the hand?
third MCP joint
the articular portion of the medial aspect of the distal humerus is called?
trochlea
what is the FIRST and SMALLEST of the arcs?
trochlea sulus (groove)
the third arc, which is part of the ulna is the?
trochlear notch
during the PA axial scaphoid projection with central ray angel and ulnar flexion, the central ray must be angled __________ degrees _______________
10 to 15 degrees, proximally
how much are the hands and wrists elevated from the IR for the modified stecher method?
20 degrees
how much is the upper limb rotated for a lateral (rotation) oblique projection of the elbow?
45 degrees
which projection of the elbow best demonstrates the coronoid process in profile?
AP oblique with 45 degree lateral rotation
which special projection of the wrist helps rule out abnormal calcification in the carpal sulcus?
gaynor-heart projection
what are the parts of each phalanx, starting distally
head, body, and base
the depression located on the posterior aspect of the distal humerus is?
olecranon fossa
to properly position the patient for an AP projection of the elbow, the epicondyles must be____________ to the IR
parallel
in the anatomic position, which of the bones of the forearm is located on the lateral (thumb) side?
radius
a radiograph of a PA projection of the second digit reveals that phalanges are not symmetrical on both sides of the bony shaft. which positioning error is involved?
rotaion
what is the only difference among the four radial head lateral projections of the elbow?
rotational position of hand and wrist
what are two radiographic criteria used to determine whether rotation is present on the PA projection of the digits?
symmetric appearance of both sides of the shafts of phalanges and distal metacarpals equal amounts of tissue on each side of the phalanges
a minimum of ______ inch(es) (__________cm) of the forearm should be included radiographically for a PA projection of the hand...
1 inch (2.5cm)
a patient with dislocated elbow enters the ER. the patient has the elbow tightly flexed and is careful not to move it. which specific positioning routine can be used to determine the extent of the injury?
2 AP projections with acute flexion and a lateral projection
How many bones TOTAL are in the hand?
27
how much rotation is required for an oblique projection of the wrist
45 degree
how many carpal bones (wrist) are in the hand?
8
which IR size should be used for a thumb projection?
8 X 10
in a radiographic study of the forearm, the proximal radius crossed over the ulna in the frontal projection. which specific positioning error led to this outcome?
PA projection was performed rather than a AP
a bennett's fracture involves?
base of the first metacarpal
What are the three parts of the metacarpals, starting proximally?
base, body, and head
how does the forearm appear radiographically if pronated for a posterior PA projection?
the proximal radius crosses over the ulna
a radiograph of an AP oblique elbow with lateral rotation reveals that the radial tuberosity is superimposed on the ulna. in what way must this position be modified during the repeat exposure?
increase lateral rotation of the elbow to separate the radius from the ulna
name the joint between the proximal and distal phalanges of the first digit.
interphalangeal (IP) joint
why is the AP projection of the thumb recommended instead of the PA?
it produces an decreased OID and increased resolution
which lateral projection of the hand best demonstrates a possible foreign body in the palm of the hand?
lateral in extension
which routine projection best demonstrates the pronator fat stripe?
lateral wrist
name the joint between the metacarpals and the phalanges
metacarpophangeal (MCP) joint
a patient with a possible fracture of the trapezium enters the ER. the routine projections do not clearly demonstrate a possible fracture. which other special projection can be taken?
modified robert's method
which special positioning method can be performed to demonstrate a Bennett's fracture?
modified robert's method
if the patient cannot fully extend the elbow for the AP projection, what alternative projection(s) should be performed?
one with forearm parallel to IR and one with the humerus parallel to IR
where is the central ray centered for a PA oblique projection of the second digit?
proximal interphalangeal (IP) joint
which joint permits the forearm to rotate during pronation?
proximal radioulnar joint
what are the three portions of the fingers (2nd-5th digit)?
proximal, middle, distal
which ligament of the wrist extends from the styloid process of the radius to the lateral aspect of the scaphoid and trapezium bones?
radial collateral ligament