Chapter 4 Upper Extremities
What three positions are used to demonstrate the hand in the lateral projection Merrill's?
1) ulnar surface down, hand extended or in natural flexion 2) radial surface down, hand extended 3) ulnar surface down, finger in "fan lateral"
Which parts of the upper extremity should be on the same plane for a lateral projection of the elbow?
1) wrist joint 2) elbow joint 3) shoulder joint
What are the possible hand positions for the lateral projection of the hand?
Extension Flexion Fan/feathered
True or False: there should be no OID when doing the oblique finger projection
False: some OID is inevitable to keep the finger extended and parallel to the IR
Soft tissue radiographs of the elbow in the lateral position are often ordered to demonstrate:
Fat Pads: The anterior and Supinator fat pad are Seen on negative x-rays. If the posterior fat pad arising From the olecranon fossa is Visible there is a problem in the elbow.
What is the difference between the Norgaard method and the "Ball catcher" bilateral hands?
For the ball catcher the hands are in natural flexion and they are extended for the Norgaard
What anatomy should be included for the fingers 2-5 on the routine projections (PA. Oblique, and Lateral)
From the tip of the distal phalanx and its surrounding soft tissue to the head of the metacarpal for (2-5) (to the trapezium for 1 (thumb)
What is a Colle's fracture?
Fx with posterior displacement of the distal Radius
What structure is shown "in profile" on an AP projection of the humerus?
Greater tubercle and humeral head
What position is the hand placed in to achieve the PA oblique projection of the thumb?
Hand in PA position (palmar surface down) with the thumb extended and the hand in slight ulnar deviation
What position is the hand in to achieve a lateral projection of the thumb?
Hand in PA with palmar surface down with the fingers flexed into a natural arch position, adjust the flexion to rotate thumb into true lateral
What structures are demonstrated in profile in the AP projection of the humerus?
Humeral head and Greater Tubercle in profile laterally
How should the arm be positioned to produce and adequate image of the forearm lateral projection?
Humerus and forearm parallel to IR Elbow flexed 90 degrees Wrist in true lateral
Stecher suggests an alternative to the 20 degree elevation of the IR and wrist if not achievable, what is it?
IR and wrist parallel to the table with a 20 degree angle toward the elbow
If the elbow is in full flexion is the coronoid process in or out of the coronoid fossa?
In its fossa when flexed and out when extended
The posterior fat pad lies in the:
In the Olecranon fossa
Which projection is the primary projection used to demonstrate anterior or posterior displacement of fractures of the hand or wrist?
Lateral Projection
What lateral hand position is used to demonstrate soft tissue and foreign bodies?
Lateral in extension
What lateral hand position is used to demonstrate metacarpal fractures (boxer's fracture)
Lateral in natural flexion
What structures are demonstrated in the lateral projection of the Elbow?
Lateral projection of elbow joint: distal arm and proximal forearm Olecranon process in profile out of the Olecranon fossa
Which tubercle is shown "in profile" on a lateral projection of the humerus?
Lesser Tubercle
Which tubercle of the proximal humerus should be demonstrated in profile in the Later projection of the humerus?
Lesser tubercle in profile
What are the possible projections for the lateral hand?
Mediolateral (Radial side down) Or Lateromedial (ulnar side down)
Which lateral projection of the humerus will provide a true lateral elbow w/out OID of the proximal Humerus
Mediolateral projection with patient PA
What positioning error can cause closing of the joints when doing finger images?
Not keeping the finger extended and parallel to the IR
Which of the structure is shown "in profile" on a lateral projection of the elbow?
Olecranon Process (out of its fossa)
Which parts of the upper extremity should be in contact with the tabletop for a PA projection of the wrist?
1) arm 2) axilla 3) forearm All Three should be parallel to IR
Which carpal is the largest?
Os Magnum or Capitate
If the elbow is in full flexion is the olecranon process in or out of the olecranon fossa?
Out of the fossa; The olecranon process is in the olecranon fossa when the elbow is extended.
Medially the radial head articulates with what?
The radial notch of the Ulna
What is the Bridgman method for the PA Axial scaphoid?
The stecher with ulnar deviation
Which carpals are demonstrated with little superimposition in the PA Oblique projection?
The trapezium and the scaphoid, the lateral side
Describe positioning and central ray location for the PA Axial Projection Stecher method for the scaphoid:
Wrist PA on the IR that is elevated a 20 degree wedge sponge. (fingers on the higher end) CR perpendicular to the table directed to the scaphoid
List the Distal row of Carpals
hamate, capitate, trapezoid, trapezium
Which lateral projection should be done on the 4th and 5th fingers?
lateromedial
Which lateral projection should be done on fingers 2 and 3?
mediolateral
The posterior fat pad lies in the:
olecranon fossa
Rotating the arm medially for a lateral projection of the humerus will place the epicondyles:
perpendicular with the plane of the IR
List the Proximal row of Carpals
pisiform, triquetrum, lunate, scaphoid
What structures are demonstrated in the AP external oblique projection of the elbow?
Radial head and neck free of superimposition
What structures does the trauma lateral projection (Coyle method) of the elbow demonstrate?
Radial head, neck and tuberosity should be in profile, free of superimposition except for a small part of the coronoid process Demonstrates fractures and dislocations of the elbow, especially the radial head
Which carpal is the most commonly fractured?
Scaphoid
What structures are demonstrated in the PA projection ulnar deviation of the wrist?
Scaphoid at right angles to the central ray to project it without self superimposition Corrects foreshortening of the scaphoid that occurs with perpendicular central ray and opens the spaces between the adjacent carpals
How should the arm be positioned to produced an adequate image of the elbow in the lateral projection?
Seat patient at end of table with elbow flexed 90 degrees The entire limb is parallel to the IR and the hand & wrist are in lateral position (IF patient has a muscular forearm build up wrist to keep entire arm parallel)
What is the patient position for the PA Projection of the wrist?
Seated at the end of the table the the axilla in contact with the table. Flexing the forearm 90 degrees and keeping the entire arm parallel to the table.
How should the arm be positioned to produce an adequate image of the elbow AP Projection?
Seated at the end of the table with entire arm (humerus to wrist) parallel to the table Elbow extended, epicondyles at equidistance to the IR and the Hand supinated
How will the radial head, neck and tuberosity be demonstrated in the AP elbow projection?
Slightly superimposed over the ulna.
how are digits numbered
Starting on the lateral side (in anatomical position) : the thumb is 1 and the pinky is number 5
Which fat pad lies parallel with the anterior aspect of the proximal radius?
Supinator fat pad
What breathing technique should be used on a humerus PA or Lateral projection?
Suspend respiration
What breathing techniques should be used for an AP projection of the humerus?
Suspended Respiration (Shallow or full inspiration is used on the transthoracic for trauma)
The intercarpal joints are of what type?
Synovial Gliding
The 10 joints of the upper limb are all:
Synovial and freely movable, they just differ in the synovial movement classifications. (ex. shoulder is ball and socket where the elbow is hinge)
The radiocarpal joints are of what type?
Synovial ellipsoidal
The interphalangeal joints are of what type?
Synovial: Hinge: freely movable
The metacarpophalangeal of what type?
Synovial: ellipsoidal: Freely movable: flexion, extension Adduction and abduction
Which projection best demonstrates the carpal interspaces?
The AP projection due to the oblique direction of the interspaces, they are more closely parallel with the divergence of the rays
Which fossa is on the anterior aspect of the humerus (coronoid or olecranon)?
The Coronoid Fossa. The olecranon is on the posterior aspect
Superiorly, the radial head articulates with the:
The capitulum
What makes up the carpal tunnel?
The carpal sulcus and the Flexor retinaculum The median nerve travels through this canal
Navicular or scaphoid
The first bone located on the proximal row and lateral side of the wrist is called the:
The CR for a PA projection of the wrist is directed to the:
The midcarpal area
What must be included on the AP and lateral projection of the forearm?
Radius Ulna Elbow joint Wrist joint (at least the proximal row of carpals)
The arm is made up of which of the following bones?
Radius Ulna Humerus
The carpal bones articulate with the:
Radius and metacarpals
How is the hand positioned for the PA Oblique projection of the hand?
Rotate the hand 450 laterally from pronated position keeping the fingers extended and parallel to the IR. (unless patient is unable and it is for a metacarpal injury)
The head of the radius fits into a depression on the lateral aspect of the coronoid process of the ulna. This depression is called the:
radial notch of the Ulna
For a lateral projection of the hand, the CR is directed to the:
second digit metacarpophalangeal joint
For the AP projection of the elbow, the hand is:
supinated
Which fat pad lies parallel with the anterior aspect of the proximal radius?
supinator
The carpometacarpal joints (2nd-5th) are of what type?
synovial gliding joints
The carpometacarpal joint between the trapezium and the 1st metacarpal is of what type
synovial saddle joint (only in the body)
what makes up the palm of the hand
the 5 anteriorly concaved metacarpals
The PA oblique projection of the wrist in lateral rotation requires a wrist angulation of:
45 degrees
Long & Rafort and Lewis describe 2 modifications of the thumb what are they and what do they demonstrate
-Long & Rafort: CR angle of 15 degrees proximally to the AP thumb -Lewis: angle 10-150 proximally to the MCP joint of the AP thumb -Demonstrates arthritic changes, fractures and displacement of the first CMC or a Bennett's Fracture -Angling can --Project soft tissue of hand away --Can open the joint space
What is the anatomical snuffbox?
-Triangular depression on the posterior surface of wrist -Visible when thumb is extended and abducted. -It is formed by the tendons of muscles of the thumb
How should the arm be positioned for the lateral projection of the humerus?
-Unless contraindicated (possible fx) internally rotate arm and flex elbow 90degrees & place palm of hand on the hip for lateromedial projection -Patient in PA with arm moved posteriorly away from the thorax for mediolateral projection -Humeral epicondyles should be perpendicular to the IR
For the PA projection of the wrist in ulnar deviation, the CR is angled:
0 degrees: according to Merrill's no angle for PA projection ulnar deviation is required (you can angle 10-15 if necessary to separate the scaphoid)
The CR angulation for the PA axial projection of the wrist (Stecher method) is:
0 degrees: wrist is elevated 20 degrees off of the IR
How far above the humeral head should the upper margin of the IR be placed for an AP humerus?
1 ½"
For the AP projection of the thumb, Lewis suggests angling the CR toward the wrist to demonstrate the first metacarpal free of the sesamoids and of the soft tissue of the palm. What is the suggested CR angle?
10º-15º
For the AP projection of the thumb, Lewis suggests angling the CR toward the wrist to demonstrate the first metacarpal free of the sesamoids and of the soft tissue of the palm. What is the suggested CR angle?
10-15 degrees
How many phalanges are in the thumb
2 (proximal and distal)
If a patient is unable to extend the elbow for the AP projection what procedure can be done in its place?
2 images in partial flexion One with the humerus parallel to IR One with the forearm parallel to the IR
The IR must be elevated how many degrees for the PA axial projection of the wrist (Stecher method)?
20 degrees: an alternative method of flat IR with 20 degree angle to the elbow of the CR will also work as the Stecher method
The CR angulation for the tangential projection (inferosuperior) of demonstrating the carpal canal is:
25-30 degrees Gaynor-Hart Method
If a patient is unable to extend the forearm for an AP projection of the elbow, how many projections are necessary to avoid distortion of the joint?
2: partial flexion
For exact positioning of the PA oblique wrist, and to ensure duplication in follow-up examinations what should be used for positioning?
45 degree foam wedge sponge
From the pronated position the wrist is rotated how much for the PA Oblique projection of the wrist?
45 degrees
How many degrees is the hand rotated for a PA oblique projection of the digit?
45 degrees
How many degrees should the elbow be angled for an AP oblique projection in medial rotation?
45 degrees
how many metacarpals are in the hand
5
how many carpals are in the wrist
8
For a lateral projection of the wrist, the elbow must be flexed:
90 degrees
For the lateral projection of the forearm, the elbow should be flexed:
90 degrees with humerus and forearm parallel to the IR and wrist in true lateral
How is the wrist and hand positioned for the PA projection of the Wrist?
Anterior surface of the forearm on the IR with the wrist to its center and the fingers slightly flexed to place the wrist joint closer to the IR. The forearm, arm and axilla should be in contact with the table.
Which of the projections of the elbow will demonstrate the radial head and neck free of superimposition?
AP Oblique Projection; external rotation
Which carpals are demonstrated in the AP Projection medial oblique of the wrist?
AP oblique projection with 450 medial rotation will demonstrate the Pisiform triquetrum and the hamate
What are the routine projections for the 1st digit? (Thumb)
AP, PA oblique, Lateral
Which projection of the wrist would be used to better demonstrate the carpal interspaces?
AP, due to the oblique situation of the carpals and the divergence of the x-rays
For the AP projection of the humerus, how should the arm be positioned?
Abduct the arm slightly and supinate the hand A coronal plane passing through the epicondyles should be parallel to the plane of IR
Which fat pads are seen on a negative lateral elbow radiograph?
Anterior and Supinator
What does the lateral projection of the wrist demonstrate?
Anterior or posterior displacement in fractures
When doing the acute flexion (Jones method) of the elbow for the proximal forearm how is the central ray directed?
CR angled to be perpendicular to the forearm entering @ 2" distal to the olecranon process The long axis of the superimposed forearm and arm should be parallel with the long axis of the IR (CR is perpendicular to humerus for distal humerus
What is the proper central ray location for the lateral projection of the hand?
CR enters the 2nd MCP joint perpendicular to the IR
How is the CR directed for the PA Projection ulnar deviation for the scaphoid?
CR is perpendicular to Scaphoid Clear delineation sometimes requires an angle the CR 10-15 degrees toward the elbow
Where is the central ray located for the Norgaard method of the hands?
CR perpendicular to IR midway between the hands at the level of the MCP joints
Which carpal does the 3rd metacarpal articulate with?
Capitate (Os Magnum)
What is carpal tunnel syndrome?
Carpal Tunnel results from Compression of the median nerve inside the carpal tunnel
The tangential Projection of the wrist (Gaynor-Hart method) demonstrates what?
Carpal canal The palmar aspect of the trapezium, the tubercle of the trapezium, hamate, triquetrum and the entire pisiform
Which structure would be projected free of superimposition for an AP oblique projection of the elbow with medial rotation?
Coronoid Process (out of its fossa)
What structures are demonstrated in the AP medial oblique projection of the elbow?
Coronoid process free of superimosition of the radial head Coronoid process out of its fossa while the Olecranon is positioned in its fossa
What does the Norgaard method demonstrate?
Done to demonstrate early radiographic changes associated with Rheumatoid Arthritis Recently used to demonstrate Fx of base of the fifth metacarpal
Describe the Arm Positioning and central ray location for the Trauma lateral projection (Coyle method) to demonstrate the radial head
Elbow flexed 900 if possible in lateral position Hand pronated CR directed at a 45 degree angle toward shoulder to the radial head
Describe the Arm Positioning and central ray location for the Trauma lateral projection (Coyle method) to demonstrate the coronoid process:
Elbow flexed only 800 (900 will obscure the coronoid process). The CR is angled 450 from the shoulder toward the elbow entering the mid elbow
Which projection of the wrist corrects foreshortening of the scaphoid?
PA in Ulnar Flexion (ulnar deviation)
The most common oblique projection of the second through fifth digits is:
PA with lateral rotation
The most common oblique projection of the second through fifth digits is
PA with lateral rotation from the pronated position
What are the routine Projections for the fingers (2-5)
PA, Oblique, lateral
For a PA projection of the second through 5th digits, the CR is directed to the:
PIP joint
What is the central ray location for the finger projections (PA, Oblique and lateral)?
PIP joint (proximal interphalangeal joint of) of the affected finger
What is the proper position of the hands for the Norgaard method?
Palmar surfaces of Hands placed together and then obliqued out at 45 degrees on wedges with the fingers extended
For the AP projection of the elbow, the humeral epicondyles are:
Parallel to the IR
How should the forearm be positioned for the PA projection of the hand?
Parallel to the table & IR: in contact with the table
How should the arm be positioned to produce an adequate image of the forearm in the AP projection?
Patient seated Humerus and forearm parallel to the table Hand supinated to prevent crossing of the radius and ulna Have patient lean laterally until forearm is in a true supinated position Adjust the humeral epicondyles to be equidistant to IR to minimize rotation
How should the arm be positioned to produce an adequate image of the AP lateral (external) oblique projection?
Patient seated at end of table with entire arm extended and parallel to IR. From an AP elbow position Rotate the hand and arm externally to place the posterior elbow in a 45 degree oblique. The thumb and 2nd digit should touch the IR.
How should the elbow be positioned to produce an adequate image of the elbow in the AP medial oblique projection?
Patient seated at end of table with entire arm extended and parallel to IR. From an AP elbow position pronate the hand and adjust the anterior surface of the elbow to 450 angle
What is the central ray location for the thumb projections: AP, lateral and oblique?
Perpendicular to enter at the 1st MCP joint (metacarpophalangeal joint)
What is the Central Ray location when performing a PA Hand?
Perpendicular to the IR and Hand at the 3rd Metacarpophalangeal joint
Which carpal is the smallest?
Pisiform
What is the correct position of the arm and wrist for the lateral projection of the wrist (lateromedial)
Place entire arm and forearm with the ulnar side down on the table (parallel to table and IR) Have patient flex elbow 900 to rotate ulna into lateral position
What is the correct position for the PA ulnar deviation for the scaphoid?
Place wrist in true PA position Deviate the hand/wrist as much as possible
Flexing the fingers for a PA projection of the wrist causes:
Placement of the carpal bones closer to the IR
The bone part shown in the figure above is the:
Proximal Unla
What projections should be done to achieve the humerus in a lateral position when there is trauma involved?
Transthoracic Lateral (Lawrence method) for the proximal end and a Lateral of the distal end separately
Which of the carpals are well demonstrated on a PA oblique projection of the wrist?
Trapezium and Scaphoid: the PA external oblique demonstrates the lateral side carpals