Positioning for Chapter 4
Exception: PA ( only if patient cannot position AP)
Place hand in near-lateral position and rest thumb on sponge support block that is high enough so that the thumb is not rotated but is in position for a true PA projection
Exception to PA oblique hand
for a routine oblique hand, use a support block to place digits parallel to IR. This block prevents foreshortening of phalanges and obscuring of interphalangeal joints. If the metacarpals only are of interest, the image an be taken with thumb and finger tips touching IR
AP oblique bilateral projection: hand norgaard method
seat patient at end of table with both hands extended supinate hands and place medial aspect of both hands together at center of IR - from this position, internally rotate hands 45 degrees and support posterior aspect of hands on 45 degrees radiolucent blocks -extend fingers and ensure that they are relaxed, slightly separated but parallel to IR -abduct both thumbs to avoid superimposition
PA stress thumb projection-- folio method
seat patient at end of table with both hands extended and pronated on IR -position both hands side by side to center of IR, rotated laterally into 45 degrees oblique position, resulting in PA projection of both thumbs - place supports as needed under both wrist and proximal thumb regions to prevent motion. ensure that hands are rotated enough to place thumbs parallel to IR ( cassette) for PA projection of both thumbs - place round spacer, such as a roll of medical tape, between proximal thumb regions; wrap rubber bands around distal thumb as shown -immediately before exposure, ask patient to pull thumbs apart firmly and hold
"Fan" lateral-lateromedial projection: hand
seat patient at end of table with hand and forearm extended -align long axis of hand with long axis of IR - rotate hand and wrist into lateral position with thumb side up. -spread fingers and thumb into a " fan" position, and support each digit on radiolucent block as shown. Ensure that all digits, including the thumb, are separated and parallel to IR and that the metacarpals are not rotated but remain in a true lateral position
PA projection: Hand
seat patient at end of table with hand and forearm extended - pronate hand with palmar surface in contact with IR; spread fingers slightly - align long axis of hand and forearm with long axis of IR - center hand and wrist to IR
PA oblique projection; Hand
seat patient at end of table with hand and forearm extended -pronate hand on IR; center and align long axis of hand with long axis of IR - rotate entire hand and wrist laterally 45 degrees and support with radiolucent wedge or step block, as shown, so that all digits are separated ad parallel to IR
Lateral in extension and flexion- lateromedial projections: Hand Alternatives to fan lateral
seat patient at end of table with hand and forearm extended rotate hand and wrist, with thumb, side up, into true lateral position, with second to fifth MCP joints centered to IR and CR - lateral in extension: Extend fingers and thumb, and support against a radiolucent support block. Ensure that all fingers and metacarpals are superimposed directly for true lateral position -lateral in flexion: flex fingers into a natural flexed position, with thumb lightly touching the first finger; maintain true lateral position
PA (AP) projection: wrist
seat patient at end of table with hand and forearm extended. Drop shoulder so that shoulder, elbow, and wrist are on same horizontal plane - align and center long axis of hand and wrist to IR, with carpal area centered to CR - with hand pronated, arch hand slightly to place wrist and carpal area in close contact with IR
Pa scaphoid- hand elevated and ulnar deviation: wrist modified stecher method
seat patient at end of table with hand and forearm extended. Drop shoulder so that shoulder, elbow, and wrist are on same horizontal plane - place hand and wrist palm down on IR with hand elevated on 20 degree angle sponge -ensure that wrist is in direct contact with IR - gently evert or turn hand outward ( toward ulnar side) unless contraindicated because of severe injury alternative: have patient clench the fist with ulnar deviation to obtain a similar position of the scaphoid
PA projection- radial deviation: wrist
seat patient at end of table with hand and forearm extended. Drop shoulder so that shoulder, elbow, and wrist are on same horizontal plane - position wrist as for PA projection-palm down with wrist and hand aligned with center of long axis of IR - without moving forearm, gently invert the hand ( move medially toward thumb side) as far as patient can tolerate without lifting or rotating distal forearm
PA oblique projection--lateral rotation: wrist
seat patient at end of table with hand and forearm extended. Drop shoulder so that shoulder, elbow, and wrist are on same horizontal plane -align and center hand and wrist to IR -from pronated position, rotate wrist and hand laterally 45 degrees - for stability, place a 45 degree support under thumb side of hand o support hand and wrist in a 45 oblique position or partially flex fingers to arch hand so that fingertips rest lightly on IR without support
Lateromedial projection: wrist
seat patient at end of table with hand and forearm extended. Drop shoulder so that shoulder, elbow, and wrist are on same horizontal plane -align and center hand and wrist to long axis of IR -adjust hand and wrist into a true lateral position, with fingers comfortable extended; if support is needed to prevent motion, use a radiolucent support block and sandbag, and place block against hand and fingers
Acute flexion projections: elbow
seat patient at end of table, with acutely flexed arm resting on IR - align and center humerus to long axis of IR, with forearm acutely flexed and fingertips resting on shoulder -adjust IR to center of elbow joint region -palpate humeral epicondyles and ensure interepicondylar place is parallel to IR for no rotation
Radial Head- lateromedial projections: elbow
seat patient at end of table, with arm flexed 90 degrees and resting on IR with humerus, forearm, and hand on same horizontal plane. - center radial head area to center of IR, positioned so that distal humerus and proximal forearm are placed "square" with or parallel with the borders of IR - center radial head region to CR - take four projections, the only difference among the four being rotation of the hand and wrist from 1) maximum external rotation to 4) maximum internal rotation; different parts of the radial head projected clear of the coronoid process are demonstrated. Near complete rotation of radial head occurs
AP oblique projection- medial ( internal) rotation : elbow
seat patient at end of table, with arm fully extended and shoulder and elbow on same horizontal plane - align arm and forearm with long axis of IR. Center elbow joint to CR and to IR - pronate hand into a natural palm-down position and rotate arm as needed until distal humerus and anterior surface of elbow are rotated 45 degrees
AP oblique projection-Lateral ( external ) rotation: Elbow
seat patient at end of table, with arm fully extended and shoulder and elbow on same horizontal plane ( lowering shoulder as needed) - align arm and forearm with long axis of Ir -center elbow joint to CR and to IR - supinate hand and rotate laterally the entire arm so that the distal humerus and the anterior surface of the elbow joint are approximately 45 degrees to IR ( patient must lean laterally for sufficient lateral rotation).Place interepicondylar place approximately 45 degrees to the IR
Lateromedial projection: elbow
seat patient at end of table, with elbow flexed 90 degrees - align long axis - center elbow joint to CR and to IR - drop shoulder so that humerus and forearm are on same horizontal plane - rotate hand and wrist into true lateral position, thumb side up. Place interepicondylar plane perpendicular to IR -place support under hand and wrist to elevate hand and distal forearm as needed for heavy muscular forearm so that forearm is parallel to IR for true lateral elbow
Lateromedial projection: forearm
seat patient at end of table, with elbow flexed 90 degrees - drop shoulder to place entire upper limb on same horizontal place -align and center forearm to long axis of IR; ensure that both wrist and elbow joints are included on IR - rotate hand and wrist into true lateral position, and support hand to prevent motion, if needed ( ensure that distal radius and ulna are superimposed directly) -for heavy muscular forearms, place support under hand and wrist as needed to place radius and ulna parallel to IR
AP projection: elbow elbow fully extended
seat patient at end of table, with elbow fully extended - extend elbow, supinate hand, and align arm and forearm with long axis of IR - center elbow joint to center of IR - ask patient to lean laterally as necessary for true AP projection. Palpate humeral epicondyles to ensure that interepicondylar plane is parallel to IR support hand as needed to prevent motion
AP projection- alternative partial flexion: elbow
seat patient at end of table, with elbow partially flexed - obtain two AP projections- one with forearm parallel to IR and one with humerus parallel to IR - place support under wrist and forearm for projection with humerus parallel to IR, if needed, to prevent motion
Lateral position: thumb
seat patient at end of table, with elbow, flexed about 90 degrees with hand resting on IR, palm down -start with hand pronated and thumb abducted, with fingers and hand slightly arched; then rotate hand slightly medial until thumb is in true lateral position ( you may need to provide a sponge or other support under lateral portion of hand ) - align long axis of thumb with long axis of the IR -center first MCP joint to CR and to center of IR - entire lateral aspect of thumb should be in direct contact with IR
AP projection: Forearm
seat patient at end of table, with hand and arm fully extended and palm up ( supinated) - drop shoulder to place entire upper limb on same horizontal plane -align and center forearm to long axis of IR, ensuring that both wrist and elbow joints are included - instruct patient to lean laterally as necessary to place entire wrist, forearm, and elbow in as near a true frontal position as possible. Palpate the medial and lateral epicondyles to ensure they are the same distance from IR
Carpal canal ( tunnel) tangential, inferosuperior projection: wrist gaynor-hart method
seat patient at end of table, with wrist and hand on IR and palm down ( pronated) -align hand and wrist with long axis of the IR - ask patient to hyperextend wrist (dorsiflex) as far as possible by the use of a piece of tape or band and gently but firmly hyperextending the wrist until the long axis of the metacarpals and the fingers are as near vertical as possible ( without lifting the wrist and forearm from the IR) - rotate entire hand and wrist about 10 degrees internally ( toward radial side) to prevent superimposition of pisiform and hamate
PA and PA axial scaphoid- with ulnar deviation: wrist
seat patient at end of table, with wrist and hand on IR, palm down., and shoulder, elbow, and wrist on same horizontal plane - position wrist as for PA projection--palm down and hand on wrist aligned with center of long axis of IR, with scaphoid centered to CR -without moving forearm, gently evert hand ( move toward ulnar side) as far as patient can tolerate without lifting or rotating distal forearm
PA projection: fingers
seat patient at end of the table, with elbow flexed about 90 degrees and with hand and forearm resting on table -Pronate hand with fingers extending -center and align long axis of affected finger with long axis of IR -separate adjoining fingers from affected finger
PA oblique projection-medial rotation: thumb
seat patient at the end of table with hand resting on IR - abduct thumb slightly with palmar surface of hand in contact with IR ( this action naturally places thumb in a 45 degree oblique position) - align long axis of thumb with long axis of IR - Center first MCP joint to CR and to center of IR
PA oblique projection- medial or lateral rotation: Fingers
seat patient at the end of table, with elbow flexed about 90 degrees with hand and wrist resting on IR and fingers extended - with fingers extending against 45 degree foam wedge block, place hand in a 45 degree lateral oblique ( thumb side up) - position hand on IR so that the ling axis of the finger is aligned with long axis of IR - separate fingers and carefully place finger that is being examined against block, so it is supported in a 45 degree oblique and parallel to IR
Lateromedial or mediolateral projections: fingers
seat patient at the end of table, with elbow flexed about 90 degrees with hand and wrist resting on IR and fingers extended -place hand in lateral position ( thumb side up ) with finger to be examined fully extended ad centered to portion of IR being exposed - align and center finger to long axis of IR and to CR -use sponge block or other radiolucent device to support finger and prevent motion. Flex unaffected fingers -ensure that long axis of finger is parallel to IR
Trauma axial lateromedial and mediolateral projection: elbow coyle method
seat patient at the end of the table for the erect position or supine on table for cross-table imaging Position 1: radial head-axial lateromedial projection - elbow flexed 90 degrees Position 2: coronoid process- axial mediolateral projection - elbow flexed only 80 degrees from extended position and hand is pronated
AP projection: thumb
seat patient facing table, arms extending in front, with hand rotated internally to supinate thumb for AP projection First, demonstrate for patient -internally rotate hand with fingers extended until posterior surface of thumb is in contact with IR. Immobilize other fingers with tape to isolate thumb if necessary -align thumb with long axis of the IR -center first MCP joint to CR and to center of IR. immobilize other fingers with tape to isolate thumb if necessary
AP axial projection ( modified robert's method): thumb
seat patient parallel to end of table, with hand and arm fully extended -rotate arm internally until posterior aspect of thumb rests on IR -place thumb in center of IR, parallel to side border of IR -entend fingers
Optional medial oblique for fingers
second digit also may be taken in a 45 degree medial oblique ( thumb side down) with thumb and other fingers flexed to prevent superimposition. This position places the part closer to the IR for improved definition but may be more painful for the patient. Lateral rotation of hand is recommended to demonstrate the 3rd, 4th, and 5th digit
Carpal bridge-tangential projection: wrist
Have patient stand or sit at end of the table and then lean over and place dorsal surface of hand, palm upward, on IR - center dorsal aspect of carpals to IR -gently flex wrist as far as patient can tolerate or until the hand and forearm form as near a 90 degree angle as possible
What are the four projections?
1. supinate hand ( palm up ) and externally rotate as far as patient can tolerate 2. place hand in true lateral position ( thumb up) 3. pronate hand ( palm down) 4. internally rotate hand ( thumb down) as far as patient can tolerate
Alternative imaging for carpal canal
sonography: high resolution ultrasonography allows for noninvasive imaging of the carpal tunnel and related anatomy.