Upper-Limb-Positioning.pdf

Upper Limb (Positioning) Joel R. Milar, RRT, MSHSMc  General Procedures Remove rings, watches, and other radiopaque objects, and place them in secure storage during the procedure. Seat the patient at the side or end of the table to avoid a strained or uncomforta...

Upper Limb (Positioning) Joel R. Milar, RRT, MSHSMc  General Procedures Remove rings, watches, and other radiopaque objects, and place them in secure storage during the procedure. Seat the patient at the side or end of the table to avoid a strained or uncomfortable position. Place the IR at a location and angle that allows the patient to be in the most comfortable position Direct the central ray at a right angle to the midpoint of the IR.  General Procedures Radiograph each side separately when performing a bilateral examination of the hands or wrists; this prevents distortion, particularly of the joint spaces Shield gonads Use close collimation Use right or left markers and any other identification markers  Digits (Second - Fifth Digits)  PA PROJECTION PP: palmar surface down, slightly EC: separated digits Entire digit from fingertip to distal RP: PIP Joint portion of the adjoining metacarpal CR: Perpendicular No soft tissue overlap from adjacent SS: PA Projection of affected digit digits Collimation: No rotation of the digit demonstrated by concavity of the 1 inch (2.5 cm) on all sides of the digit, phalangeal bodies and an equal including 1 inch (2.5 cm) proximal to the MCP joint amount of soft tissue on both sides of the phalanges Open IP and MCP joint spaces NOTE: Digits that cannot be extended can be examined in small sections. When joint injury is suspected, an AP projection instead of a PA projection is recommended.  LATERAL PROJECTION (Lateromedial or Mediolateral) PP: hand rests on lateral/radial EC: surface (2nd and 3rd digits) or Entire digit in a true lateral position medial/ulnar surface (4th or 5th Concave, anterior surfaces of the digits) phalanges RP: PIP Joint No rotation of the phalanges CR: Perpendicular No obstruction of the proximal phalanx or MCP joint SS: Lateral projection of Open IP joint spaces affected digits  PA OBLIQUE PROJECTION (Lateral Rotation) PP: Hand pronated, palmar surface down; hand externally/laterally rotated (45⁰), may use 45-degree foam wedge. RP: PIP joint CR: Perpendicular SS: PA oblique projection of the affected digit EC: Entire digit rotated 45 degrees demonstrated by the concavity of the elevated side of the phalangeal bodies No superimposition Open IP and MCP joint spaces  STREET Method Medial Rotation – rotate the second digit medially from the prone position. The advantage of medially rotating the digit is that the part is closer to the IR for improved recorded detail and increased visibility of certain fractures.  Review of Projections (2nd – 5th Digits) PA Projection Lateral Projection (Lateromedial or Mediolateral) PA Oblique Projection (Lateral Rotation) PA Oblique Projection (Medial Rotation) – Street Method  Digits (First Digit)  AP PROJECTION PP: arm is internally rotated; hand is in extreme internal/medial rotation; thumb posterior surface down. RP: 1st MCP Joint CR: Perpendicular SS: AP Projection of the thumb EC: Entire digit with trapezium in profile No rotation (concave phalangeal and metacarpal bodies) Overlap of soft tissue profile (palm and 1st metacarpal) Open IP and MCP Joint spaces AP PROJECTION  LEWIS Modification CR: 10-15 Degrees along the long axis of the thumb toward the wrist. Rationale: To show the first metacarpal free of soft tissue of the palm  PA PROJECTION PP: EC: Hand resting on its medial surface Entire digit with trapezium in PA projection of 1st CMC and 1st Digit - profile hand in lateral position and dorsal surface of the thumb parallel with the IR No rotation (concave RP: 1st MCP Joint phalangeal and metacarpal bodies) CR: Perpendicular Overlap of soft tissue profile SS: Magnified PA Projection of (palm and 1st metacarpal) the thumb Open IP and MCP Joint spaces PA PROJECTION  LATERAL PROJECTION PP: EC: Hand is relaxed and in its Entire digit with trapezium in natural arched position, palmar profile surface down No Rotation: Concave, anterior RP: 1st MCP Joint surface of the proximal phalanx CR: Perpendicular Overlap of soft tissue profile SS: Lateral Projection of the (palm and 1st metacarpal) thumb Open IP and MCP Joint spaces LATERAL PROJECTION  PA OBLIQUE PROJECTION PP: Palmar surface on the IR; EC: Thumb is abducted; Hand in Entire digit with trapezium in slightl ulnar deviation profile RP: 1st MCP Joint Proper Rotation: Concave, CR: Perpendicular anterior surface of the elevated SS: PA Oblique Projection of the side of the proximal phalanx thumb Open IP and MCP Joint spaces  Review of Projections (1st Digit) AP Projection PA Projection Lateral Projection PA Oblique Projection First Carpometacarpal Joint  AP PROJECTION (Robert Method) PP: shoulder, elbow, and wrist on the EC: same plane to prevent elevation of the First CMC joint free of carpal bones and closing of the 1st superimposition. CMC Joint. Extend the limb straight out on the radiographic table. Arm is 1st Metacarpal with the base in internally rotated. Hand is convex profile hyperextended so that the soft tissue Trapezium over the ulnar aspect does not obscure the 1st CMC Joint RP: 1st CMC Joint Exam Rationale: CR: Perpendicular To demonstrate arthritic changes, fractures, displacement of the first SS: first CMC joint free of CMC joint and Bennet fracture superimposition  AP PROJECTION (Long and Rafert Modification) PP: shoulder, elbow, and wrist on the SS: first CMC joint free of same plane to prevent elevation of the superimposition carpal bones and closing of the 1st CMC EC: Joint. Extend the limb straight out on the radiographic table. Arm is internally First CMC joint free of rotated. Hand is hyperextended so that superimposition. the soft tissue over the ulnar aspect does 1st Metacarpal with the base in not obscure the 1st CMC Joint. Patient convex profile may hold the fingers back with the other hand. Trapezium RP: 1st CMC Joint CR: 15 proximally along the long axis of the thumb entering 1st CMC joint. Collimation includes the entire thumb  AP PROJECTION (Lewis Modification) PP: shoulder, elbow, and wrist on the EC: same plane to prevent elevation of the First CMC joint free of carpal bones and closing of the 1st CMC superimposition. Joint. Extend the limb straight out on the radiographic table. Arm is internally 1st Metacarpal with the base in rotated. Hand is hyperextended so that convex profile the soft tissue over the ulnar aspect does Trapezium not obscure the 1st CMC Joint. RP: 1st MCP Joint CR: 10 -15 proximally along the long axis of the thumb entering 1st MCP joint. SS: first CMC joint free of superimposition A - Optimal radiograph of AP first CMC joint (arrow): Robert method. B - Example of typical repeat radiograph. Soft tissue of palm (arrows) obscured first CMC joint. Long-Rafert or Lewis modification of central ray would help show the joint on this patient  Angulation Rationale (Long-Rafert and Lewis Modification) Angulation of the central ray serves two purposes: (1) It may help project the soft tissue of the hand away from the first CMC joint (2) It can help open the joint space when the space is not shown with a perpendicular central ray.  AP PROJECTION (Burman Method) When hyperextension of the wrist is not contraindicated, Burman stated that this projection provides a clearer image of the first CMC joint than is seen on the standard AP projection SID: 18 inches; this produces a magnified image that creates a greater field of view of the concavo-convex aspect of this joint.  AP PROJECTION (Burman Method) PP: forearm approximately parallel with adjacent carpals. the long axis of the IR; Hand 1st Metacarpal with the base in hyperextended and the position is held by convex profile the other hand or with a bandage looped around the digits. Hand is rotated Trapezium in concave profile internally. Thumb is abducted and flat on the IR RP: 1st CMC Joint CR: 45 toward the elbow. SS: magnified concavo-convex outline of the first CMC joint EC: First CMC joint, unobscured by  Review of Projections (1st CMC Joint) AP Projection (Robert Method) Long-Rafert modification Lewis Modification AP Projection (Burman Method) First Metacarpophalangeal Joint  PA PROJECTION (Folio Method) This projection is useful for the diagnosis of ulnar collateral ligament (UCL) rupture in the MCP joint of the thumb, also known as “skier’s thumb.” NOTE: To avoid motion, have the correct technical factors set on the generator and be ready to make the exposure before instructing the patient to pull the thumbs apart.  PA PROJECTION (Folio Method) PP: Hands on the cassette, resting EC: them on their medial aspects. Wrap Thumb in PA projection. a rubber band around the distal portion of both thumbs and place a 1st Metacarpals with MCP joints roll of medical tape between the bodies of the first metacarpals. Thumbnails parallel to the cassette. RP: midway both hands at the level of MCP Joints CR: Perpendicular. SS: MCP joints and MCP angles bilaterally Hand  PA PROJECTION PP: hand with the palmar surface down EC: on the IR. Fingers slightly spread Entire hand including the distal RP: 3rd MCP Joint radius and ulna CR: Perpendicular No soft tissue overlap SS: PA Projection of carpals, metacarpals, No rotation of the hand phalanges (except the thumb), demonstrated by equal concavity of interarticulations of the hand, and distal the metacarpal and phalangeal bodies radius and ulna are shown, PA oblique on both sides of the phalanges projection of the first digit. Open IP and MCP joint spaces, indicating the hand is placed flat on the IR NOTE: When the MCP joints are under examination and the patient cannot extend the hand enough to place its palmar surface in contact with the IR, the position of the hand can be reversed for an AP projection. This position is also used for the metacarpals when the hand cannot be extended because of an injury, a pathologic condition, or the use of dressings. SPECIAL TECHNIQUES: Clements and Nakayama described a special exposure technique for imaging early rheumatoid arthritis. Lewis described a positioning variation to place the second through fifth metacarpals parallel to the IR, resulting in a true PA projection.  PA OBLIQUE PROJECTION (Lateral Rotation) This supplemental position is used for SS: PA Oblique Projection of the hand investigating fractures and pathologic EC: conditions. Entire hand including the distal PP: radius and ulna Palmar surface down, MCP joints is Digits separated slightly with no approx. 45 degrees with the IR (may overlap use foam wedge) – LATERALLY ROTATED 45 rotation of the anatomy. (minimal overlap of 3rd, 4th and 5th Metacarpals – fingertips touch the IR metacarpal base and head, separation RP: 3rd MCP Joint of 2nd and 3rd metacarpal) CR: Perpendicular Open IP and MCP joint spaces  REVERSE OBLIQUE PROJECTION (Lane-Kennedy-Kuschner Recommendation) For better demonstration of severe metacarpal deformities or fractures PP: Palmar surface down, MCP joints is approx. 45 degrees with the IR, MEDIALLY ROTATED RP: 3rd MCP Joint CR: Perpendicular SS: PA Oblique Projection of the hand  REVERSE OBLIQUE PROJECTION (Lane-Kennedy-Kuschner Recommendation) EC: Entire hand including the distal radius and ulna Digits separated slightly with no overlap 45 rotation of the anatomy. (minimal overlap of 3rd, 4th and 5th metacarpal base and head, separation of 2nd and 3rd metacarpal) Open IP and MCP joint spaces  TANGENTIAL OBLIQUE PROJECTION (Kallen Recommendation) For demonstration of metacarpal head fracture PP: Palmar surface down, Hand is rotated 40-45 degrees toward the ulnar surface and 40-45 degrees forward; MCP Joints are flexed 75-80 degrees. Hand dorsum resting on the IR RP: MCP Joint of interest CR: Perpendicular SS: PA Oblique Projection of the hand  TANGENTIAL OBLIQUE PROJECTION (Kallen Recommendation) EC: Entire hand including the distal radius and ulna Digits separated slightly with no overlap 45 rotation of the anatomy. (minimal overlap of 3rd, 4th and 5th metacarpal base and head, separation of 2nd and 3rd metacarpal) Open IP and MCP joint spaces  LATERAL PROJECTION (Mediolateral/Lateromedial Extension and Fan Lateral) Customary position for localizing foreign bodies and metacarpal fracture displacement. PP: Hand in lateral position; digits extended; thumb is abducted and is 90 to the palm LATEROMEDIAL (ulnar aspect down) MEDIOLATERAL (radial aspect down) – more difficult to do FAN LATERAL – digits on a sponge wedge  LATERAL PROJECTION (Mediolateral/Lateromedial Extension and Fan Lateral) RP: 2nd MCP Joint CR: Perpendicular SS: Lateral projection of the hand in extension. The fan lateral superimposes the metacarpals but shows almost all of the individual phalanges. EC: Entire digits to distal radius and ulna Extended digits True lateral (superimposed metacarpals, distal radius and ulna)  LATERAL PROJECTION (Lewis Recommendation) Rationale: For better demonstration of the fifth metacarpal fractures PP: Hand is rotated 5° posteriorly from true lateral position to remove superimposition of 2nd to 4th metacarpals; Thumb extended RP: Midshaft of 5th metacarpal CR: Parallel to the extended thumb  LATERAL PROJECTION (Lateromedial in Flexion) This projection is useful when a hand injury prevents the patient from extending the fingers. It also shows anterior or posterior displacement in fractures of the metacarpals. PP: Forearm rested on the table; Hand’s ulnar aspect down; Digits are relaxed maintaining natural arch and perfectly superimposed with each other RP: 2nd MCP Joint CR: Perpendicular SS: Lateral Projection of the hand in their normally flexed position  LATERAL PROJECTION (Lateromedial in Flexion) EC: entire digits with distal radius and ulna Flexed digits Superimposed phalanges and metacarpals Superimposed distal radius and ulna Thumb free of superimposition  AP OBLIQUE PROJECTION – Medial Rotation (Norgaard Method) Aka ball-catcher’s position. Assists in detecting early radiologic changes in the dorsoradial aspects of the 2nd – 5th proximal phalangeal bases that may be associated with rheumatoid arthritis. Norgaard reported that it is often possible to make an early diagnosis of rheumatoid arthritis by using this position before laboratory tests are positive. FILM-SCREEN – low kVp (60 to 65 kVp) to obtain optimum resolution and contrast. Stapczynski recommended this projection to show fractures of the base of the fifth metacarpal.  AP OBLIQUE PROJECTION – Medial Rotation (Norgaard Method) PP: Both hands in half-supinated position with medial aspect against the IR; dorsal surface of each hand rests against each 45-degree sponge support. Fingers extended; Thumb slightly abducted to avoid superimposing them over the second MCP joint.. MODIFIED POSITION: Fingers are not extended (cupped as though the patient is going to catch a ball) RP: Point midway between both hands at the level of the MCP joints CR: Perpendicular SS: AP 45- degree oblique projection of both hands  AP OBLIQUE PROJECTION – Medial Rotation (Norgaard Method) EC: Both hands from the carpal area to the tips of the digits Metacarpal heads and proximal phalangeal bases free of superimposition The early radiologic change significant in making the diagnosis of rheumatoid arthritis is a symmetric, very slight, indistinct outline of the bone corresponding to the insertion of the joint capsule dorsoradial on the proximal end of the first phalanx of the four fingers. In addition, associated demineralization of the bone structure is always present in the area directly below the contour defect.  Review of Projections (Hand) PA Projection PA Oblique Projection (Lateral Rotation) Reverse Oblique Projection (Lane-Kennedy-Kushner Recommendation) Tangential Projection (Kallen Recommendation) Lateral Projection (Mediolateral/Lateromedial Extension and Fan Lateral) Lewis Recommendation Lateral Projection (Lateromedial in Flexion) AP Oblique Projection – Medial Rotation (Norgaard Method)