Finger - Oblique

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Radiographic Positioning


Adult
Other related pages of interest

Name of projection Finger - Oblique
Area Covered Phalanges of affected digit and distal half of adjoining metacarpal
Pathology shown Fracture, dislocation, foreign body, infection, tumour, arthritis
Radiographic Anatomy Hand Radiographic Anatomy
IR Size & Orientation 18 x 24cm
Landscape, divided for multiple finger images, use lead masking for unused area
Film / Screen Combination Detail
(CR and DR as recommended by manufacturer)
Bucky / Grid No
Filter No
Exposure 50 kVp
2 mAs
FFD / SID 100cm
Central Ray Directed to the proximal interphalangeal joint of affected digit
Perpendicular to the IR
Collimation Centre: Proximal interphalangeal joint
Shutter A: To include distal phalanx to half the adjoining metacarpal
Shutter B: To include soft tissue
Markers Distal and Lateral
Marker orientation AP
Shielding Gonadal (check your department's policy guidelines)
Respiration Not applicable
Positioning
  • Seat patient at end of table
  • Forearm on table
  • Hand pronated
  • Rotate hand 45° laterally
  • For 2nd digit can rotate medially to bring digit closer to IR
  • Support with sponge
  • Separate digits
  • Digit of interest parallel to IR to open interphalangeal joint
Critique

Positioning
  • Entire digit at a 45° angle, including the distal portion of the adjoining metacarpal, shown by
    • There is twice as much soft tissue width on the raised side
    • There is greater concavity on the mid-shaft of the phalanx on the raised side
  • No soft tissue overlap from adjacent digits
  • No super-imposition of the proximal phalanx and the metacarpophalangeal joint
  • Metacarpophalangeal joint space and interphalngeal joint spaces are open
  • Long axis of digit is aligned with the long axis of the IR
  • Phalanges are not foreshortened
Area Covered
  • Distal, middle and proximal phalanges and half the adjoining metacarpal
Collimation
  • From the distal phalanx to half the adjoining metacarpal and the soft tissues
Exposure
  • Bony trabecular patterns and cortical margins are sharply defined
  • Soft tissues are visualised
Special Notes