Thumb - LateralThis is a featured page

Radiographic Positioning


Adult
Other related pages of interest

Name of projection Thumb - Lateral
Area Covered Distal and proximal first phalanx, metacapal, carpometacarpal joint, trapezium
Pathology shown Fracture, dislocation, foreign body, infection, tumour, arthritis
Radiographic Anatomy Hand Radiographic Anatomy
IR Size & Orientation 18 x 24cm
Landscape, divided for multiple thumb 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
2.5 mAs
FFD / SID 100cm
Central Ray Directed to first metacarpophalangeal joint
Perpendicular to IR
Collimation Centre: First metacarpophalangeal joint
Shutter A: From distal phalanx to trapezium
Shutter B: To include soft tissues
Markers Distal and Lateral
Marker orientation AP
Shielding Gonadal (check your department's policy guidelines)
Respiration Not applicable
Positioning
  • Seated at end of table
  • Palmar surface of hand down
  • Flex hand slightly until thumb is in lateral position
  • Thumb against IR
  • Long axis of thumb in line with axis of IR
  • Centre to metacarpophalangeal joint
Critique

Positioning
  • First digit in true lateral position is demonstrated by
    • anterior surface of proximal phalanx is concave
    • posterior surface of proximal phalanx and metacarpal will be slightly convex
    • Thumbnail, if visualised, will be in profile
    • Proximal first metacapal slightly super-imposed by proximal second metacarpal
  • The following joint spaces are open: metacarpophalangeal, interphalangeal, carpometacarpal
  • Long axis of digit is aligned with long axis of IR
  • Centred to metacarpophalangeal joint
Area Covered
  • Distal and proximal first phalanx, metacapal, carpometacarpal joint, trapezium
Collimation
  • Centred to first metacarpophalangeal joint
  • Opened to include distal phalanx to trapezium and soft tissues
Exposure
  • Bony trabecular patterns and cortical outlines are sharply defined
  • Soft tissues are visualised
Special Notes



AndyC
AndyC
Latest page update: made by AndyC , Jun 17 2011, 2:25 PM EDT (about this update About This Update AndyC Edited by AndyC

1 word added
1 word deleted

view changes

- complete history)
More Info: links to this page
There are no threads for this page.  Be the first to start a new thread.

Related Content

  (what's this?Related ContentThanks to keyword tags, links to related pages and threads are added to the bottom of your pages. Up to 15 links are shown, determined by matching tags and by how recently the content was updated; keeping the most current at the top. Share your feedback on Wetpaint Central.)