Finger (oblique view)

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Finger oblique view is a standard projection for radiographic assessment of the fingers.

Indications

The oblique view s not required for follow-up studies, or 'query foreign body' unless specifically requested. It is, however, a very useful projection in the acute setting and should be included in the acute finger series to ensure no subtle pathology is missed .

Patient position

  • patient is seated alongside the table (similar to a projection of hand)
  • from a pronated position for PA fingers, the hand is rotated approximate 45 degrees (thumb side up), resting on a sponge if required (see Figure 1)
  • fingers are separated to avoid superimposition
  • the long axis of the finger should run parallel to the image receptor (in horizontal and vertical planes)

Technical factors

  • posteroanterior oblique projection
  • centering point
    • approximately over the proximal interphalangeal joint
  • collimation
    • laterally to the skin margins
    • proximal to include the carpometacarpal joint
    • distal to the tips of the distal phalanges 
  • orientation  
    • portrait
  • detector size
    • 18 cm x 24 cm
  • exposure
    • 50-60 kVp
    • 1-5 mAs
  • SID
    • 100 cm
  • grid
    • no

Image technical evaluation

Digit is examined to include the carpometacarpal joint. The condyles of the phalanges are oblique as seen via little superimposition of the two domes. There is a noted uneven concavity of the mid-shaft of the metacarpal. On the raised side, there is more soft tissue

Practical points

The oblique finger has a proven high diagnostic yield, patients may not be able to maintain an oblique position, you can assist them via a small 30-degree sponge.

Excessive superimposition of the of the metacarpals indicates the hand is externally elevated too much.

Separation of the metacarpals (almost a PA view) means the hand must be raised slightly.