Hand (ball-catcher view)

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The ball-catcher view, Nørgaard projection, or posterior oblique view of both hands is an additional projection of the routine hand series.

Indications

The ball-catcher view is typically undertaken to assess for erosive arthropathies such as rheumatoid arthritis. It often complements the bilateral PA view of the hands and is generally thought to be the superior view to illustrate joint erosions.

Patient position

  • the patient may be seated alongside or facing the table
  • both hands are supinated with their dorsal surfaces are placed on the cassette/FPDs
  • the hands are then rotated medially by 45 degrees to assume a position likened to one about to receive or catch a ball 

Technical factors

  • anterior bilateral projection
  • centering point
    • between the two hands at the level of the metacarpophalangeal joints 
  • collimation
    • laterally to the skin margins
    • distal to the skin margins of the fingertips
    • proximal to the include one-third of the distal radius and ulna
  • orientation  
    • landscape
  • detector size
    • 24 cm x 30 cm
  • exposure
    • 50-60 kVp
    • 3-5 mAs
  • SID
    • 100 cm
  • grid
    • no

Image technical evaluation

  • no overlap of the midshafts of the metacarpals, nor is there an overlap of the phalange bases
  • hands are equal distance apart

Practical points

If the metacarpal shafts are overlapping, the hands are over obliqued and the angle needs to be more shallow - it is best to use two 45 degree sponges to help, rest the posterior aspects of the hands on the sponges so they resemble 'catching hands'.