Forearm (lateral view)

Radiopaedia • CC-by-nc-sa 3.0 • de

Forearm lateral view is one of two standard projections in the forearm series to assess the radius and ulna.

Indications

This view allows for the assessment of suspected dislocations or fractures and localizing foreign bodies within the forearm.

Patient position

  • patient is seated alongside the table
  • elbow is flexed to 90 degrees and the medial aspect of the wrist, forearm and elbow joint are placed in contact with the detector
  • shoulder, elbow and wrist should be in the same horizontal plane

Technical factors

  • lateral projection
  • centering point
    • mid forearm region
  • collimation
    • distal to the wrist joint 
    • proximal to elbow joint
  • orientation  
    • portrait
  • detector size
    • 24 cm x 30 cm
  • exposure
    • 50-60 kVp
    • 3-5 mAs
  • SID
    • 100 cm
  • grid
    • no

Image technical evaluation

  • elbow is in a lateral position, as confirmation by the trochlea and capitulum being superimposed and the radial head being seen in profile.
  • there should be superimposition of the distal radius and ulna indicating a lateral position 

Practical points

Contrary to popular belief the lateral forearm should not be considered a view to evaluating any occult injuries of the wrist joint and or elbow due to beam divergence. Beam divergence at the edges of the image should be acknowledged when assessing anatomy (see Figure 1) .