Tibia fibula (AP view)

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The tibia fibula anteroposterior view is part of a two view series of the entire tibia, fibula, and both the knee and ankle joint.

Indications

The tibia fibula AP view is performed for evaluation of the lower leg in patients who have suffered trauma or are suspected to have a foreign body or bone lesion including osteomyelitis. If one is concerned about the ankle joint, the ankle series is more appropriate, if the knee is the point of focus, a knee series.

Patient position

  • the patient may be supine or sitting upright with their leg straighten on the table
  • the foot is in dorsiflexion
  • the toes will be pointing directly toward the ceiling

Technical factors

  • anteroposterior projection
  • centering point
    • midpoint of the tibia
  • collimation
    • laterally to the skin margins
    • superior to the knee joint
    • inferior to the ankle joint
  • orientation  
    • portrait or diagonal depending on limb length  
  • detector size
    • 35 cm x 43 cm or 43 cm x 35 cm
  • exposure
    • 50-60 kVp
    • 3-5 mAs
  • SID
    • 100 cm
  • grid
    • no

Image technical evaluation

The tibia and fibula are demonstrated in the AP position in their entirety from the knee joint to the ankle.  

The lateral and medial malleoli of the distal fibula and tibia are in profile.

The tibiotalar joint space and the knee joint space are open.

Practical points

This view can be thought of as the literal anteroposterior of the tibia.

Often, this view is requested following major trauma, with a suspected mid-shaft fracture. Keep this in mind when moving the patient as they may be in extreme pain.

Consider the use of a modified horizontal beam if needed.

In some cases the patient's limb will not fit on the one image, it is better to take two images at both points then perform one sub-par projection in the center if both the ankle and the knee joints are not present it is not a complete series.

Radiographic views