What is X-RAY BOTH KNEE SKYLINE VIEW?

The knee skyline Laurin view is an inferior-superior projection of the patella. It is one of many different methods to obtain an axial projection of the patella.

Indication

This view is used in trauma to assess for a patellar fracture or subluxation and in orthopedics for patellofemoral joint disease. It is best suited to patients able to maintain a semi-recumbent position on the examination table.

Patient position

• the patient is semi-recumbent on the table holding a detector superior of the patella in the landscape orientation
• patient's feet should be very close to the tube side of the bed (see technical factors)
• the knee is bent close to 30°
• often a pillow or cushion should be placed behind the patient to assist them in maintaining this position

Technical factors

• Inferior-Superior Axial Projection
• Centering point
  • the central ray will be angled 160° from the vertical axis (or 30° from horizontal), shooting inferior-superior towards the patella. This will require the tube to lay below the level of the examination table; hence the patient should be as close to this end of the table as possible.
  • the apex of the patella
• Collimation
  • laterally to include the skin margins of the knee
  • inferior to include the femoropatellar joint space
  • superior to include medial skin margin
• Orientation
  • Landscape
• Detector Size
  • 18 cm x 24 cm
• Exposure
  • 60-70 kVp
  • 7-10 mAs
• SID
  • 100-120 cm
• Grid
  • No