Which two evaluation criteria indicate correct positioning of the lateral knee?

• A. Patella partially obscured, femoral condyles parallel
• B. Femoral condyles superimposed, patella femoral joint space open
• C. Patella positioned laterally, tibia partially visible
• D. Joint space closed, medial condyle obscured

Answer: (B)

The evaluation criteria that indicate correct positioning of a lateral knee radiograph include the superimposition of the femoral condyles and the visibility of the patellofemoral joint space. When the femoral condyles are superimposed, this indicates that the knee is properly rotated, ensuring accurate representation of the joint. An open patellofemoral joint space is essential because it suggests that the patella is correctly positioned in relation to the femur, allowing for optimal visualization of this critical area.

This combination of criteria confirms that the knee is not only positioned correctly but also that the important anatomical relationships are maintained to ensure diagnostic efficacy. A lateral knee view should always highlight these relationships clearly, which is why the presence of an open patellofemoral joint space alongside aligned femoral condyles is vital for accurate assessment.