CAMRT Radiography Practice Exam

What condition contraindicates an inferosuperior projection of the patella?

1. A fracture of the femur

2. A transverse fracture of the patella

3. An anterior cruciate ligament injury

4. Patellar dislocation

The correct answer is: A transverse fracture of the patella

The inferosuperior projection of the patella is oriented to visualize the patella in relation to the femur from below and requires proper alignment of both structures. A transverse fracture of the patella fundamentally compromises its structural integrity and alignment, making it unsuitable for an inferosuperior projection. This projection relies on the patella being in its normal anatomical position; a fracture can lead to displacement or misalignment of the patella, which would obstruct clear visualization. Using this projection in the presence of a transverse fracture could exacerbate the injury or result in diagnostic errors, as the fracture plane might prevent accurate imaging of both the patella and the femur. Other conditions such as a fracture of the femur, an anterior cruciate ligament injury, or a patellar dislocation may complicate the projection but do not inherently counteract the positional requirements as severely as a transverse fracture of the patella does.