In the PA axial projection (Camp Coventry method), where should the central ray enter the knee?

In the PA axial projection, also known as the Camp Coventry method, the central ray is directed to enter the knee at the intercondylar fossa. This method is specific for demonstrating the intercondylar region of the femur as well as the crucial structures within the knee joint, such as the anterior and posterior cruciate ligaments.

Positioning the central ray at the intercondylar fossa ensures that the critical anatomy of the knee, especially the bony landmarks located between the femoral condyles, is accurately recorded. It allows for optimal visualization of knee joint pathology, and alignment is crucial for assessment.

For a successful Camp Coventry projection, it is essential to have the knee flexed at about 40 to 50 degrees to maximize the detail of the intercondylar region. By directing the beam here, radiologists can obtain the necessary details that aid in diagnosis and treatment planning.