The central ray for a unilateral AP hip projection should enter at the

The central ray for a unilateral AP hip projection should enter at the

• A. Hip joint
• B. Acetabulum
• C. Femoral neck
• D. Mid-shaft

Answer: (C)

Centering the central ray through the femoral neck is essential because it places the proximal femur—the head and neck—in the correct position and scale for evaluation, with minimal distortion and magnification. This trajectory ensures the hip joint and surrounding anatomy are included clearly while keeping the neck lengthwise and well visualized. If the beam instead enters through the hip joint, acetabulum, or mid-shaft, the neck may be off-center, foreshortened, or not adequately demonstrated, compromising assessment of fractures or alignment.

Centering the central ray through the femoral neck is essential because it places the proximal femur—the head and neck—in the correct position and scale for evaluation, with minimal distortion and magnification. This trajectory ensures the hip joint and surrounding anatomy are included clearly while keeping the neck lengthwise and well visualized. If the beam instead enters through the hip joint, acetabulum, or mid-shaft, the neck may be off-center, foreshortened, or not adequately demonstrated, compromising assessment of fractures or alignment.