Which radiographic feature on an AP view indicates a spondylolisthesis?

Prepare for the Bodalia Exam with engaging quiz questions. Explore multiple choice questions, hints, and explanations to boost your readiness. Aim for success!

Multiple Choice

Which radiographic feature on an AP view indicates a spondylolisthesis?

The key idea is that spondylolisthesis is forward slipping of a vertebral body over the one below, and on an AP view this forward displacement can create a silhouette that resembles an inverted Napoleon hat. This inverted Napoleon hat sign is a classic radiographic appearance indicating listhesis on the AP projection—the anterior edge of the slipped vertebra forms a triangular shape that points downward, like an inverted hat. The other signs come from different contexts: the Scotty dog sign appears on oblique views and marks a pars interarticularis defect, not forward slippage seen on AP. The butterfly sign and sphinx sign aren’t standard AP indicators of spondylolisthesis.

The key idea is that spondylolisthesis is forward slipping of a vertebral body over the one below, and on an AP view this forward displacement can create a silhouette that resembles an inverted Napoleon hat. This inverted Napoleon hat sign is a classic radiographic appearance indicating listhesis on the AP projection—the anterior edge of the slipped vertebra forms a triangular shape that points downward, like an inverted hat.

The other signs come from different contexts: the Scotty dog sign appears on oblique views and marks a pars interarticularis defect, not forward slippage seen on AP. The butterfly sign and sphinx sign aren’t standard AP indicators of spondylolisthesis.

More practice questions