Common Mistakes in Imaging: Ligament Injuries of the Knee in Athletes

Assessment of internal derangement is a common indication for imaging of the injured knee in athletes. The first line of imaging is conventional radiography, but magnetic resonance imaging is often required. Radiographic features of ligament injury can be subtle, even when the soft tissue injury is devastating, resulting in instability that may require surgery. Magnetic resonance imaging to assess for ligament injury has several potential pitfalls that can lead to interpretation errors. This article describes common errors when imaging knee ligament injuries in the athlete and discusses strategies to reduce inaccuracies in imaging technique and interpretation. Mistakes on magnetic resonance imaging and radiographs typically arise from the timing of imaging (early/acute versus delayed/chronic), technical factors, potential mimics of pathology, and the inherent limitations of radiography.