Imaging in patellofemoral instability: an abnormality-based approach.

Imaging in patellofemoral instability confirms the diagnosis and guides treatment. It is essential to the accurate diagnosis of the root causes and their adequate treatment. A structured approach must be used to identify the factors causing instability, and more than 1 imaging modality may provide similar information. This article revises the acute findings and the abnormalities present in the acute and the chronic settings.