Double contour on the lateral femoral condyle: A covert sonographic sign in patellofemoral syndrome?

This is the authors' abstract. We don't add key points for this paper.

The authors declare no conflict of interest. Data sharing is not applicable to this article as no new data were created or analyzed in this study. Video S1. Dynamic ultrasound examination (axial view) shows the hyperechoic lesion overlying the cartilage (C) on the lateral femoral condyle (LFC). Note its close relationship with the patella (P) during probe movements and sono-palpation. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.