![](https://mail.fondoscience.com/sites/default/files/styles/figures_tables/public/articles/images/reacae.28373.fs2007040-figure1.png?itok=jXuv2DRn)
View from the arthroscopic anteromedial portal of the right ankle in lateral direction: a mammillated and hyperemic mass is observed, corresponding to pigmented villonodular synovitis in the anterior compartment of the ankle, causing a spatial conflict between the dome of the astragalus and the anterodistal border of the tibia.