![](https://fondoscience.com/sites/default/files/styles/figures_tables/public/articles/images/reaca.28171.fs1907031en-figure1.png?itok=ElCnHvup)
Figure 1. View of the right knee from the anteromedial port. Chondral lesion measuring 10 × 10 mm in the external femoral condyle. A: Outerbridge grade II/III chondral lesion; B: lesion curettage with harvesting of subchondral bone; C: performance of microfractures; D: placement of the chitosan matrix (scaffold).