Histology of the plantar fascia employing haematoxylin and eosin (H&E) staining. (A) The sample shows an inflammatory cell infiltrate in the fibrous part of the enthesis with increased vascularity at that site (arrows). The adjacent bone is marked by asterisks. (B) In this sample the osseous part of the enthesis adjacent to the fibrocartilage is disrupted, but the fibrocartilage itself is relatively intact (asterisk). Focal bone defects at sites of fibrocartilage contact with normal bone have been reported in normal insertions (open arrows). There is an inflammatory process in the bone adjacent to the fibrocartilage with increased vascularity (arrows) and proliferation of stromal tissue.