Changes

**Lymphoid and plasma cell infiltration

**Lymphoid and plasma cell infiltration

**Surrounding haemorrhagic areas

**Surrounding haemorrhagic areas

**Macrophages containing [[General Pathology - Pigmentation and Calcification#Haemosiderin|haemosiderin]]

**Macrophages containing [[Pigmentation and Calcification - Pathology#Haemosiderin|haemosiderin]]

**Connective tissue may contain foci of necrosis

**Connective tissue may contain foci of necrosis

**Areas of erosion of peripheral articular cartilage and underlying subchondral bone

**Areas of erosion of peripheral articular cartilage and underlying subchondral bone