The head is flattened and elongated; there is gross osteophytic lipping surrounding the whole head;
cartilage is fissured and shows a nodular appearance; over the anterior part of the articular surface
there is thinning of the cartilage with irregular nodules of cartilage which may be regenerating
cartilage or may be fibrous tissue. The flattening of the head suggests that there may be a
component of ischaemic necrosis allowing collapse.
This 46 year old man was overweight; he had a history of a painful hip for 5 years. There
was pain limitation of movement on internal rotation and associated wasting of the right buttocks