THR: aggresive granumomatous disease

Also known as cement disease, particle disease, aggresive osteolysis
Extensive bone resorption due to hypersentitivity and gaint cell reaction

Radiograph:
Well defined lytic lesions, which do not follw the shape of the prosthesis
Common at the tip or medial border of the femoral component
Also seen in acetabulum

References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications