Patient complained of worsening left knee pain. A and B, Anteroposterior and lateral radiographs of left distal femur show lytic lesion with extension to articular surface. C and D, Coronal and axial MR images show extent of lesion within bone and soft tissue. E, Intraoperative photograph after creation of cortical window. F, Tumor removed and cavity enlarged with power burr. G, After treatment with argon beam coagulator, screws are placed to support cement mantle. H, Placement of screws confirmed by image intensifier. I, Bone cement packed in cavity around screws. J and K, Anteroposterior and lateral postoperative radiographs. Fifteen years after surgery, the patient is currently asymptomatic and is employed as a construction worker.