Limb-sparing surgery for distal femoral and proximal tibial bone lesions: imaging findings with intraoperative correlation.

Objective: Our purpose is to present normal and abnormal imaging findings associated with endoprosthetic reconstruction after limb-salvage surgery.

Conclusion: Endoprosthetic reconstruction varies with the location and size of the tumor, implant designs, and complications. Radiologists need to be aware of associated imaging findings seen in postoperative infection, tumor recurrence, and hardware failure.

Giant cell tumor of bone: review, mimics, and new developments in treatment.

Giant cell tumor (GCT) of bone is generally a benign tumor composed of mononuclear stromal cells and characteristic multinucleated giant cells that exhibit osteoclastic activity. It usually develops in long bones but can occur in unusual locations. The typical appearance is a lytic lesion with a well-defined but nonsclerotic margin that is eccentric in location, extends near the articular surface, and occurs in patients with closed physes.

Tumoral calcinosis: sonographic sedimentation sign.

We present the sonographic findings of tumoral calcinosis in two patients compared with conventional radiography, CT, and MRI. Sonography in both patients demonstrated fluid-sedimentation levels, with more echogenic debris layering dependently. This appearance has been referred to as the "sedimentation sign" on conventional radiography and results from dependent layering of hydroxyapatite crystals within cystic spaces of the lesion.