Clincal information
A 21-year-old woman from Guam presented with a 3-month history of nontraumatic right hip pain together with right lower extremity edema. The patient had bilateral femoral rods placed in 1982 and spinal fusion performed in 1983 to correct a developing kyphoscoliosis and vertebral instability.
Radiographs demonstrated marked osteoporosis with bilateral protrusio acetabuli and the bilateral femoral rods. A large focus of abnormally increased osteosclerosis was present in the right femoral head and neck, extending into the metaphysis as well as into the surrounding soft tissue. An associated pathologic fracture and nonossified soft tissue mass were also demonstrated (Fig. 1).
Transaxial CT images of the pelvis and proximal femur obtained after intravenous contrast injection better defined the aggressive-appearing, densely ossified femoral neck lesion invading the surrounding soft tissue with extensive osseous cortical destruction and a sunburst periosteal reaction (Fig. 2). A radionuclide bone scan, obtained after the injection of 25 mCi (925 MBq) 99mTc-methylene diphosphonate, showed a single focus of markedly abnormal uptake in the proximal right femur. The remainder of the scan was normal.