The hemipelvis is almost entirely involved, diffusely enlarged, with the cortex thinned, scalloped, and there appears to be old fractures of the pubic rami. The hemipelvis is normally aligned with the normal left side, and the overall size of the right pelvis is similar to the left, suggesting a process that started after skeletal maturity, or did not interfere with the initial growth development of the hip/pelvis and proximal femur.
The Acetabulum is enlarged and thinned, but can still be seen, and is approximately spherical. The acetabulum is proximally located in the pelvis, as if a gradual process of erosion, expansion, protrusion and migration of the center of rotation occurred over a period of years. The process reaches fully to the symphysis pubis, but does not cross it, instead leaving the nearby left pubic symphysis entirely normal. The tumor is best seen in the area of the pubic symphysis on the right, with cortical thinning, expansion, areas of condensation of bone or mineral, and other areas where there is lucency. No periosteal reaction or extraosseous mass is seen, and neither is there any area where the bone is completely destroyed.
On the femoral side, the joint is gone, and an old fracture of the proximal femur/neck is seen, which has resulted in fragmentation and extrusion of the superior portion of the neck and most of the head. However, the proximal femur, up to the level of the greater troch/base of the neck, looks pretty normal in shape and development except for the osteopenia.