25-year-old male with a history of sickle cell disease and left-sided AVN presents with decreased joint mobility and right hip pain. There is marked deformity of the right femoral head corresponding to findings seen on recent radiographs. Note is made of increased bone marrow signal abnormality within the right ischium, acetabulum, iliac bone, and femoral head on fluid sensitive sequences with associated decreased signal abnormality on T1-weighted images. There is also increased signal abnormality within the gluteal musculature bilaterally, right greater than left, as well as within the right iliopsoas muscle. These findings likely represent osteonecrosis/bone infarction with surrounding inflammatory change, although infection cannot be completely excluded by this examination. There is a small right-sided joint effusion likely related to the synovitis from the aforementioned osteonecrosis. There is also increased bone marrow signal abnormality on fluid sensitive sequences within the left iliac bone also suggesting osteonecrosis. Note is made of extensive metallic susceptibility artifact corresponding to the orthopedic fixation of the left hip.
Findings most consistent with advanced osteonecrosis resulting in subchondral collapse and severe secondary degenerative changes affecting the right hip. There is inflammatory change in the surrounding musculature as well as synovitis affecting the right hip, also likely related to the aforementioned avascular necrosis, although infection cannot be completely excluded by this examination.