Osteonecrosis of bone is a progressive disease affecting the areas with precarious blood supply like head of the femur, head of the humerus, Scaphoid, Talus, Navicular, Condyles of long bones etc. Causes are mostly unknown and few are related to Corticosteroids, Trauma, Alcoholism, and hematological disorders. In the present study, 45 symptomatic patients were evaluated for osteonecrosis using X Ray, CT Scan and MRI in a tertiary care hospital. The age of incidence, gender variability, laterality, involvement of the different bones were studied. The sensitivity of various imaging modalities according to the disease stages was also noted. In majority of the cases the cause was unknown and the head of the femur came out to be the most involved site. MRI was found to be the most sensitive imaging modality followed by CT and X ray. The common findings detected by X ray and CT were Sclerosis, Subchondral lucency, Altered morphology and associated degenerative changes. Bone marrow edema was the most common finding detected by MRI in very early stage. Joint effusion, Double line sign, subchondral collapse, degenerative changes of the joint were other significant findings. T1 hyposensitivity was the main finding in the osteonecrosis of Scaphoid, Navicular and Talus with no enhancement post contrast.
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