There is an irregular fracture line with sclerotic bands and trabecular disorganization in the right sacral ala, lateral to the sacral foramina, parallelling the sacroiliac joint with ventral cortical disruption. A small adjacent bone fragment is seen anteriorly. Similar, but more subtle findings are seen in the left sacral ala at the S2 level, with buckling of the anterior cortex of the S2 vertebral body. The appearances are suggestive of sacral insufficiency fractures, likely healing/subacute given the sclerosis.
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