What is the diagnosis?
This is a characteristic appearance of medullary bone infarct.
What is 'double-line sign'? Is it omnipresent in bone infarcts?
On T2W images, a hyperintense ring of granulation tissue, and outer ring of sclerosis, gives rise to 'double-line sign' in bone infarcts or avascular necrosis. This is quite characteristic, but may not be seen in many cases.
A geographic area of altered signal intensity is seen in marrow of distal femur with 'double line sign' on T2W images and peripheral marrow edema on STIR images