Double delta sign (meniscal tear)
lesions: an illustrated review. Sagittal T2-weighted fat-suppressed MR image (a) shows a double delta sign (thin arrow), typical for flipped meniscus. Axial image (b) shows anterior dislocation of the posterior horn of lateral meniscus (thin arrow)
The double delta sign is a feature that has been described in a bucket handle meniscal tear when the inner meniscal fragment flipped anteriorly adjacent to the anterior horn of the donor site and is referred to as a displaced bucket handle tear. The original location of the posterior horn remains empty giving the appearance of a ghost meniscus.