Presentation
Low back pain. Known malignancy.
Patient Data
Age: 73
Gender: Female
From the case:
Winking owl sign
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Info

The left pedicle of L4 is absent. The right L4 pedicle is present.
Case Discussion
The winking owl sign is given to the appearances on AP projection of the absence of one pedicle of a vertebra body.
It is almost always due to destruction from a metastatic deposit although other causes of pedicular destruction or its congenital absence will give similar appearances.