Grey Turner Sign - Anon

I read about girl who was run over by a truck:

She had a pelvic fracture, displaced humeral fracture,

and Grey Turner sign likely from kidney laceration.

She was in so much pain I almost vasovagal'd,

my friend added, referring to vasovagal syncope,

 the body's reflex of fainting to emotional triggers.

I reread that sentence over and over,

trying to imagine a girl instead of a patient,

searching for an emotional reaction

instead of a clinical one.

Instead, I found myself wondering,

what is a Grey Turner sign?