I examined a sick kid who looked like a walking appy, kind of (he looked like one and quacked like one, at least), and when I called the doctor I included "he walks fine and didn't react when I whacked his right foot." My coworker looked at me strangely. I wondered if this had any basis or was voodoo medicine, so I turned to Twitter!
It is NOT voodoo medicine; for a supine patient, if you tap their right foot and jar them a bit and they hit the ceiling, get them into a CT scanner. This is, wait for it, Markle's sign!
There are eponymous signs for everthing, so I knew this must have one, but damned if I could find it, so thanks to @nosokomaniac.
Still, my favorite sign ever is Finklestein's sign, not because of the sign but because of the name. The following conversation occurred once upon a time in an ER near, nearby:
Dr: Oh, yeah, that's Finklestein's sign.
Me: You're full of shit.
Pt: Yeah, I'm on board with that.
Dr: No, seriously! There is a sign! Finklestein found it!
Pt: [Whips out phone, not using sore thumb to type] Sure as shit.