Rusty Knuckles 

Similar in VERY FEW regards to "Bloody Knuckles" that we played as kids....

"Rusty Knuckles" is simply (depending on your particular 'acceptance' of said limb) the act of anal fisting.

does this really need an example?

I guess....see goatse.cx for historic reference?

"Oh man, Justin and Andrew were having playtime.....Justin was stretching for his receiving of Andrews clenched fist. I bet he has Rusty Knuckles now!"

Rusty Knuckles by The Italian Job May 18, 2009

Rusty Knuckle 

The act of waking someone up by sticking one's finger in one's rectum, and then shoving said finger into the nostril of the passed out/sleeping individual.

After Tom passed out at the party, John decided to wake him up with a rusty knuckle.

Rusty Knuckle by sancho48879 February 17, 2008

Rusty Moose Knuckle 

The visible remnant on ones love cannon from a freshly pounded fart box...

"Yo, Vinnie d'jou see that rusty moose knuckle on cousin Paulie?"

Rusty Moose Knuckle by th_Pizzle January 18, 2021