A thick piece of paper or tagboard used in the mouth piece of a joint
to support the paper and faciliate easy smoking of said joint.
Damn nigga! You better put a crutch in that little prison J so we can smoke that bitch 'til the wheels fall off it!
"I take sacks to the face whenever I can, don't need no crutch, i get so keyed up, 'til the joint be burnin' my hand" -Luniz, "I Got 5 On It"