User blog comment:Drayco90/Marvel vs. DC- Captain America vs. Batman/@comment-3998231-20111027225213/@comment-143604-20111027235106

The grip is irrelevant, there are straps on the bottom side that very, very securely place it in Cap's arm. It's pretty much designed in a way that the only way to remove it from his hand is by his own doing, or by taking his whole arm off. I'll see if I can find a decent reference picture of what I'm talking about.