He pulls a face at that imagery Dawn suggests and the laser whirls to life between his fingers. "God no." McCoy had something of a phobia of twentieth century medicine; he regarded the surgeons back in that time as madmen waving their butcher knives, sewing people up like garments, doing more harm than they did good.

"You don't have to do anything except sit still." He watches her closely and then adds: "... Unless you want your ulna grafted to your humerus." It's a joke! McCoy is on fire. Or at least he will be when he is roasting on the flames of hell for that terrible gag only other surgeons would find funny.