So a surgeon was rounding at the hospital and needed to catch the elevator before it closed. He stuck his foot into the door, it opened up for him. A medical student on the elevator asked "Why the foot?"
Surgeon replied, "I don't use my foot to operate."
Next floor, an internist waved his hand into the door. "Why the hand?" asked the student.
"I don't need my hands" replied the internist.
Next floor up, the orthopedic surgeon used his head to open the elevator.