I just wanted to conduct a flight back from EDDF-LOWW but after pushback in Frankfurt at gate A21 the elevator was stuck to full down position. When I tried to do a flight controls check the elevator shook a little bit and moved slightly in direction nose up but then smashed back down to the full down position. I then simulated a return-to-stand situation and during taxi the elevator got responsive again but as soon as I slowed down, the elevator literally smashed down in the full down posi