On the extended version, if you go to the part at the end where they're fighting Mordor's army at the Black Gate. After a little while, Aragorn starts to fight a big troll. He gets knocked down and the troll raises his weapon to finish Aragorn off. He has his back to Mordor.

However, on Mt Doom Frodo has just dropped the Ring into the fire. The troll turns his head to see what's going on. He then turns his head back the way it was and takes off running AWAY from Mordor, stepping on where Aragorn is (or should have been).

But when we next see Aragorn, he is lying on the ground in the same place and appears to be pretty healthy, definitely not looking like he'd just been crushed.