I've seen this glitch referenced on the PC side of things, but I haven't heard if this is happening to anybody else on a console.
In the quest "The Fallen", I've arranged a trap for the dragon Odahviing at Dragonsreach. He responds to my shout, and Dragonrend brings him down onto the palace's main porch. He is quickly trapped, but nothing else happens. He just sits there glaring at me. I can fight him, reducing him to zero health which causes him to rear back (clipping through the dragon trap) before he re-enters the trap animation. At no point in this does it let me speak to him to advance the story.
Does anyone else know what causes this bug, and what (if anything) I can do to move forward? PC players can force a state in the game using a console command, but that's not exactly something we can do on the XBox.