What would happen if a person with titanium rods got tazed? Has anybody tried it?

Unrelated. Tazing has no interaction with implanted titanium rods. The only ill effect might be if the rod was in a vulnerable spot, and the sharp muscular jerking in relationship to the application of the tazer, could move the rod in some way. But most tazer hits will not do this although i don't recommend doing tazer for fun.