Workflows in use without a Complete step

We have a workflow in the deviations class that was initially configured without a Complete step in it's workflow. As a result, items that were added to the affected items list and used this workflow appear "Active". I understand workflows cannot be changed after they have been used, but is there any sort of work around, in the back end of the database or some other method to fix this issue for the items that are affected by this issue?