Point is that in the crash the contents may not have been corrupted, it just was saved in the wrong locations.
If you find it, the first thing you should do is compact it, since this, as I understand, correct problems in file structure.
Then transfer the parts to a known good file ie an old back up.
If you find the file unstable, print the material with everything to a PDF file and copy the material from the PDF back to the good database. This should scrub the file of bad characters