InDesign crashed and file appears corrupted

It won't help you now - but for the future:

1.  At least once a day do SAVE AS with a new name, 
2.  At the end of the day - export your file as IDML, 
3.  Pack both files and save remotely - server / cloud / FTP server /   pendrive / external drive / whatever - it will be your backup in case #£_% hit the fan 😉 of course you should also save in the same place all your links and fonts - and then update them when anything changes - or just do Package. 

If you have never done 1. and only Ctrl+S - InDesign is always storing in the INDD file Undo history. Unfortunately, this history is only available till you close your document - BUT is saved and kept in the file - so your file keeps getting bigger and bigger "for no reason".

Save As cleans old file from this unaccessible data.

IDMLing - 2. - is even better - fixes all potential glitches that may be present in your INDD file - housekeeping.

Try exporting the damaged file to IDML, then open & resave with a new name. Can you relink then?