Dead areas on screen - replace the screen and digitizer cable?

I recently (successfully) replaced the battery and head phone jack. However, now my phone has a dead stripe where the pixels are not responsive. After looking here I think I must have damaged the digitizer cable. Can I replace only the cable or do I need to replace the screen as well? Also, the phone gets pretty warm and the new battery has a crappy life- I imagine there is a short somewhere. Any suggestions.

Thanks - this is a useful forum!