Greetings, not to get worried. Just get massage by either physio or ayurveda. Back pain will be resolved with these. Forget about sciatica, this is a term just to terrify you.
Next Steps
if trigger point therapy is done by physio you can see instant results and in couple of sessions your grandfather will be pain free. but remember exercise need to be followed to overcome back issues. physio will recommend exercise. for doing exercise age is no hindrance.
Health Tips
if any questions do get back. surgery is not required, just forget it.