How did you hurt it in the first place?
I would advise a trip to the physiotherapist, maybe pricey but it works!! I paid �30.00 last time I went.
The best cure I can recommend for an ongoing back problem is regular visits to a Yoga teacher and have one on one, do not join a class as that could make things worse, you need a specialist injuries Yoga teacher who can work with you to prevent damage. I was very sceptical about all this Yoga stuff, but cured me after 6 sessions when all others had given up!!!