I have been having lower back pain for 5 yrs , had MRI in 2007, showed herniated disc between L4&L5, Dr suggested therapy , had therapy for the last 5 yrs, last couple months, gotten worse, another MRI, Dr Suggested surgery to fuse vertebras together, I Can t decide what to do, is fusion safe, will it deteriate other discs, because of more stress . I need some help to what to do?