@annie1 This treatment is a relatively new (5 years or so) method for managing (not curing) chronic musculo-skeletal pain. It works for some, but not for everyone.

Like any other new treatment, a lot of "Me Too!" vendors have popped up all over the internet - practitioners, qualified and no, sites selling lasers for every ailment you can imagine, even Amazon & eBay.
What you need to know is that not all lasers are created equal, and not all practitioners are well-trained and skilled.

Do your research using scholar.google.com and relying on trusted sources like Mayo, Harvard, Cleveland Clinic and , ask a lot of questions. If you have a good physical therapist for your back, talk to them about laser therapy. I have found my PT's to be excellent sources of information.

What other therapies have you tried?