I'm a physical therapist so I see patients with back pain all day long. Has she tried any physical therapy? It's possible she can get significant relief with proper manual therapy combined with a supervised exercise program targeted to her specific needs. So many things can be causing the pain in her back (I see degenerative disc disease and spinal stenosis as the most frequent cause in the elderly where I work.) Plus movement is going to be really helpful. Gentle walking and movement. Yoga, pilates, and other movement programs are showing increasing evidence to help pain throughout the body in all age groups.