I was a fitness instructor back in the 90's. I had a pretty severe case of plantar faciitis. I taught a lot of step classes. Nothing seemed to help. When I started teaching other types of classes, it went away. The most important thing I learned during my fitness career was what overuse syndrome is. What is it that your wife is doing daily that is causing the pain? It could be a fitness workout repeated to often, or some repetitive movement that is done while at work. Repeating the same movement daily over a long period of time wears on the ligaments, tendons, and joints.