My father had back pain, and for a year was shunted off to a physical therapist until finally he had an MRI, which led to a operation on his spine to relieve stenosis. A few years later, he has now developed pain on both hips. Sometimes the pain goes away. He said wearing a belt around his stomach and back helps. So I m wondering - is this still due to his spine? Are things collapsing in there? And how do we find out?
Complete bed rest for a certain period of time is the initial mode of treatment in low back pain. In this case the cause of pain may be restenosis.  You have to consider that low back pain is not always totally curable condition. Pain can be controlled by medication, exercise, weight reduction, lifestyle modification etc. And if the condition is not improving and impairing your activities of daily living then you have options like epidural injection and ultimately surgery. You can think about having an MRI done again.