Since I was a Radiology Resident I have been convinced that the major cause of back pain is arthrosis of the posterior facet joints which are in fact very similar to wear and tear with age and activity in the IP and MP joints of the digits. I am also convinced that most Radiologists pay no attention to this area and focus instead on the condition of discs which may be involved with invisible herniation or on the other hand non-symptomatic even when extremely degenerated. I recall that the Chief of Neurosurgery at the hospital I served served called me to the OR to demonstrate how I had awakened him to the importance of this area which he usually bypassed in his routine surgery.
This consideration may be extremely more important in the age of overdoses of pain drugs when a correct diagnosis is not made at the beginning.