...to work through. However it is so great to see the radiologist use actual data to describe what is going on! There is the drawback that the dimensions are relative to the size of your spinal structure.

The 4 and 5mm dimensions are over 1/8th of an inch so that is significant even without the relative measurements. What it indicates is that the disk is pushing out enough that there needs to be something done to stop the irritation by the disk rubbing the nerve.

You ask about the MRI reading and how bad it is. It's bad enough to cause you a significant amount of pain so that should alert you that there is a problem. With your on going history with the problem you and your doctor will need to determine the course of action. Try to understand your condition and get some idea about the options. Go to Wikipedia for a start and search on herniated disk.

As to the relationship to a bus pass; personally I'd like to do anything to avoid having to get one but since your condition will most likely require ongoing treatment you could certainly approach your doctor about it.