Answer to Question 2
The therapy, which corresponds most closely to this interpretation of the problem, is the McKenzie Therapy. This is taught inside the physiotherapy profession. Robin McKenzie was a physiotherapist. His book “Treat Your Own Back” is well known to all those treating back pain. The typical exercise of the McKenzie system is what I call the “floppy press up”
This will tend to restore the wedge shape of the lowest lumbar discs where this has been lost for whatever reason. I look upon this as a very important bit of evidence. Although I am qualified as a chiropractor, I am trained in Mackenzie by the Mackenzie Institute UK and I use it in most acute back pain cases of recent onset. In the trial published in the BMJ in 1990, neither manipulative physiotherapy nor chiropractic was particularly effective in the early stages of an acute LBP attack. This is exactly when Mackenzie is most effective. It can completely stop the attack in its tracks. If the person is careful with sitting and uses my pelvic supports when driving they can be back to square one quite quickly. My interpretation is that the Mackenzie extension exercise squeezes the nucleus back to the anterior of the disk where it should be all the time in L 4 5 or 5 S.
P S Although the Mackenzie extension exercise works well I find it even more effective to apply the extension force directly to the pelvis, rather than using the legs as lever. With the patient supine I put a cushion under the knees to take the tension out of the psoas and then I lift the iliac crest on each side with both my hands. I pull upwards and towards the patient's feet to apply an extension plus tension to the lumbo sacral junction area. For a light person where I can apply sufficient force this is much more effective than standard Mackenzie. Sometimes I, and the patient, can feel the nucleus oozing back to where it should be!