Answer to Question 4
“Intervertebral disc (IVD) problems, principally excessive migration of
the nucleus pulposus (NP), -------------- are generally accepted to be one of
the main causes of nonspecific back pain” This is the opening paragraph of one of
the papers (1) from the research in Aberdeen, Scotland based on upright MRI
scans.
I have selected
flexed and extended scans to show the migration.
Note; These scans may not be of the same subject. However this paper (1)
and other papers and presentations, based on the same research, do clearly show
the expected migration of the nucleus on extension and flexion.
If one accepts the hypothesis proposed, then in the “normal” spine there
will never be flexion beyond the parallel sided shape at L4-5 or L5-S, and the
nucleus will always remain anterior in the disk. If for some mechanical reason,
flexion to a wedge shape similar to “Flexed” above, does occur, then the
nucleus will for the first time for that individual migrate posteriorly. It
will then be much closer to the nerves in the posterior annulus. It should be
expected that this will cause pain
(1) The Response of the
Nucleus Pulposus of the Lumbar Intervertebral Discs to Functionally Loaded
Positions Alexander et al SPINE Volume 32, Number 14,