Dr Adriaan Liebenberg My Spine Explained | Page 32

CHAPTER 5
LUMBAR SPINAL STENOSIS
What is it?
This condition is characterised by a narrowing of the spinal canal. This leads
to compression and ultimately dysfunction of the spinal nerve roots. Often it
begins with a decrease in the height and weight-carrying ability of the disc.
The collapse of the disc leads to compression of the nerve roots. A combina-
tion of facet joint enlargement and a thickening of the ligamentum flavum
(see the chapter Anatomy of the Spine) cause the compression.
The facet joints enlarge in response to their greater weight-carrying responsi-
bility as the disc deteriorates. There is usually a degree of slippage of the ver-
tebrae on top of one another and the spine can be curved from side to side
(scoliosis) or excessively curved forward (kyphosis) or backward (lordosis).
This is part of the normal ageing process and is called acquired spinal
stenosis. Another term is spondylosis or spinal osteoarthritis. Another type is
that of an inborn abnormality. People who are born with congenital spinal
stenosis have a very small spinal canal. The reason for this is because the
pedicles (see the chapter Anatomy of the Spine) are shorter than normal and
do not allow for sufficient space in the spinal canal.
Spinal stenosis leads to a syndrome of nerve compression that is usually a
slow and progressive disease. Spontaneous remission does not occur as is
sometimes seen in intervertebral disc disease, but there are periods of slow
deterioration interspersed with periods of quick deterioration in a permanent-
ly progressive condition.
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