My Spine - Lumbar
Annular tear – This describes the condition where the intervertebral disc has
early damage. The damage comprises of a tear in the annulus fibrosus (see the
chapter Anatomy of the Spine). The tear causes different inflammatory sub-
stances to be released by the body and this can cause local back pain, referred
pain and even radiculopathy (see the chapter Lumbar Slipped Disc).
Disc bulge – This describes the condition where the nucleus pulposus (see the
chapter Anatomy of the Spine) starts to bulge through the damaged annular
fibres.
Disc herniation/ disc extrusion – Both these terms mean that a portion of the
nucleus pulposus has now extended outside of the confines of the annular
fibres into the spinal canal (see the chapter Lumbar Slipped Disc).
Broad-based disc herniation – This is where the disc is damaged extensive-
ly and there is usually a decrease in the height of the disc and the disc looks
a bit like a flat tyre with the whole or a large part of the nucleus projecting
beyond the confines of the annular fibres.
Foraminal disc herniation – In this case the disc herniation is on the side of
the spinal canal where the nerve roots leave the spinal canal through the
foramina. Even relatively small disc prolapses or hernias can cause a lot of
pain or even weakness, as the space is very restricted in this area.
Extraforaminal disc compression – In this instance the nerve is compressed
outside of the spinal canal and outside of the foramen as it leaves on its way
to the leg. This is usually caused by a broad-based disc herniation.
Central disc herniation – This is where the disc herniation is in the middle
of the spinal canal. Since this is a fairly large space, the disc herniation needs
to be fairly large compared with a foraminal disc prolapse before symptoms
occur. In some cases the spinal canal is already partly occluded by facet joint
hypertrophy and compression fro m the ligament inside the spinal canal – the
ligamentum flavum – and even small disc herniations can cause symptoms in
these cases.
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