My Spine - Lumbar
Images used with permission from Medtronic
Figure 22.3
The drawing on the left demonstrates how the disc space is loosened up with
an instrument after the disc was completely removed. This will allow for the
correct placement of the artificial disc prosthesis. The drawing on the right
demonstrates how the vertebral body is given grooves for the prosthesis keel
to fit in. ot all disc prosthesis have keels.
The top drawing on the opposite page demonstrates the artificial disc pros-
thesis as seen from the side and the bottom drawing as seen from the front,
after it has been placed in position between the vertebrae where the damaged
disc has been removed.
The prosthetic disc has to be placed in the middle of the vertebrae as seen
from the front and has to be placed far enough backwards so that the motion
of that spine segment is normal, without placing it too deeply. If it is placed
to deeply, the prosthesis might push up against the nerves and cause pain or
weakness in the leg and if it is too shallow, it may dislodge towards the front.
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