Anterior/posterior lumbar fusion
surgery
Sometimes, both an anterior lumbar interbody
fusion and a posterolateral gutter fusion
surgery will be performed and both the
front and back of the spine will be fused.
This anterior/posterior lumbar fusion procedure
is usually done for patients with a high degree
of spinal instability (e.g. fractures), or in
revision surgery (if the initial fusion did not
set up), although some spine surgeons do prefer
the anterior/posterior fusion surgery as a primary
spinal fusion technique.
Fusing both the front and back provides a high
degree of stability for the spine and a large
surface area for the bone fusion to occur. Also,
approaching both sides of the spine often allows
for a more aggressive reduction for patients
who have deformity in the lower back (e.g. isthmic
spondylolisthesis).
Most times, the anterior (from the front) approach
is performed first. By removing the disc material
and cutting the anterior longitudinal ligament
(which lays on the front of the disc space),
the spinal segment is "released" and
allows for a more complete reduction. After the
anterior and the posterior spinal implants are
inserted, this segment is much more stable than
even a normal spine segment.
Some spine surgeons feel that if stabilization
is achieved both through an anterior and a posterior
approach, patients can be mobilized earlier in
the postoperative period. Studies have shown
that fusing both sides of the spine in the lower
back does lead to a very high fusion rate (greater
than 95% of these cases will achieve a solid
fusion).
A drawback of the procedure is that both an anterior
incision in the abdomen and a posterior incision
in the low back need to be done. Some spine surgeons
prefer to achieve anterior and posterior stability
through a PLIF procedure, although there are drawbacks
to approaching the disc space through a posterior
approach (please see the PLIF section).
Spine surgeons with a strong comfort level with
doing ALIF surgery generally prefer an anterior/posterior
approach.
This technique does provide for very high
rates of spinal fusion, but the spine fusion
surgery is quite extensive and carries the
risks inherent in both the ALIF and the posterolateral
gutter fusion procedures.
By: Peter
F. Ullrich, Jr., MD
September 8, 1999 (Updated January 20, 2004) |
