Discectomy
Anterior cervical discectomy is one of the most common surgical procedures
for problems in the cervical spine. The term discectomy means to "remove
the disc." This procedure is routinely used to relieve pressure on a spinal
nerve or the spinal cord cause by a herniated
disc.
Discectomy is also done when the surgeon intends to fuse two or more bones
of the neck together. This procedure of disc removal and fusion (described
below) is often used to treat degenerative problems (called spondylosis)
in the neck.
In the cervical spine, the disc is usually removed from the front. An incision
is made in the front of the neck beside the trachea (windpipe). The muscles
are moved to the side. The arteries and nerves in the neck are also protected.
Upon reaching the front of the spine, the surgeon uses an X-ray to identify
the correct disc. The problem disc is removed all the way back to the spinal
cord. If any bone spurs are found sticking off the back of the vertebrae
and your surgeon thinks they may also be causing you pain, they may be removed
at the time of surgery. Great care is taken to not damage the spinal cord
and nerve roots. View
animation
Anterior Cervical Fusion
After the disc has been removed between the vertebrae, a cervical fusion
is performed. The space where the disc was taken out is filled with a block
of bone taken from the top rim of the pelvis. Bone taken from your own body
is called autograft. Your surgeon may obtain bone from a source other than
your body, called allograft. This bone is kept in a bone bank. Placing a
bone graft between two or more vertebrae causes the vertebrae to fuse.
Learn
more about the use of bone graft.
View
animation of graft placement.
View
animation of healing fusion.
The anterior cervical fusion may also be done in a way that spreads the
vertebrae apart a bit, trying to restore the space between them. This is
done to recreate the normal height of the disc space and to restore the
normal inward curve of the neck (called lordosis). Increasing the distance
between the vertebrae also widens the opening (foramina) where the nerves
come out of the spine. Restoring the size of the foramina is done to relieve
pressure and irritation from bone spurs where the nerves pass through the
foramina.
Most neck problems are from a degenerative, or aging, condition of the
spine. Degenerative
disc disease and cervical stenosis
are two diagnoses that can lead to pressure on the spinal cord or nerve
roots. Surgery to remove this pressure can be done from the front (anterior)
or back (posterior) of the neck. Doctors use the anterior approach more
often because the pressure is usually on the front portion of the nerves
or spinal cord.
Anterior Interbody Fusion
When an interbody fusion is done, the disc between two vertebrae is removed,
and a bone graft is positioned in its place. As the body heals, the graft
fuses to the vertebrae above and below it. When more than one disc needs
to be removed, a larger bone graft is inserted. Patients usually wear a
brace after the surgery. The brace limits movement between the vertebrae,
increasing the chances for a successful fusion.
Bone heals best when it is held still-without motion between the pieces
trying to heal. The healing of a fusion is no different than healing a fractured
bone, such as a broken arm. However, the neck is one part of the body that
is difficult to hold still, even with a brace worn around the outside of
the neck. Wearing a brace for several months after the surgery can be uncomfortable.
The success of a fusion can also be improved by screwing metal (titanium)
plates or rods to the front of the spine. This holds the vertebrae and graft
rigidly in place while the fusion heals. These implants are referred to
as instrumentation
or internal
fixation. There are many different types of spinal implants used with
the intent of stabilizing the neck and maximizing healing of the fusion.
When doctors use this type of instrumentation, a brace may be needed for
a shorter period of time, or not at all.