If the fusion is performed in the front of your spine, the surgeon will remove the disc (cushion between vertebrae) and any arthritic areas, and place a bone graft between the vertebrae where it eventually fuses to the surrounding vertebrae to stop abnormal motion. If the fusion is performed in the back of your spine, a bone graft will be placed on the sides of the vertebrae where it will grow together to the vertebrae to stop abnormal motion.
The bone graft may be one of two types: an autograft (bone taken from your own body usually your pelvis) or an allograft (bone from a bone bank). Sometimes metal rods, screws or hooks are also used with the bone graft to further stabilize the spine. This is referred to as "instrumentation."
When the vertebrae have been surgically stabilized, abnormal motion is stopped and function is restored to the spinal nerves.
What are the Reasons for
Lumbar Fusion Surgery?
Lumbar fusion surgery may be indicated for a
variety of lumbar spine problems. Generally,
lumbar spine problems are first treated
conservatively. Then, if low back pain,
numbness, tingling or weakness in the legs does
not improve, some individuals may be candidates
for lumbar spine fusion surgery.
The most common reason for surgery is leg pain or sciatica. This pain may be the result of a herniated lumber disc causing pressure on one or more of the spinal nerves. Leg pain may also be caused by abnormal motion of the vertebrae.
What Conditions are Treated with Lumbar Fusion Surgery?
Spondylolisthesis
In this condition one vertebra has slipped
forward over another. If the vertebra continues
to slip back and forth, the spinal nerves may be
affected, causing leg pain, numbness, tingling
and/or weakness. A spinal fusion may be
recommended to stop this abnormal motion.
Normal and Developmental Defect
Low back pain caused by spondylolisthesis, in which one vertebra slips forward on another, may be due to a development defect or fracture.
Degenerative Disc Disease
In degenerative disc disease, the discs or
cushion pads between your vertebrae shrink,
which can cause abnormal motion and possibly an
unstable area in your spine. As a result, the
vertebrae may compress the spinal nerves,
leading to leg pain.
Arthritis
Severe arthritis of
the spine is called spinal stenosis. As the body
ages, wom vertebrae and discs may develop bony
spurs, which may cause stenosis, or narrowing of
the openings for the spinal cord and nerves.
These spurs irritate the spinal nerve roots and
cause pain, numbness, tingling or weakness down
the legs. Sometimes this condition requires
lumbar fusion surgery to stabilize the spine,
and prevent abnormal motion after pressure on
the spinal nerves is removed.
What are the Potential
Complications of Lumbar Spine Fusion Surgery?
As with any operation,
there are risks involved with spine fusion
surgery. Some patients may develop a distended
abdomen and may not be able to eat. If this
happens, a special tube may be inserted to
relieve the distension.
Another complication is a wound infection. Antibiotics are given before and after the operation to prevent this from occurring.
Urinary problems after spine surgery may include urinary retention and urinary tract infection. A catheter will be placed into your bladder at the time of surgery and will be removed as soon as possible when you are up and around.
Some patients may continue to have pain at the bone graft donor site. If the fusion does not heal, (a condition known as pseudoarthrosis) the instrumentation, such as rods, screws, hooks may break, and further surgery may be required. People who smoke are at a higher risk for pseudoarthrosis complications.
Other complications include phlebitis in your legs and blood clots in your lung. To protect against these problems, you will wear compression boots on your calves during and after surgery.
Rare complications include a failure to improve, worsening neurological symptoms, paralysis and possibly death. Your doctor will discuss these potential risks with you before asking you to sign a consent form.
How is Revision Lumbar
Spine Fusion Surgery Different?
Revision surgery often involves correcting a
deformity caused by a previously failed back
surgery, breakage of instrumentation or
pseudoarthrosis. The type of revision depends on
the problem. The procedure may include operating
on both the front and back of the spine. The
incidence of complications from revision lumbar
spine fusion surgery is higher than in
first-time procedures. It is also more difficult
to relieve pain and restore nerve function in
revision surgery. Patients should be aware that
the chance of having long-term spinal pain is
increased.
