Kyphosis
Introduction
The 33 vertebrae in the human spine are uniquely aligned to efficiently
support the body. The gentle curves (as seen from the side of the
spine) help the muscles support the body with minimal effort. The
alignment also provides openings for the nerves originating in the
spinal cord to pass out of the spinal column to their destinations.
When a vertebra is not in alignment, many problems may occur.
What is kyphosis?
Kyphosis is a deformity of the spine that results in a segment
of the spine curving (flexing) more than is normal. Because the
vertebrae are no longer stacked properly, the muscle and nerve functions
are disturbed. Symptoms include pain and impaired nerve function,
which can develop slowly or rapidly and may get worse over a period
of time. When excessive, this abnormal flexing may result in a hunchback.
What causes kyphosis?
Kyphosis is caused by the deformity of the vertebra. Kyphosis that
occurs in children is usually due to abnormal development (congenital
or during adolescent growth) or poor posture. In adults, kyphosis
may be caused by fractures to the spine, injury, tumors, infection
,or osteoporosis (deterioration of the bone).
Can kyphosis be prevented?
Not all causes of kyphosis can be prevented, but certain actions
may reduce the possibility of developing kyphosis. These actions
include good posture, good nutrition, consistent and sensible exercise,
avoiding smoking, proper lifting, and accident prevention.
What surgical treatment options exist for kyphosis?
Kyphoplasty for Osteoporotic Fractures
Kyphoplasty is a surgical procedure that treats kyphosis caused
by fractures of the vertebral body caused by osteoporosis or bone
diseases such as multiple myelona. The surgery is minimally invasive,
requiring only a very small incision in the back. A narrow tube
is inserted through the incision using fluoroscopy to guide it into
the correct position in the damaged vertebrae. Using the tube as
a channel, the doctor then guides a special balloon into the vertebral
body.
The balloon is then carefully inflated, restoring the vertebrae
to a more normal shape. The balloon also creates a cavity in the
vertebral body by compacting the soft inner bone material.
The balloon is then deflated and gently removed. Special instruments
are then used to fill the cavity with a soft cement-like material
which quickly hardens to stabilize the vertebrae. With the vertebrae
shape and height restored, the pressure on the nerves is reduced,
easing the pain.
Fusion With Bone Graft
Spinal fusion is a "welding" process by which two or
more of the vertebrae that make up the spinal column are fused together
with bone grafts and internal devices such as metal rods. The surgery
eliminates motion between vertebrae segments. Spinal fusion may
be used to treat abnormal curvatures such as scoliosis or kyphosis.
Bone is the most commonly used material to help promote fusion.
Generally, small pieces of bone are placed into the space between
the vertebrae to be fused. Sometimes larger solid pieces of bone
are used to provide immediate structural support. Bone may come
from the patient (autogenous bone) or a bank of bone harvested from
other individuals (allograft bone). After the fusion procedure has
been performed, the adjacent spinal segments are held immobile to
allow fusion to progress. Immobilization is achieved through internal
fixation devices or external bracing or casting. Both forms of immobilization
may be necessary at times.
Fusion With Instrumentation
Normally, each vertebrae moves with respect to the one above and
below it, allowing the spine to bend and rotate. A fusion means
to fuse the two vertebra so that they cannot move on one another.
Spinal instrumentation is often used to help provide stability for
the spine after vertebrae have been fused together. Common types
of instrumentation include:
- Anterior cervical plates, which can be applied to the front
of the spine.
- Posterior cervical plates, which can be placed on the side
of the spine.
- Posterior cervical wiring, which can be placed around the
spinous processes or the facet joints in the posterior cervical
spine.
- Post-operative cervical braces. Because of their relatively
small size, the cervical spine is well suited for postoperative
braces.
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John
J. Regan, M.D.