Degeneration of the
intervertebral disc, often called "degenerative disc
disease" (DDD) of the
spine, is a condition that can be painful and can
greatly affect the quality of one's life. While disc
degeneration is a normal part of aging and for most people
is not a problem, for certain individuals a degenerated disc
can cause severe constant chronic pain.
With symptomatic degenerative disc disease, chronic low
back pain sometimes radiates to the
or there is
pain in the
thighs while walking; sporadic
weakness through the knees may also be evident. Similar
pain may be felt or may increase while sitting, bending,
lifting, and twisting. Chronic neck pain can also be caused
in the upper spine, with pain radiating to the shoulders,
arms and hands.
Neck pain may cause interrupted blood supply to the
brain resulting in headaches, vertigo and worsened cognitive
abilities and memory.
Understanding disc pain
After an injury, some discs become painful because of
inflammation. Some people have nerve endings that penetrate
more deeply into the
annulus fibrosus (outer layer of the disc) than others,
making discs more susceptible to becoming a source of pain.
The scientific community
has the opinion that the healing process involved in the
repair of trauma to the outer annulus results in the
innervation of the resultant scar tissue, and subsequent
pain in the disc, as these nerves become inflamed by
nucleus pulposus material. Degenerative disc disease can
lead to a chronic debilitating condition and can have a
serious negative impact on a person's quality of life. When
pain from degenerative disc disease is severe, traditional
nonoperative treatment is often ineffective.
Degenerative discs typically show degenerative
fibrocartilage and clusters of chondrocytes, suggestive
of repair. Inflammation may or may not be present.
Histologic examination of disc fragments resected for
presumed DDD is routine to exclude
Fibrocartilage replaces the gelatinous mucoid material of
the nucleus pulposus as the disc changes with age. There may
be splits in the annulus fibrosis, permitting herniation of
elements of nucleus pulposus. There may also be shrinkage of
the nucleus pulposus that produces prolapse or folding of
the annulus with secondary osteophyte formation at the
margins of the adjacent vertebral body. The pathologic
findings in DDD include protrusion,
spondylolysis, and/or subluxation of vertebrae (sponylolisthesis)
Often, degenerative disc disease can be successfully
surgery. One or a combination of treatments such as
chiropractic manipulative therapy (CMT) and other
osteopathic manipulation, anti-inflammatory medications
nonsteroidal anti-inflammatory drugs,
spinal injections often provide adequate relief of these
Surgery may be recommended if the conservative treatment
options do not provide relief within two to three months. If
leg or back pain limits normal activity, if there is
weakness or numbness in the legs, if it is difficult to walk
or stand, or if medication or physical therapy are
ineffective, surgery may be necessary, most often
spinal fusion. There are many surgical options for the
treatment of degenerative disc disease. The most common
surgical treatments include:
- Anterior cervical
discectomy and fusion: A procedure that reaches
the cervical spine (neck) through a small incision in the
front of the neck. The intervertebral disc is removed and
replaced with a small plug of bone or other graft
substitute, and in time, that will fuse the vertebrae.
corpectomy: A procedure that removes a portion of
the vertebra and adjacent intervertebral discs to allow
for decompression of the cervical spinal cord and spinal
bone graft, and in some cases a metal plate and
screws, is used to stabilize the spine.
- Dynamic Stabilisation: Following a discectomy,
a stabilisation implant is implanted with a 'dynamic'
component. This can be with the use Pedicle screws (such
as Dynesys or a flexible rod) or an interspinous spacer
with bands (such as a Wallis ligament). These devices off
load pressure from the disc by rerouting pressure through
the posterior part of the spinal column. Like a fusion,
these implants allow maintain mobility to the segent by
allowing flexion and extension.
Facetectomy: A procedure that removes a part of
facet to increase the space.
Foraminotomy: A procedure that enlarges the
vertebral foramen to increase the size of the nerve
pathway. This surgery can be done alone or with a
Laminoplasty: A procedure that reaches the
cervical spine from the back of the neck. The spinal canal
is then reconstructed to make more room for the spinal
Laminotomy: A procedure that removes only a small
portion of the
lamina to relieve pressure on the nerve roots.
- Micro-discectomy: A procedure that removes a
disc through a very small incision using a microscope.
- Percutaneous disc decompression: A procedure
that reduces or eliminates a small portion of the bulging
disc through a needle inserted into the disc, minimally
laminectomy: A procedure for treating
spinal stenosis by relieving pressure on the spinal
cord. A part of the lamina is removed or trimmed to widen
the spinal canal and create more space for the spinal
New treatments are emerging that are still in the
beginning clinical trial phases.
Glucosamine injections are thought to offer some pain
relief for degenerative discs at best, and at worst, do
nothing while also not affecting more aggressive treatment
options. In the US artificial disc replacement is viewed
cautiously as a possible alternative to fusion in carefully
selected patients, yet it is widely used in a broader range
of cases in Europe, where multi-level disc replacement of
the cervical and lumbar spine is common.
Adult stem cell therapies for disc regeneration are in
their infancy. Investigation into
mesenchymal stem cell therapy knife-less fusion of
vertebrae in the United States began in 2006.