Neck
Pain -
Mechanical Disorders
As
a result of the natural wear and tear that occurs with aging, certain
parts of the cervical spine start to degenerate and wear out, as we
grow older. This process makes some of the anatomic structures of the
cervical spine, the bones, intervertebral discs, ligaments, and muscles
less flexible and less resistant to injury.
Degenerative disc disease (DDD) is part of the natural process of growing
older. Unfortunately, as we age, our intervertebral discs lose their
flexibility, elasticity, and shock absorbing characteristics. The ligaments
that surround the disc, called the annulus fibrosis, become brittle
and they are more easily torn. At the same time, the soft gel-like center
of the disc, called the nucleus pulposus, starts to dry out and shrink.
Degenerative disc disease is as certain as death and taxes, and to a
certain degree this process happens to everyone. However, not everyone
who has degenerative changes in their cervical spine has pain. Many
people who have "normal" necks have MRI's that show disc herniations,
degenerative changes, and narrowed spinal canals. Every patient is different,
and it is important to realize that not everyone develops symptoms as
a result of degenerative disc disease.
There are soft-tissue discs between the bony vertebral bodies in your
cervical spine that are called intervertebral discs. These discs are
composed of a soft gel-like center called the nucleus pulposus, and
a tough outer lining that surrounds the disc called the annulus fibrosis.
The intervertebral disc creates a joint between each of the vertebral
bodies that allows them to flex and extend, rotate slightly, and move
with respect to one another. When the outer lining that surrounds the
disc tears, the soft center squeezes out through the opening, creating
a "herniated", "slipped", or "ruptured disc". Each of these terms describes
the same process.
Myelopathy is a term that means that there is something wrong with the
spinal cord itself. This is usually a later stage of cervical spine
disease, and is often first detected as difficulty walking due to generalized
weakness or problems with balance and coordination. This type of process
occurs most commonly in the elderly, who can have many reasons for having
trouble walking or problems with gait and balance. However, one of the
more worrisome reasons that these symptoms are occurring is that bone
spurs and other degenerative changes in the cervical spine are squeezing
the spinal cord. Myelopathy affects the entire spinal cord, and is very
different from isolated points of pressure on the individual nerve roots.
Doctors use the term radiculopathy to specifically describe pain, and
other symptoms like numbness, tingling, and weakness in your arms or
legs that are caused by a problem with your nerve roots. The nerve roots
are branches of the spinal cord that carry signals out the rest of the
body at each level along the spine. This term comes from a combination
of the Latin word radix, which means the roots of a tree, and the Latin
word pathos, which means a disease. This disease is often caused by
direct pressure from a herniated disc or degenerative changes in the
cervical spine that cause irritation and inflammation of the nerve roots.
Cervical spondylolysis is a disorder that narrows the spinal canal in
the neck compressing the spinal cord or spinal nerve roots. It's a fracture
or defect in the pars anticulars (a portion of the bone between each
of the joints of the back), allowing one vertebral body to slide forward
on the next. Spondylolyosis is sometimes referred to as pars interarticularis
defect. It may be unilateral or bilateral and is usually due to a developmental
defect but may be secondary to a fracture. Spondylolysis affects the
area of the vertebra called the pedicle. The pedicle is part of the
bony ring that protects the spinal nerves, and is the portion that connects
the vertebral body to the facet joints. It's a disease that often times
affects middle-aged and older adults who have degenerative discs and
vertebrae in their neck. When a spondylolysis is present, the back part
of the vertebra and the facet joints simply are not connected to the
body, except by soft tissue.
Stenosis is a term used to describe a narrowing of various parts of
the body. Cervical stenosis is a degenerative disease where the spinal
canal and neural foramina narrow and compress the spinal cord and nerve
roots. Stenosis occurs when pressure increases inflaming the facet joints.
The facet joints are overlapping arches that form the spinal canal.
These joints are covered with cartilage and a membrane. Degenerative
changes and wear and tear can cause the facet joints to inflame. This
disorder is most common in people over 50 years of age. However, genetics
and congenital factors may predispose a person for stenosis.