Download What is degenerative disc disease? What are the symptoms?

Degenerative Disc Disease & Sciatica
Medical Author: William C. Shiel Jr., MD, FACP, FACR
How is the spine designed?
What is the purpose of the spine and its discs?
What is degenerative disc disease? What are the symptoms?
What are radiculopathy and sciatica? What are the symptoms?
How is radiculopathy diagnosed?
How is radiculopathy treated?
What is bony encroachment and spinal stenosis?
Degenerative Disc Disease & Sciatica At A Glance
How is the spine designed?
The vertebrae are the bony building blocks of the spine. Between each of the largest
part of the vertebrae are the discs. Ligaments are situated around the spine and discs.
The spine has seven vertebrae in the neck (cervical vertebrae), 12 vertebrae in the midback (thoracic vertebrae), and five vertebrae in the low back (lumbar vertebrae). In
addition, in the mid-buttock, beneath the fifth lumbar vertebra, is sacrum followed by the
tailbone (coccyx).
What is the purpose of the spine and its discs?
The bony spine is designed so that vertebrae "stacked" together can provide a movable
support structure while also protecting the spinal cord (nervous tissue that extends down
the spinal column from the brain) from injury. Each vertebra has a spinous process,
which is a bony prominence behind the spinal cord that shields the cord's nerve tissue.
The vertebrae also have a strong bony "body" in front of the spinal cord to provide a
platform suitable for weight-bearing.
The discs are pads that serve as "cushions" between each vertebral body that serve to
minimize the impact of movement on the spinal column. Each disc is designed like a jelly
donut with a central softer component (nucleus pulposus). This softer component can
rupture (herniate) through the surrounding outer ring (annulus fibrosus) and irritate
adjacent nervous tissue. Ligaments are strong fibrous soft tissues that firmly attach
bones to bones. Ligaments attach each of the vertebrae and surround each of the discs.
When ligaments are injured as the disc degenerates, localized pain in the area affected
can result.
What is degenerative disc disease? What are the symptoms?
As we age, the water and protein content of the cartilage of the body changes. This
change results in weaker, more fragile and thin cartilage. Because both the discs and
the joints that stack the vertebrae (facet joints) are partly composed of cartilage, these
areas are subject to wear and tear over time (degenerative changes). The gradual
deterioration of the disc between the vertebrae is referred to as degenerative disc
disease. Wear of the facet cartilage and the bony changes of the adjacent joint is
referred to as degenerative facet joint disease or osteoarthritis of the spine.
Degeneration of the disc is medically referred to as spondylosis. Spondylosis can be
noted on x-ray tests or MRI scanning of the spine as a narrowing of the normal "disc
space" between the adjacent vertebrae.
Degeneration of the disc tissue makes the disc more susceptible to herniation.
Degeneration of the disc can cause local pain in the affected area. Any level of the spine
can be affected by disc degeneration. When disc degeneration affects the spine of the
neck, it is referred to as cervical disc disease. When the mid-back is affected, the
condition is referred to as thoracic disc disease. Disc degeneration that affects the
lumbar spine is referred to as lumbago. Lumbago causes pain localized to the low back
and is common in older people. Degenerative arthritis (osteoarthritis) of the facet joints is
also a cause of localized lumbar pain that can be detected with plain x-ray testing. The
pain from degenerative disc or joint disease of the spine is usually treated conservatively
with intermittent heat, rest, rehabilitative exercises, and medications to relieve pain,
muscle spasm, and inflammation.
What are radiculopathy and sciatica? What are the symptoms?
Radiculopathy refers to nerve irritation caused by damage to the disc between the
vertebrae. This occurs because of degeneration ("wear and tear") of the outer ring of the
disc or because of traumatic injury, or both. Weakness of the outer ring leads to disc
bulging and herniation. As a result, the central softer portion of the disc can rupture
through the outer ring of the disc and abut the spinal cord or its nerves as they exit the
bony spinal column.
When nerves are irritated in the neck from degenerative disc disease, the condition is
referred to as cervical radiculopathy. This can lead to painful burning or tingling
sensations in the arms. When nerves are irritated in the low back from degenerative disc
disease, the condition is called lumbar radiculopathy, and it often causes the commonly
recognized "sciatica" pain that shoots down a lower extremity. This condition can be
preceded by a localized low-back aching. Sciatica pain can follow a "popping" sensation
at onset and be accompanied by numbness and tingling. The pain commonly increases
with movements at the waist and can increase with coughing or sneezing. In more
severe instances, lumbar radiculopathy can be accompanied by incontinence of the
bladder and/or bowels.
How is radiculopathy diagnosed?
Radiculopathy is suspected when the symptoms described above are noted. The doctor
can sometimes detect signs of irritated nerves during the examination. For example,
increased radiating pain when the lower extremity is lifted supports the diagnosis of
lumbar radiculopathy. Nerve testing (EMG/electromyogram and NCV/nerve conduction
velocity) of the lower extremities can be used to detect the nerve irritation. The actual
disc herniation can be detected with radiology testing, such as CAT or MRI scanning.
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Pictures of an MRI of the spine
This patient had a herniated disc between vertebrae L4 and L5. The resulting surgery
was a discectomy
Picture of herniated disc between L4 and L5
Cross-section picture of herniated disc between L4 and L5
How is radiculopathy treated?
The treatment of radiculopathy ranges from nonsurgical (medical) management to
surgery. Medical management of radiculopathy includes patient education of the
condition, medications to relieve pain and muscles spasm, cortisone injection around the
spinal cord (epidural injection), physical therapy (heat, massage, ultrasound, electrical
stimulation), and rest (not strict bed rest, but avoiding re-injury). With unrelenting pain,
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severe impairment of function, or incontinence (which can indicate spinal cord irritation),
surgery may be necessary. The operation performed depends on the overall status of
the spine and the age and health of the patient. Procedures include removal of the
herniated disc with laminotomy (producing a small hole in the bone of the spine
surrounding the spinal cord), laminectomy (removal of the bony wall adjacent to the
nerve tissues), by needle technique through the skin (percutaneous discectomy), discdissolving procedures (chemonucleolysis), and others.
What is bony encroachment and spinal stenosis?
Any condition that results in movement or growth of the bony vertebrae of the spine can
limit the space (encroachment) for the adjacent spinal cord and nerves. Causes of bony
encroachment of the spinal nerves include foramen narrowing (narrowing of the portal
through which the spinal nerve passes from the spinal column, out of the spinal canal to
the body), spondylolisthesis (slipping of one vertebra relative to another), and spinal
stenosis (narrowing of the spinal canal caused by compression of the nerve roots or
spinal cord by bony spurs or other soft tissues in the spinal canal). For example, lumbar
spinal nerve compression in these conditions can lead to sciatica pain that radiates
down the lower extremities.
Spinal stenosis (narrowing of the spinal canal) can occur at any level of the spine, but
it's most common in the lumbar spine of the low back. Symptoms depend on the level
affected. For example, lumbar spinal stenosis can cause lower-extremity pains which
worsen with walking and are relieved by resting (mimicking poor circulation of the lower
extremities).
Treatment of these conditions varies (depending on the severity and condition of the
patient) from rest to surgical decompression by removing the bone that is compressing
the nervous tissue.
Degenerative Disc Disease & Sciatica At A Glance
The discs of the spine serve as "cushions" between each vertebral segment.
The discs are designed somewhat like a jelly donut.
Degeneration (deterioration) of the disc makes the disc more susceptible to
herniation (rupture) which can lead to localized or radiating pain.
Sciatica can result from disc herniation when nerves of sensation in the low back
are irritated.
Degenerative Disc Disease & Sciatica Glossary of Terms
Adjacent: Lying nearby. Related terms include superjacent,
circumjacent. From ad-, near + the Latin jacere, to lie = to lie near.
subjacent,
and
Annulus: A ringlike structure, or any body part that is shaped like a ring. Applied to
many small ring-shaped structures. See the entire definition of Annulus
Arms: An appendage in anatomy and in clinical trials. See: Arm.
Arthritis: Inflammation of a joint. When joints are inflamed they can develop stiffness,
warmth, swelling, redness and pain. There are over 100 types of arthritis. (see
osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, lupus, gout,
pseudogout).
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Bladder: Any pouch or other flexible enclosure that can hold liquids or gases but usually
refers to the hollow organ in the lower abdomen that stores urine -- the urinary bladder.
The kidneys filter waste from the blood and produce urine, which enters the bladder
through two tubes called ureters. Urine leaves the bladder through another tube, the
urethra . In women, the urethra is a short tube that opens just in front of the vagina . In
men, it is longer, passing through the prostate gland and then the penis . Infection of the
bladder is called cystitis. See the entire definition of Bladder
Bone: Bone is the substance that forms the skeleton of the body. It is composed chiefly
of calcium phosphate and calcium carbonate . It also serves as a storage area for
calcium, playing a large role in calcium balance in the blood. See the entire definition of
Bone
Brain: That part of the central nervous system that is located within the cranium ( skull ).
The brain functions as the primary receiver, organizer and distributor of information for
the body. It has two (right and left) halves called "hemispheres." See the entire definition
of Brain
Cartilage: Firm, rubbery tissue that cushions bones at joints. A more flexible kind of
cartilage connects muscles with bones and makes up other parts of the body, such as
the larynx and the outside parts of the ears.
Cervical: Having to do with any kind of neck including the neck on which the head is
perched and the neck of the uterus. The word "cervix" in Latin means "neck". That is
why cervical vertebrae and cervical cancer involve quite disparate parts of the anatomy
joined only by the meaning of the word "cervix". See the entire definition of Cervical
Cervical disc: A disk shaped piece of specialized tissue that separates the vertebral
bones of the spinal column in the neck. See the entire definition of Cervical disc
Cervical vertebrae: The cervical (neck) vertebrae are the upper 7 vertebrae in the
spinal column (the vertebral column). They are designated C1 through C7 from the top
down. See the entire definition of Cervical vertebrae
Circulation: The movement of fluid in a regular or circuitous course. Although the noun
"circulation" does not necessarily refer to the circulation of the blood, for all practical
purposes today it does. Heart failure is an example of a problem with the circulation.
Compression:
1. The act of pressing together. As in a compression fracture, nerve compression, or
spinal cord compression.
2. To shorten in time. In embryology, there may be compression of development with
some stages even omitted.
Condition: The term "condition" has a number of biomedical meanings including the
following:
1. An unhealthy state, such as in "this is a progressive condition."
2. A state of fitness, such as "getting into condition."
3. Something that is essential to the occurrence of something else; essentially a
"precondition."
4. As a verb: to cause a change in something so that a response that was previously
associated with a certain stimulus becomes associated with another stimulus; to
condition a person, as in behavioral conditioning.
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Cortisone: An adrenocorticoid hormone , a naturally occurring hormone made by and
secreted by the adrenal cortex , the outer part (the cortex ) of the adrenal gland .
See the entire definition of Cortisone
Decompression: 1. In general, the removal of pressure. 2. In surgery, a procedure to
remove pressure on a structure, as in decompression of the spinal cord. 3. The
lessening of atmospheric pressure on deep-sea divers returning to the surface, or on
persons ascending to great heights.
Degenerative arthritis: Also known as osteoarthritis, this type of arthritis is caused by
inflammation, breakdown and eventual loss of the cartilage of the joints. Among the over
100 different types of arthritis conditions, osteoarthritis is the most common, affecting
usually the hands, feet, spine, and large weight-bearing joints, such as the hips and
knees. Also called degenerative joint disease.
Diagnosis: 1 The nature of a disease ; the identification of an illness. 2 A conclusion or
decision reached by diagnosis. The diagnosis is rabies . 3 The identification of any
problem. The diagnosis was a plugged IV. See the entire definition of Diagnosis
Disc: Shortened terminology for an intervertebral disc, a disk-shaped piece of
specialized tissue that separates the bones of the spinal column. See the entire
definition of Disc
Disease: Illness or sickness often characterized by typical patient problems (symptoms)
and physical findings (signs). Disruption sequence: The events that occur when a fetus
that is developing normally is subjected to a destructive agent such as the rubella
(German measles) virus.
Epidural: Outside the dura, the outermost, toughest, and most fibrous of the three
membranes (meninges) covering the brain and the spinal cord. An epidural hematoma is
a collection of blood beneath the skull but outside the dura.
Extremity: The extremities in medical language are not freezing cold or scorching heat
but rather the uttermost parts of the body. The extremities are simply the hands and feet.
See the entire definition of Extremity
Health: As officially defined by the World Health Organization, a state of complete
physical, mental, and social well-being, not merely the absence of disease or infirmity.
Herniation: Abnormal protrusion of tissue through an opening. For example, a
intervertebral disk (one situated between the vertebral bodies) can protrude and impinge
on a nerve root.
Incontinence: Inability to control excretions. Urinary incontinence is inability to keep
urine in the bladder. Fecal incontinence is inability to retain feces in the rectum.
Indicate: In medicine, to make a treatment or procedure advisable because of a
particular condition or circumstance. For example, certain medications are indicated for
the treatment of hypertension during pregnancy while others are contraindicated.
Inflammation: A basic way in which the body reacts to infection , irritation or other
injury, the key feature being redness, warmth, swelling and pain . Inflammation is now
recognized as a type of nonspecific immune response. See the entire definition of
Inflammation
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Injury: Harm or hurt. The term "injury" may be applied in medicine to damage inflicted
upon oneself as in a hamstring injury or by an external agent on as in a cold injury. The
injury may be accidental or deliberate, as with a needlestick injury. The term "injury" may
be synonymous (depending on the context) with a wound or with trauma.
Joint: A joint is the area where two bones are attached for the purpose of motion of
body parts. A joint is usually formed of fibrous connective tissue and cartilage. An
articulation or an arthrosis is the same as a joint. See the entire definition of Joint
Laminectomy: A surgical procedure in which the posterior arch of a vertebra is
removed. Laminectomy is done to relieve pressure on the spinal cord or on the nerve
roots that emerge from the spinal canal. The procedure may be used to treat a slipped
or herniated disk or to treat spinal stenosis.
Lumbar: Referring to the 5 lumbar vertebrae which are situated below the thoracic
vertebrae and above the sacral vertebrae in the spinal column. The 5 lumbar vertebrae
are represented by the symbols L1 through L5. There are correspondingly 5 lumbar
nerves.
Lumbar radiculopathy: Nerve irritation caused by damage to the discs between the
vertebrae. Damage to the disc occurs because of degeneration ("wear and tear") of the
outer ring of the disc, traumatic injury, or both. As a result, the central softer portion of
the disc can rupture (herniate) through the outer ring of the disc and abut the spinal cord
or its nerves as they exit the bony spinal column. This rupture is what causes the
commonly recognized pain of "sciatica" that shoots down the leg.
See the entire definition of Lumbar radiculopathy
Lumbar vertebrae: There are 5 lumbar vertebrae. The lumbar vertebrae are situated
between the thoracic vertebrae and the sacral vertebrae in the spinal column. The 5
lumbar vertebrae are represented by the symbols L1 through L5.
Massage: The manipulation of muscle and connective tissue to enhance the function of
those tissues and promote relaxation and well-being. Therapeutic massage can ease
tension and reduce pain. Massage can be a part of physical therapy or practiced on its
own. It can also be highly effective for reducing the symptoms of arthritis, back pain,
carpal tunnel syndrome, and other disorders of the muscles and/or nervous system.
MRI: Abbreviation and nickname for magnetic resonance imaging. For more information,
see: Magnetic Resonance Imaging; Paul C. Lauterbur; Peter Mansfield.
Muscle: Muscle is the tissue of the body which primarily functions as a source of power.
There are three types of muscle in the body. Muscle which is responsible for moving
extremities and external areas of the body is called "skeletal muscle." Heart muscle is
called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called
"smooth muscle."
Neck: The part of the body joining the head to the shoulders. Also, any narrow or
constricted part of a bone or organ that joins its parts as, for example, the neck of the
femur bone. See the entire definition of Neck
Nerve: A bundle of fibers that uses chemical and electrical signals to transmit sensory
and motor information from one body part to another. See: Nervous system.
Nerve compression: "Pinching" a nerve by putting too much pressure on it. For
example, the sciatic nerve may be painfully compressed by a ruptured disc in the lower
spine causing sciatica. See the entire definition of Nerve compression
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Nucleus: 1) In cell biology, the structure that houses the chromosomes. 2) In
neuroanatomy, a group of nerve cells.
Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for
example, the onset of rheumatoid arthritis . There is always an onset to a disease but
never to the return to good health. The default setting is good health.
See the entire definition of Onset
Operation: Although there are many meanings to the word "operation", in medicine it
refers to a surgical procedure. See the entire definition of Operation
Osteoarthritis: A type of arthritis caused by inflammation, breakdown, and eventual
loss of cartilage in the joints. Also known as degenerative arthritis.
Pain: An unpleasant sensation that can range from mild, localized discomfort to agony.
Pain has both physical and emotional components. The physical part of pain results
from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it
can be more diffuse, as in disorders like fibromyalgia . Pain is mediated by specific
nerve fibers that carry the pain impulses to the brain where their conscious appreciation
may be modified by many factors. See the entire definition of Pain
Percutaneous: Through the skin, as in a percutaneous biopsy.
Protein: A large molecule composed of one or more chains of amino acids in a specific
order determined by the base sequence of nucleotides in the DNA coding for the
protein. See the entire definition of Protein
Radiculopathy: Any disease of the spinal nerve roots and spinal nerves. It is
synonymous with radiculitis. See the entire definition of Radiculopathy
Radiology: The branch of medicine that uses ionizing and nonionizing radiation for the
diagnosis and treatment of disease. See the entire definition of Radiology
Rest: 1. Repose. Relaxation. 2. A fragment of embryonic tissue that has been retained
after the period of embryonic development. Also called an embryonic rest.
Rupture: A break or tear in any organ (such as the spleen) or soft tissue (such as the
achilles tendon). Rupture of the appendix is more likely among uninsured and minority
children when they develop appendicitis.
Sciatica : Pain resulting from irritation of the sciatic nerve, typically felt from the low
back to behind the thigh and radiating down below the knee. While sciatica can result
from a herniated disc directly pressing on the nerve, any cause of irritation or
inflammation of this nerve can reproduce the painful symptoms of sciatica. Diagnosis is
by observation of symptoms, physical and nerve testing, and sometimes by X-ray or MRI
if a herniated disk is suspected. See the entire definition of Sciatica
Sensation: In medicine and physiology , sensation refers to the registration of an
incoming ( afferent ) nerve impulse in that part of the brain called the sensorium , which
is capable of such perception. Therefore, the awareness of a stimulus as a result of its
perception by sensory receptors. (Sensory is here synonymous with sensation.)
See the entire definition of Sensation
Skin: The skin is the body's outer covering. It protects us against heat and light, injury,
and infection. It regulates body temperature and stores water, fat, and vitamin D.
Weighing about 6 pounds, the skin is the body's largest organ. It is made up of two main
layers; the outer epidermis and the inner dermis. See the entire definition of Skin
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Spasm: A brief, automatic jerking movement. A muscle spasm can be quite painful, with
the muscle clenching tightly. A spasm of the coronary artery can cause angina. Spasms
in various types of tissue may be caused by stress, medication, over-exercise, or other
factors.
Spinal cord: The major column of nerve tissue that is connected to the brain and lies
within the vertebral canal and from which the spinal nerves emerge. Thirty-one pairs of
spinal nerves originate in the spinal cord: 8 cervical , 12 thoracic , 5 lumbar, 5 sacral,
and 1 coccygeal. The spinal cord and the brain constitute the central nervous system (
CNS ). The spinal cord consists of nerve fibers that transmit impulses to and from the
brain. Like the brain, the spinal cord is covered by three connective-tissue envelopes
called the meninges . The space between the outer and middle envelopes is filled with
cerebrospinal fluid ( CSF ), a clear colorless fluid that cushions the spinal cord against
jarring shock. Also known simply as the cord. See the entire definition of Spinal cord
Spinal nerve: One of the nerves
See the entire definition of Spinal nerve
that
originates
in
the
spinal
cord
.
Spinal stenosis: Narrowing of the spaces in the spine, resulting in compression of the
nerve roots or spinal cord by bony spurs or soft tissues, such as disks, in the spinal
canal. This occurs most often in the lumbar spine (in the low back) but also occurs in the
cervical spine (in the neck) and less often in the thoracic spine (in the upper back).
See the entire definition of Spinal stenosis
Spine: 1) The column of bone known as the vertebral column, which surrounds and
protects the spinal cord. The spine can be categorized according to level of the body:
i.e., cervical spine (neck), thoracic spine (upper and middle back), and lumbar spine
(lower back). See also vertebral column. 2) Any short prominence of bone. The spines of
the vertebrae protrude at the base of the back of the neck and in the middle of the back.
These spines protect the spinal cord from injury from behind.
Spinous process: A slender projection from the back of a vertebra to which muscles
and ligaments are attached.
Spondylolisthesis: Forward movement of one of the building blocks ( vertebrae ) of the
spine in relation to an adjacent vertebra . See the entire definition of Spondylolisthesis
Spondylosis: Degeneration of the disc spaces between the vertebrae. This finding in
the spine is commonly associated with osteoarthritis. See the entire definition of
Spondylosis
Stenosis: A narrowing, as in:
aortic stenosis (narrowing of the aortic valve of the heart),
pulmonary stenosis (narrowing of the pulmonary valve of the heart),
pyloric stenosis (narrowing of the outlet of the stomach), and
spinal stenosis (narrowing of the vertebral canal).
See the entire definition of Stenosis
Surgery: The word "surgery" has multiple meanings. It is the branch of medicine
concerned with diseases and conditions which require or are amenable to operative
procedures. Surgery is the work done by a surgeon. By analogy, the work of an editor
wielding his pen as a scalpel is s form of surgery. A surgery in England (and some other
countries) is a physician's or dentist's office. See the entire definition of Surgery
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Tear: A drop of the salty secretion of the lacrimal glands which serves to moisten the
conjunctiva and cornea.
Therapy: The treatment of disease . See the entire definition of Therapy
Thoracic: Pertaining to the chest.
Thoracic vertebrae: The 12 thoracic vertebrae are situated between the cervical (neck)
vertebrae and the lumbar vertebrae. The thoracic vertebrae are represented by the
symbols T1 through T12. See the entire definition of Thoracic vertebrae
Tissue: A tissue in medicine is not like a piece of tissue paper. It is a broad term that is
applied to any group of cells that perform specific functions. A tissue in medicine need
not form a layer. Thus,
The bone marrow is a tissue;
Connective tissue consists of cells that make up fibers in the framework
supporting other body tissues; and
Lymphoid tissue is the part of the body's immune system that helps protect it from
bacteria and other foreign entities.
Ultrasound : High-frequency sound waves. Ultrasound waves can be bounced off of
tissues using special devices. The echoes are then converted into a picture called a
sonogram. Ultrasound imaging, referred to as ultrasonography, allows physicians and
patients to get an inside view of soft tissues and body cavities, without using invasive
techniques. Ultrasound is often used to examine a fetus during pregnancy. There is no
convincing evidence for any danger from ultrasound during pregnancy. See the entire
definition of Ultrasound
Vertebra: A vertebra is one of 33 bony segments that form the spinal column of
humans. There are 7 cervical, 12 thoracic, 5 lumbar, 5 sacral (fused into one sacrum
bone) and 4 coccygeal (fused into one coccyx bone). See the entire definition of
Vertebra
Vertebrae: The preferred plural of vertebra. (The alternate plural is vertebras.) See also:
Cervical vertebrae; Coccygeal vertebrae; Lumbar vertebrae; Sacral vertebrae; and
Thoracic vertebrae.
X-ray: 1. High-energy radiation with waves shorter than those of visible light. X-rays
possess the properties of penetrating most substances (to varying extents), of acting on
a photographic film or plate (permitting radiography), and of causing a fluorescent
screen to give off light (permitting fluoroscopy). In low doses X-rays are used for making
images that help to diagnose disease, and in high doses to treat cancer. Formerly called
a Roentgen ray. 2. An image obtained by means of X-rays. See the entire definition of
X-ray
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