Cervical Disc Replacement
In order to understand the FDA approved total cervical disc replacement, it’s important to first be familiar with the cervical spine and degenerative disc disease. Below is a short video that explains the cervical disc replacement procedure.
The Cervical Spine
A healthy cervical spine is made up of seven bones (vertebrae) that stack one on top of the other. Between each of these vertebrae are cushions (cervical discs) that act like shock absorbers for the spine. The vertebrae provide a protective tunnel for the spinal cord to pass through. The spinal cord also sends out spinal nerves through openings between the cervical vertebrae. These nerves supply your arms with sensation and movement.
Degenerative Disc Disease
Degenerative disc disease is a process that occurs as we age, although an injury, such as a fall or motor vehicle accident, may also begin the degenerative process.
As discs degenerate, they lose fluid which makes them less flexible and less effective in absorbing shock. They also become thinner, thus narrowing the space between the vertebrae. The spine then becomes less stable and produces bony growths called bone spurs (osteophytes). Bone spurs can also be produced when the cartilage that cushions joints breaks down, causing inflammation (osteoarthritis).
Herniated, bulging or ruptured discs can also occur with degenerative disc disease. As discs age, tiny cracks can appear in the outer layer of the disc. Through these cracks, the jellylike material inside the disc may be forced out. This causes the disc to bulge or break open (rupture).
Any of the above conditions can cause loss of feeling, loss of movement, pain, weakness or tingling down the arm and possibly into the hands. Diagnosis usually involves a doctor’s examination and a CT, MRI or X-ray to identify the cause and extent of the problem.
Conservative treatment for degenerative disc disease may include:
- activity modification
- anti-inflammatory medicines (NSAIDs)
- physical therapy or chiropractic treatment
- epidural steroid injections or radio frequency ablation/rhizotomy
If six weeks of conservative treatments fail, or if symptoms worsen despite treatment, then cervical disc replacement surgery may be an option.
Who is Eligible for Cervical TDR?
When conservative treatment fails, a cervical disc replacement surgery is recommended for adults, ages 21-67, who have one or two damaged cervical discs (C3-C7) next to each other, weakness in their arms, or symptoms that affect daily activities.
Who is Not Eligible for Cervical TDR?
Patients with any of the following conditions are not eligible for Cervical TDR: isolated axial neck pain, ankylosing spondylitis or pregnancy, rheumatoid arthritis, autoimmune disease, severe arthritis, spinal infection, metal allergy to components of the prosthesis, severe osteoporosis/osteopenia, active malignancy, metabolic bone disease, trauma, instability, three or more discs requiring treatment, insulin dependent diabetes mellitus, HIV, hepatitis B/C, morbid obesity.
What are the Advantages of Cervical TDR?
The traditional spine fusion and Cervical TDR are both surgical approaches to decompress the spinal cord and nerve roots. A spine fusion removes the diseased disc then fuses the cervical vertebrae above and below the disc. This increases the chance of developing degenerative disc disease or a herniated disc at sites above and below the surgery.
With Cervical TDR, the discs are not fused. This creates less stress on the remaining vertebrae and maintains a more natural range of motion at the replacement site. In addition, with Cervical TDR there is less need for bracing, more natural range of motion and less need for future surgeries. Finally, with only a three to four-week recovery period, patients to return to work more quickly.
What does Cervical TDR Surgery Involve?
With Cervical TDR surgery, a one- to two-inch incision (surgical cut) is made on the front of your neck. The important structures of the neck are carefully moved to the side to allow the surgeon to see the bones of the vertebrae and the cervical disc.
The cervical disc that is being replaced is removed. The artificial disc is placed into the empty disc space. The incision is closed using absorbable sutures (stitches) under the skin. The skin is then carefully closed with sutures that minimize any scarring. A small dressing is applied over the incision, and you will be taken to the recovery area.
How Long Does a Cervical TDR Last?
Since Cervical TDR has only been around for approximately 10-15 years, we don’t have enough long-term data to answer this correctly. However, ten-year studies have produced very good literature that Cervical TDR is a safe and reliable procedure that has very good results.
Glossary of Terms
- Artificial Disc – A medical implant used to replace a worn out disc.
- Cervical Spine – Includes the first seven vertebrae of the spinal column (neck).
- Degeneration – Deterioration of tissue, which may include loss of function.
- Disc – Soft pad of cartilage between each vertebrae of the spine. The discs hold the vertebrae apart, act as cushions, and allow the vertebrae to move.
- Food and Drug Administration (FDA) – Part of the United States government. The FDA makes rules for companies that protect the patients who need medicine or medical implants. The FDA also helps decide which and how implants can be used.
- Fusion – When two bones grow together stopping movement.
- Implant – A device that is put in the body to fix or take the place of a damaged body part.
- Incision – A cut in the skin made during surgery.
- MRI – Magnetic Resonance Imaging (MRI) is a radiographic procedure that uses magnets to create cross-sectional images (like slices) of the body.
- Nerves – Fibers that move messages to and from the brain. Nerves control feeling and movement. Nerves connect the skin, organs, and muscles through the spinal cord to the brain.
- Nucleus Pulposus – The soft center of a spinal disc.
- Physical Therapy (PT) – Using exercise and massage to help regain movement.
- Spinal Cord – Bundle of spinal nerves. The spinal cord starts at the bottom of the brain and runs to the lower back. The spinal cord moves messages between the brain and the body.
- Spine – The 33 vertebrae starting under the skull and ending in the small of the back. Grouped into three sections: cervical (upper), thoracic (middle), and lumbar (lower). Protects the spinal cord and provides body support.
- Surgery – An operation on the body to fix, remove, or replace diseased or injured tissue.
- Vertebrae – The bones that form the spinal column with a hole for the spinal cord to pass through.