The cervical spine (neck) is composed of seven vertebrae. There are discs in-between the vertebrae, which act as cushions or shock absorbers between the vertebrae of the neck. Discs can become damaged either through trauma or degeneration, and cause pain, numbness, weakness, and/or other symptoms, a condition typically referred to as degenerative disc disease, a sub-group of which includes cervical disc herniations. This means the disc becomes compressed, frayed, and/or herniates into the central spinal cord or on the individual nerve roots that exit from the spinal canal at each vertebral level.
The standard initial treatment for the symptomatic cervical disease involves conservative (non-surgical) methods, which may include anti-inflammatory medications, physical therapy, cold/heat therapy, and occasional spinal injection procedures. Above 90% of patients experience pain relief within 6-12 weeks. If the symptoms continue for more than this period, surgical treatment can be considered.
One such procedure is cervical disk replacement surgery, also known as total disc arthroplasty, which involves removing a diseased cervical disc and replacing it with an artificial disc. It differs from traditional cervical disc surgery as it does not involve fusion of the upper and lower vertebrae once the diseased disc is removed from between them. Instead, an artificial disc is inserted between the vertebrae. The artificial disc is typically composed of two metallic surfaces, one of which is attached to the upper and the other to the lower vertebra at the affected disc level. These metal implants can either slide on each other directly or can be separated by a piece of medical grade plastic. The artificial disc acts like a normal disc, providing motion while acting as a shock absorber in the spine (unlike a fusion, which eliminates both motion and shock absorption in the fused segment of the spine). The artificial disc can be secured in place with screws.
Symptoms of degenerative disc disease
Degenerative disc disease (DDD) is a condition that can occur in the neck or low back and cause significant pain. As we age, the discs typically dehydrate and become more brittle; this happens to most people by age of 60 years. Some people have more symptoms from cervical disc degeneration than others.
Symptoms may include:
- Neck pain and stiffness.
- Pain that radiates to your shoulders/ arms.
- Weakness in shoulders, arms, hands, or legs.
- “Pins and needles” or numbness in your arms.
Reasons for the procedure
There are several reasons to perform artificial disc replacement surgery in patients suffering from DDD:
- Severe pain for prolonged period (typically six months).
- Patient has undergone non-surgical treatment and hasn’t received any relief from the above-mentioned symptoms.
- Restore spine to normal state.
- Rapid recovery compared to spine fusion surgery.
Risks of the procedure
As with any surgical procedure, complications can occur. Some complications may include, but are not limited to, the following:
- Implants bending, breaking, loosening, or moving.
- Nerve injury or paralysis.
- Spinal fluid leak.
- Voice change.
- Difficulty breathing and swallowing.
- Need for further surgery.
There may be other risks, depending on your specific medical condition. Be sure to discuss any concerns with your surgeon before the procedure. You should also discuss the risks and benefits of disc replacement compared to traditional spinal fusion surgeries with your surgeon.
Before the procedure
- Your doctor will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the surgery.
- You may be asked to sign a consent form that gives your permission to do the procedure. Read the form carefully and ask questions if something is not clear.
- In addition to a complete medical history, your doctor may perform a complete physical examination to ensure you are in good health before undergoing the procedure. You may undergo blood tests or other diagnostic tests.
- Notify your doctor if you are sensitive to or are allergic to any medications, latex, tape, and anaesthetic agents (local and general).
- Notify your doctor of all medications (prescribed and over-the-counter) and herbal supplements that you are taking.
- Notify your doctor if you have a history of bleeding disorders or if you are taking any anticoagulant (blood-thinning) medications, aspirin, or other medications that affect blood clotting. It may be necessary for you to stop these medications prior to the procedure.
- You will be taught special ways to do everyday things after surgery to protect the spine. This includes learning how to move properly, changing from one position to another, and sitting, standing, and walking.
- If you smoke, you will be asked to stop it. People who have spine surgery and keep smoking do not heal as well. Ask the doctor for help.
- Let the doctor know right away if you have any cold, flu, fever, herpes breakout, or other illness before the surgery.
- On the day of the surgery, you will likely be asked not to eat or drink 6 – 12 hours before the procedure.
- Take any medicines the doctor told you with a small sip of water.
During the procedure
Disc replacement surgery requires a stay in the hospital. Procedures may vary depending on your condition and your doctor’s practices.
Generally, the surgery follows this process:
- You will be asked to remove clothing and given a gown to wear.
- An intravenous (IV) line will be started in your arm or hand. Additional catheters may be inserted to monitor the status of your heart and blood pressure, as well as for obtaining blood samples.
- If there is excessive hair at the surgical site, it may be clipped off.
- A catheter will be inserted into your bladder.
- The surgery will be performed while you are asleep under general anaesthesia. The anesthesiologist will continuously monitor your heart rate, blood pressure, breathing, and blood oxygen level during the surgery.
- The area of your neck where the incision will be cleansed with an antiseptic solution.
- A one- to two-inch (3-5 cm) horizontal incision is made on the side or front of your neck.
- The vital parts of the neck are carefully moved aside for the surgeon to be able to see the vertebrae and the cervical disc.
- The diseased cervical disc is exposed and removed. Magnification with a microscope or surgical magnifying glasses may be used to facilitate complete removal of the disc and decompression of the nerves.
- The artificial disc is carefully placed into the empty position between the vertebrae.
- The incision is closed using stitches under the skin. The skin is then carefully closed.
- A small dressing is applied over the incision.
- Your surgeon may place a drain into the wound, which is typically removed on the day following the procedure.
- A rigid or soft cervical collar may be put on your neck for immobilization.
After the procedure
After the surgery, you will be taken to the recovery room for observation. Once your blood pressure, pulse, and breathing are stable and you are alert, you may be taken to the intensive care unit (ICU) or your hospital room. You will need to stay in the hospital for about 2-3 days after surgery.
- Intravenous fluids may be continued until you can drink fluids well by mouth.
- Once you are able to drink normally, you will be able to start eating your normal diet.
- Pain after the procedure is usually limited and improves markedly within two to three days. You’ll continue to take pain medication if you need it.
- Your dressing will be checked and changed if needed.
- Nurses will help you to get out of bed and go to the bathroom.
- You may have to continue wearing the cervical collar in the hospital.
- Nerve symptoms such as pain, numbness, and weakness are often dramatically improved within hours of the surgery, but in some cases can take weeks or even months to recover.
- X-rays are obtained following surgery to confirm proper positioning and functioning of the artificial disc placed between your vertebrae.
- You will be encouraged to get out of bed and move around as soon as you are able to.
Aftercare at home
The length and type of activity restrictions following surgery are much less with disc replacement. However, before you are discharged from the hospital, your doctor and other members of the hospital staff will give you additional self-care instructions for you to follow at home.
- Do not lift heavy weights.
- You can shower but should keep the incision area covered with a bandage and tape, and try to avoid the water from hitting directly over the surgical area. Talk to your doctor for instructions.
- You may return to light recreational sports not before three months after surgery.
- Driving is recommended after 7-14 days of surgery. Do not drive when you are taking pain-relieving medicines.
- You should inform your doctor if you have difficulty swallowing or any other discomfort related to surgery.
- There are no permanent restrictions after 6 months of the date of surgery.
You should visit your doctor for a follow-up visit approximately 12-14 days after surgery. The incision will be inspected. Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.
Most patients are capable of returning to light work within a week or two of surgery and to full duty six weeks following the procedure.