Cervical Disc Replacement

Overview

Non-spinal diseases such as rotator cuff tears, tennis elbow, and carpal tunnel syndrome can all cause or contribute to arm and neck pain. The problem for certain people is frequently with the spinal column and nerves in the neck, known as the cervical spine. A ruptured or bulging disc that pushes on these spinal nerves is one of the most prevalent ailments. Previously, the sole treatment was to remove the cervical disc and fuse the vertebrae in the neck together. This was frequently done with bone from the "hip" or the iliac crest. This required patients to have an additional procedure, which was frequently more painful than the neck surgery.

Several prosthetic cervical discs, on the other hand, have been created and are now accessible as a surgical alternative to address cervical disc abnormalities that cause persistent neck pain and other symptoms such as arm discomfort or paralysis.

What is Cervical Disc Replacement?

From an engineering standpoint, the natural cervical intervertebral disc is a unique mechanical structure. It can withstand a huge compressive force while yet allowing for an amazing range of motion between the bones in the neck. It is difficult to replicate the natural disc's form and function with an artificial disc.

When treating cervical pathology that has not responded to conservative therapy, spine surgeons and patients are faced with a number of surgical choices. Well-designed mid- and long-term studies have supported anterior cervical discectomy and fusion (ACDF), posterior laminoforaminotomy, laminoplasty, and laminectomy with fusion. These surgical techniques are effective in relieving cervical radiculopathy and stopping the progression of cervical myelopathy, but they each have risks that can lead to recurrence, adjacent segment degeneration (ASD), or the need for revision surgery.

In the last two decades, modern technology and materials have made cervical disc replacement viable, and for many patients, preferable to fusion. Modern spinal disc replacement devices, like hip and knee joint replacement, are comprised of high-quality metals and plastic and aid in the preservation of the neck's natural mobility. The largest research on cervical disc replacements included thousands of patients who had over seven years of clinical follow-up.

Patient indications

Patients with underlying cervical degenerative disc degeneration with the clinical manifestation of cervical radiculopathy or myelopathy who have not responded to conservative therapy are now candidates for Cervical Disc Replacement (CDR). Patients frequently arrive with cervical disc pathology in association with spondylosis or foraminal stenosis, complicating the choice. Patients lacking dynamic instability (>3.5 mm translation on flexion-extension lateral radiographs) or circumferential spinal cord compression (as found in patients with severe spondylosis or widespread ossification of the posterior longitudinal ligament) are suitable candidates for CDR.

Patients with significant axial neck discomfort owing to facet arthropathy should be advised carefully before undergoing CDR, since these symptoms may not improve, and when severe arthropathy is leading to instability, CDR may not be the best surgical option.

Some publications propose a disc height of more than 3 mm for proper disc space access and removal. Placing a large implant into a collapsed disc space may result in excessive stresses being applied to the facet joints, exacerbating axial neck discomfort.

Patients with a kyphotic deformity of more than 15° should be addressed with caution, since severe kyphotic deformity is often associated with posterior spinal disease (ligamentum flavum hypertrophy, facet capsule thickening, etc.). Because the purpose of CDR is to conserve motion rather than reproduce motion, awareness of the cervical spinal region in issue should be included during preoperative planning.

Active infection, known malignancy, inflammatory spondyloarthropathy, allergy to implant materials, and metabolic bone disease (osteoporosis, renal osteodystrophy, etc.) are all contraindications to CDR. Osteoporosis is a contraindication for CDR because it increases the risk of implant subsidence and migration. Other approach-related problems, such as patients who have previously undergone anterior neck surgery, should be evaluated thoroughly by an otolaryngologist to check vocal cord integrity and minimize iatrogenic nerve damage.

Preparing for Cervical Disc Replacement Surgery

Sign permission documents and present your medical history (allergies, medications/vitamins, bleeding history, anesthetic responses, and past operations) in the office. Inform the surgeon about all drugs you are taking (prescription, over-the-counter, and herbal supplements). Preoperative testing (blood tests, EKG) may be required several days before surgery. Consult your primary care physician about discontinuing certain drugs and ensuring you are surgically cleared.

7 days before surgery, discontinue all nonsteroidal anti-inflammatory medications (ibuprofen, naproxen, etc.) and blood thinners (Coumadin, aspirin, Plavix, etc.). To avoid bleeding and healing issues, stop using nicotine and drinking alcohol one week before and two weeks after surgery.

Before surgery, you may be requested to cleanse your skin with Hibiclens (CHG) or Dial soap. It eliminates microorganisms and lowers the risk of surgery site infections. (Do not get CHG in your eyes, ears, nose, or genital regions.)

Stop smoking

The most essential thing you can do to prepare for surgery is to quit smoking. Cigarettes, e-cigarettes, cigars, pipes, chewing tobacco, and snuff / dip are all included. Nicotine reduces circulation, delays wound healing, and increases infection risk. Consult your doctor about quitting methods.

Morning of surgery
- Before surgery, don't eat or drink anything after midnight (unless the hospital tells you otherwise). Allowable medications may be taken with a little sip of water.
- Shower using antibacterial soap or Hibiclens.
- Dress in freshly washed, loose-fitting clothing.
- Wear flat-heeled shoes with closed backs.
- Remove makeup, hairpins, contacts, body piercings, jewelry, and nail polish.
- Bring a list of medications with dosages and the times of day taken.
- Bring a list of allergies to medication or foods.

Arrive at the hospital early enough to complete paperwork and health checks before your procedure. An anesthesiologist will discuss the effects and dangers of anesthesia with you.

How is Cervical Disc Replacement Performed?

Using sophisticated equipment, the target cervical disc is securely reached by an incision of about an inch and a half or less. The disc is viewed and removed using a high-powered surgical microscope, and nerves are freed of any bone spurs or herniated disc debris that may be causing pain or weakness (decompression). In contrast to cervical fusion surgery, the patient is not required to wear a neck brace until fusion is visible on x-ray, and mobility is encouraged.

The benefits of cervical disc replacement vs fusion have been extensively researched. For properly chosen patients, CDR:

Maintains range of motion
Has a lower rate of additional surgery
Less wear and tear at adjacent spinal levels

Even a single level fusion (for example, C4-C5) in the cervical spine places stress on the surrounding levels above and below the fusion. The nearby levels in the neck are more prone to stress and wear down faster.

What happens after surgery?

You will be revived at the recovery area. Your blood pressure, heart rate, and breathing rate will all be measured. Any discomfort will be alleviated. You can begin mild movement after you are awake (sitting in a chair, walking). The majority of patients are discharged the same day. If you have trouble breathing or have unstable blood pressure, you may need to remain overnight.

Some people may have hoarseness, painful throat, or trouble swallowing. These symptoms normally go away within 1 to 4 weeks. Follow the surgeon's home-care recommendations for the next two weeks or until your follow-up appointment. In general, you may anticipate:

Restrictions

Avoid bending or twisting your back.
Don't lift anything heavier than 5 pounds.
No strenuous activity including housework, yard work, or sex.
Don't drive the first 2-3 days or while taking pain medicines or muscle relaxers.
Don't drink alcohol. It thins the blood and increases the risk of bleeding. Also, don't mix alcohol with pain medicines.

Incision Care

You may shower the day after surgery if Dermabond skin glue covers your wound. Every day, gently cleanse the area with soap and water. Avoid rubbing or picking at the adhesive. Allow to air dry.
Showering is permitted two days after surgery if you have steri-strips or sutures. Every day, gently cleanse the area with soap and water. Allow to air dry.
Cover the wound with a dry gauze bandage if there is any drainage. Call the office if drainage soaks through two or more bandages in a single day.
Don't soak the incision in a bath or pool.
Don't apply lotion or ointment on the incision.
Dress in clean clothes after each shower. Sleep with clean bed linens. No pets in the bed until your incision heals.
Steri-strips and stitches are removed at your follow-up appointment.

Medications

Take pain relievers as prescribed by your surgeon. As your discomfort lessens, reduce the dosage and frequency. Don't take the pain reliever if you don't need it.
Constipation can be caused by narcotics. Drink plenty of water and consume meals high in fiber. Stool softeners and laxatives can aid with bowel movement. Over-the-counter medications include Colace, Dulcolax, and Miralax.
If the unpleasant constipation does not improve, see your doctor about additional options.
For 6 weeks, your surgeon may prescribe nonsteroidal anti-inflammatory medication to prevent bone formation around the disc device.

Managing pain

Ice your incision 3-4 times per day for 15-20 minutes to reduce pain and swelling.
Don't sit or lie in one position longer than an hour unless you are sleeping. Stiffness leads to more pain.

Activity

Every 3-4 hours, get up and walk for 5-10 minutes. Increase your walking time gradually as you are able.
You are urged to move your neck lightly as tolerated.
For a few days, you may experience a painful throat or trouble swallowing. Consume a modest diet of soft foods in small portions. Return to your regular diet as tolerated.

When to Call Your Doctor?

Fever over 101.5 (not relieved by Tylenol)
Unrelieved nausea or vomiting
Severe, unrelieved pain
Unable to urinate 6-8 hours after surgery despite having a full bladder
Signs of incision infection
Rash or itching at the incision. It may be an allergy to Dermabond skin glue.
Swelling and tenderness in the calf of one leg (sign of a blood clot)
New onset of tingling, numbness, or weakness in the arms or legs
Dizziness, confusion, nausea, or excessive sleepiness

How Long Will It Take Me to Recover?

Your surgeon will develop a post-operative recovery plan that will allow you to resume your usual activity level as soon as feasible. Your hospital stay will be determined by your treatment and physical state. You should be up and walking by the end of the first day after surgery. Your return to work will be determined by how well your body heals and the sort of employment/activity level you intend to resume.

Working closely with your spinal surgeon to find the best recovery program for you, and following his or her recommendations carefully, will help you recuperate faster.

What are the results?

Discuss the most recent results of the exact disc device that your surgeon advises.

According to studies, cervical artificial disc replacement (ADR) relieves arm discomfort in more than 70% of patients. Cervical ADR has demonstrated results that are at least similar to ACDF in terms of alleviating neck pain, arm discomfort, patient function, and satisfaction, with no increase in surgical complications. These findings are based on 5 to 10 years of follow-up in FDA-approved trials.

When compared to ACDF, the total rate of adjacent segment illness with cervical ADR is 14 percent (7-23 %) at 10 years. The occurrence of bone overgrowth (heterotopic ossification) varies greatly across artificial disc devices.

Risks of Cervical Disc Replacement

No surgery is without danger. Bleeding, infection, blood clots (deep vein thrombosis), and anesthetic responses are all dangers of every operation. Hoarseness and swallowing difficulty are two specific hazards associated with artificial disc replacement. Temporary hoarseness can occur in various instances. During surgery, the recurrent laryngeal nerve, which controls the voice cords, may be inflamed. This nerve may take many months to heal. Hoarseness and swallowing issues may continue in rare situations (less than 1/250) and require additional treatment with an ear, nose, and throat specialist.

Overgrowth of the bones (heterotopic ossification). Bone growth may begin around the artificial disc device. This might show up on follow-up x-rays months or years following surgery. On a 5-point scale, bone growth is assessed. This may decrease range of motion or create a bridge across the device, resulting in unwanted fusion. Nonsteroidal anti-inflammatory medicines (NSAIDs) used for 6 weeks following surgery have been demonstrated to reduce the likelihood of ossification.

Device relocation. In rare cases, the endplates and central core of the artificial disc may shift out of place. If this occurs, a second operation to repair or replace the device may be required.

Metal hypersensitivity. There have been instances of artificial discs with metal-on-metal bearings emitting metal ions, which may react with adjacent tissues, causing discomfort or implant failure. Additionally, some people may be allergic to the nickel, chromium, or cobalt in the metal device.

Fracture of the vertebrae. A vertebra may fracture during or after surgery in rare cases. The fracture may be able to heal if the neck is immobilized with a brace. In the event that a second operation is necessary, the artificial disc is removed and a fusion is done.

Nerve injury or chronic discomfort Any spine operation has the potential of causing nerve or spinal cord damage. Numbness or even paralysis might result from damage. The most common reason of prolonged pain, however, is nerve damage caused by the disc herniation itself. Some disc herniations can permanently destroy a nerve, rendering it inoperable. The compressed nerve, like carpet beneath furniture, does not spring back. In such circumstances, spinal cord stimulation or other therapies may be beneficial.

Cervical Disc Replacement vs ACDF: Which Should You Choose?

You have therapy choices if you experience neck discomfort or radiating pain caused by cervical spine injury. You do not have to live in agony, but you must decide which operation is best for you. Artificial disc replacement and anterior cervical discectomy and fusion (ACDF) are two of the most successful cervical spine operations

For many years, ACDF has been the gold standard in cervical spine surgery. It is risk-free, effective, simple to execute, and simple to recover from. ACDF surgery is divided into two sections. First, the injured or herniated cervical disc is completely removed (discectomy). The damaged vertebra is then covered with a bone graft to stimulate it to grow into the backbone above or below it (fusion). This prevents possibly painful vertebral movement.

Both of these treatments are successful in treating herniated discs, degenerative disc disease, and other disorders of the cervical spine. Patients will collaborate with their physicians to choose which surgery is best for their specific condition and circumstance.

ACDF Advantages

ACDF can be preferable for many reasons, including:

- ACDF is established: ACDF operations have been performed by surgeons for decades. Its efficacy and safety profile are both well-known.
- ACDF can treat more people: ACDF may be appropriate for those who have undergone prior neck surgery, have injured vertebrae, or have facet joint degeneration.
- ACDF is probably covered by insurance: This is due to the fact that ACDF is a well-established treatment with a lengthy track record of success.
- ACDF is less complicated than a cervical disc replacement: The artificial disc must be precisely sized and inserted in a disc replacement. ACDF does not have such a criterion.

When comparing these two operations, there is no "better," only what is best for you and your scenario. Both methods are safe and successful. It is up to you and your surgeon to decide which one to use.

Conclusion

Cervical disc replacement (CDR) was devised to retain mobility after a decompression treatment while reducing many problems associated with fusion and posterior cervical spine surgeries. Though cervical fusion and posterior foraminotomy have been thoroughly described in the literature, there are substantial rates of mid and long-term problems. CDR has also been linked to a number of surgical problems and issues, despite the fact that advances in implant design have led to a rise in usage. Several devices are now available, with varying materials, designs, and outputs.