If you have severe neck pain that isn’t responding to non-operative treatments like medication or physical therapy, it may be time to discuss surgery with your doctor. Cervical artificial disc replacement should be part of your conversation.
Richard D. Guyer, MD, co-founder and fellowship director at the Texas Back Institute, co-Director of the Center for Disc Replacement, and an associate clinical professor of orthopaedics at the University of Texas Southwestern, is an expert on cervical artificial discs and dedicates his practice to the technique. See how he might treat a potential candidate for cervical artificial disc replacement in this real-life patient example.
Margaret, a 47-year-old mother of 3 boys was diagnosed with a mild disc herniation at the C5-C6 level of her cervical spine. She’s tried several non-operative treatments and wants to avoid surgery. However, Margaret is beginning to rethink her options because of worsening neck pain that radiates down into her arm, causing occasional numbness and tingling sensations. Her doctor recommended spinal fusion, but Margaret is hesitant. She wants to know more about cervical disc replacement, and if she may be a candidate.
Dr. Guyer: In Margaret’s case, she is only 47-years-old—so, ideally, we’d like to preserve the motion in her neck with a disc replacement rather than take it away with a fusion.
Initially, spinal fusion and artificial disc replacement both have the same results. The difference between these procedures shows up when you look at the long-term results. The data shows that 7-10 years after surgery, patients who have artificial disc replacement have a 3-4 times lower risk of having to undergo a second surgery compared to patients who have spinal fusion. Spinal fusion causes more stress and strain at the adjacent levels of the spine, which increases the risk for a second surgery down the line.
Cervical artificial disc replacement delivers excellent pain relief, specifically for arm pain. Many patients report complete resolution of arm pain immediately following the procedure. Also, functional activities are markedly improved within 6 weeks, and patients continue to do well 7 to 10 years following their procedure.
Dr. Guyer: A spinal fusion is recommended when there’s a severe collapse of the disc or when large bony spurs are present that require too much removal of bone for an artificial disc to be safely implanted.
Q: With a patient like Margaret, what do you typically find during a physical and neurological examination?
Dr. Guyer: She has a herniation at C5-C6, so I’d expect her to complain of neck, shoulder, and arm pain that radiates down into her thumb. She typically would have a provocative Spurling’s maneuver which would reproduce the pain that radiates down Margaret’s arm. She also may have an absent biceps reflex and numbness of the thumb.
Sometimes, patients like Margaret have pain at base of their neck—this is where the C5-C6 nerve roots exit the spine. They also often have tenderness in and around the shoulder blade.
Q: What imaging tests would you order for Margaret?
Dr. Guyer: Typically, we would order plain x-rays, bending films (forward and backward, also termed flexion and extension) and MRI within 6 months.
Dr. Guyer: There are several differences between artificial discs. Some discs are more stable than others. A more stable disc may be preferred for someone who has hypermobility in their neck and requires a disc with more constraint. Discs are made from different materials, such as metal with polyethylene, metal with metal, and polyurethane. Also, some of the newer discs allow for some compression, which is designed to more closely simulate a human disc.
The artificial discs are tested in a laboratory setting and found to last the equivalent of 40 years.
Q: Is the surgery performed open or minimally invasively?
Dr. Guyer: Yes, this is a minimally invasive procedure. In Margaret’s case, she would require a single-level implantation, which typically utilizes a 2.5-cm incision made in a skin crease or parallel to the crease. The procedure is performed anteriorly—through the front of the neck. I only cut through the skin and a thin layer of muscle under the skin and then bluntly dissect so that the normal anatomy is not disturbed. This means less pain after surgery and shorter recovery times.
Q: Do all spine surgeons perform disc replacement surgery in the neck? How should a patient select a surgeon?
Dr. Guyer: Not all surgeons do disc replacement, so a patient needs to do their research to find surgeons who are very experienced in disc replacements.
At Texas Back Institute, our center was the first to do disc replacement. We’ve offered this procedure since March of 2000, and I continue to dedicate my practice to it.
Q: How important is a surgeon’s personal surgical outcomes?
Dr. Guyer: The more procedures a surgeon does, the better the outcomes. This goes for any surgical procedure, not just cervical artificial disc replacement.
My two partners and I have cumulatively done more than 2,000 disc replacement surgeries. Find a surgeon with vast experience, and you can expect better outcomes.
Q: In your hands, what might Margaret expect before and after cervical disc replacement surgery?
Dr. Guyer: Before surgery, Margaret is going to be symptomatic—she’ll have neck and arm pain, which will affect her quality of life. After surgery, I expect her to wake up with complete relief of her arm pain. Cervical artificial disc surgery has a 95% chance of resolving arm pain.
Her neurological symptoms—the numbness and weakness—may be slower to respond after surgery. The vast majority of patients will see their nerve function restored after cervical artificial disc replacement, but it could take up to year. It also depends on how long the patient experienced the nerve-related symptoms before spine surgery.