Anterior Cervical Discectomy and Fusion – Before and after
Ross Hauser, MD | Caring Medical Regenerative Medicine Clinics, Fort Myers, Florida
David Woznica, MD | Caring Medical Regenerative Medicine Clinics, Oak Park, Illinois
Danielle R. Steilen-Matias, MMS, PA-C | Caring Medical Regenerative Medicine Clinics, Oak Park, Illinois
Anterior Cervical Discectomy and Fusion – neck pain before and after
Many people come to Caring Medical because they have issues with cervical neck instability and cervical radicular pain that radiates into their arms and they are looking for a realistic treatment option to their Anterior Cervical Discectomy and Fusion recommendation. In separate articles we discuss Cervical neck instability, and, Atlantoaxial instability, and how these conditions can send you to Anterior Cervical Discectomy and Fusion. This article will focus more on the research surrounding the surgical outcome of this procedure and realistic options for avoiding the surgery. Further, in this article, we will explore our non-surgical regenerative medicine options to repair and stabilize the cervical spine.
- NOTE: Many people benefit from Anterior Cervical Discectomy and Fusion, especially people who have neck injuries from sport or accident where bones are fractured or in cases of significantly advanced degenerative disease where there is truly no other way to restore arm and hand function. This article will focus on “elective surgery,” meaning that you chose to have a surgery that is not addressing an urgent health crisis. It is typically these “elective,” surgeries that bring patients to our clinics with post-surgical pain and challenges.
In this article we are going to cover research from the surgical community addressing these patient concerns:
- If you do not have surgery are you at risk for worsening degenerative disc disease?
- Is your Neck MRI showing a true picture of your problem?
- Risks and complications from the surgery.
- Was the surgery as successful as the surgeon thinks it was?
- How much neck motion will I lose.
The realistic expectation of surgery from a neurosurgeons point of view:
In the Journal of neurosurgery. Spine, (1) August 2019, neurosurgeons from some of the leading neurological surgery departments in the nation published these findings on whether or not patients were truly satisfied with their surgical outcomes following anterior cervical discectomy and fusion (ACDF).
- A total of 4148 patients (average age 54 years, 48% males) with complete 12-month North American Spine Society satisfaction data (a scoring system) were analyzed.
- Sixty-seven percent of patients answered that “surgery met their expectations”
- 20% reported that they “did not improve as much as they had hoped but they would undergo the same operation for the same results”
- The findings of the present analysis further reinforce the role of preoperative discussion with patients on setting treatment goals and realistic expectations.
Comment: We should note that:
- 67% of patient had their expectations met. They had a realistic expectation of what the surgery could do.
- 20% of the patients did not have their expectations met but after surgery found enough satisfaction that they would do it again.
- 13% had less than desirable results.
Now that we have examined the realistic expectation of surgery, let’s look at what people who have been told that they need the surgery are saying.
Surgery because your neck will get worse? Researchers suggest that for many people cervical degeneration does not move that quickly that surgery is urgently needed.
For some people, cervical neck surgery may be urgently needed. Research suggests that not everyone is in that situation.
A study in the medical journal Spine (2) sought to determine whether cervical degenerative spondylolisthesis is a rapidly degenerating problem and a high-risk threat to patients or is it a more slowly degenerating disease.
Let’s look at the patients of this study:
- 27 patients with cervical degenerative spondylolisthesis
- The average age of the patient at the start of the study period was 59.0 years old. The youngest patient was 50 and the oldest was 83 years old.
Their cervical spine problems:
- Eleven patients had cervical spondylolisthesis at C4-C5
- Nine at C3-C4
- Six at C5-C6
- One at C2-C3.
- Of the 27 patients, 11 said they had NO SYMPTOMS
- Eight had cervicalgia (diagnosis of neck pain)
- Seven had radiculopathy
- One had myelopathy (spinal cord compression)
The patient’s history of cervical degenerative anterolisthesis and retrolisthesis seemed to be stable for 2 years to nearly 8 years
How much slippage?
- At the onset of the study:
- 3 of 6 patients diagnosed with anterolisthesis had translation (slippage) of more than 2 mm
- 7 of 21 patients with retrolisthesis had translation of more than 2 mm
Upwards of 8 years later how much worse were these patients problems?
- At a minimum of 24 months later (and an average of 3 years and 3 months later with a maximum range of seven years and 8 months,) the patient’s history of cervical degenerative anterolisthesis and retrolisthesis seemed to be stable during 2 years to nearly 8 years. Although those with retrolisthesis seem to have a higher propensity to increase their subluxation, none experienced dislocation or neurological injury.
The suggestion is that some people will experience a very slow degeneration of their cervical spine despite clear MRI documentation that their situation may warrant a surgical recommendation. This is usually where the problems begin, an MRI showing a need for surgery that may not be there.
“BUT I was told that if I did not have the surgery, I was at risk for becoming paralyzed”
In the many years of helping patients with neck problems, we have found that a main motivating factor to have the surgery was fear, fear of paralysis. This is typical when we ask patients “what finalized your decision to have the cervical fusion surgery?,” many respond, “I was told that I was at risk for becoming paralyzed. I cannot tell you how much that scared me. Now, looking back, maybe I rushed into the surgery and should have sought out more opinions.” In fact, some people do relate that they had two opinions, one surgeon who said surgery was not necessary and that the patient should continue conservative care therapy and one surgeon who talked about paralysis for a rapidly degenerating situation.
“I had pain after the surgery. I went back to the doctor and explained that I thought I would get more pain relief than I did from the surgery and now I seem to have new pain. The surgeon told me that the surgery that he performed was entirely successful. He fused the two vertebrae that needed to be fused, I just need more fused now.”
Some people come in after undergoing surgery, looking for ways to get off of the pain medications that they have been using. Other patients come in after successful surgery with new problems of TMJ or difficulty swallowing or dizziness and headaches. They are looking for help with those problems.
You may be getting a surgery because of an MRI reading that may not be accurate
We cannot begin to count the number of patients that we have seen over the many years who begin their conversation with us with “My MRI says I need the surgery.” What is now concerning some doctors is that doctors may be recommending a surgery based on an MRI which may not be entirely accurate.
- An MRI can show when there is an anatomical deformity that suggests surgery
- An MRI may be inconclusive that there is an anatomical deformity. These patients are being recommended to surgery anyway.
Look at this research from Yale University that was published in the Spine Journal (3)
“MRI findings play an important role in the management of patients with cervical spine conditions. For this reason, consistent descriptions of these findings are essential and physicians should be aware of the relative reliability of these findings. (Our) systematic study developed standardized grading criteria and nomenclature (a catalogue) for common clinically significant MRI findings in the cervical spine.
Even in this optimized research setting, we found significant ranges in agreement across these MRI findings. In the clinical setting, inter- and intra-rater agreements may be lower, and the range of agreements between findings may be greater. Physicians should be aware of inconsistencies inherent in the interpretation of cervical MRI findings and should be aware that some findings demonstrate lower agreement than others.”
- Simply, even in the “best-case scenario,” with the highest standards of interpretation applied, the MRI and interpretation may be wrong in presenting what is the true cause of the patient’s problems.
The MRI looks for a pinched nerve – if it finds one – a surgical recommendation can be made whether surgery is needed or not.
Anterior cervical discectomy and fusion (ACDF or sometimes anterior cervical decompression) is a cervical neck surgery that is recommended to patients that have been diagnosed with a pinched nerve in the neck that is causing pain, weakness, numbness and other symptoms of cervical radiculopathy.
- The discectomy removes a damaged disc identified as causing the patient’s problems. Once the disc is removed the fusion part of the surgery is performed.
- The fusion surgery’s goal is to successfully place a bone graft and/or an implant where the original disc was removed. The ultimate goal of the surgery is cervical stability and pain-free movement.
- The surgery can also address removing bony overgrowth or bone spurs that can pinch on the cervical neck nerves and be causing the problems of cervical radiculopathy. Typically numbness or weakness in the shoulders, arms, legs and upper neck region.
Understanding Anterior Cervical Discectomy and Fusion surgery, risks and complications during recovery.
Many people have great success with cervical fusion surgery. These are the people we do not see in our clinics because their surgeries went very well. The people seeking our help and the people we see in our clinics did not have such great success with their surgery.
At the beginning of this article, we discussed the two types of people that come to us looking for cervical neck pain. Those who are looking to avoid surgery and those who fell into the percentage of people who did not have the hopeful surgical outcomes of pain relief and function restored. Let’s briefly look at the journey some patients take after cervical neck fusion.
Anterior Cervical Discectomy and Fusion Recovery
There are many lifestyle changes following Anterior cervical discectomy and fusion.
For some, these lifestyle changes will be short-term, for others, the changes will be long-term and yet for others still these changes will last indefinitely or become non-ending in cases of complication and will require the need for revision neck surgery.
After the surgery:
- A March 2019 study (4) from the Ohio State University Wexner Medical Center suggests that if you suffer from metabolic syndrome, (obesity, high blood pressure, high cholesterol, diabetes), you will likely have to stay in the hospital a few days longer than usual.
- You may have to deal with problems of constipation and stressful bowel movements that may put a strain on your neck.
- You will likely need narcotic pain medications but will not be allowed to take NSAIDs such as Aspirin, Advil, Motrin, Aleve, Celebrex, etc., for fear that these medications will negatively impact the bone healing needed to complete the fusion. This recommendation can be anywhere from 3 to 6 months.
- Long-term alteration in your movements will be part of your recovery. This will include limited head movements, being able to lift common everyday objects over 5 pounds (like a gallon of milk or water), and regulating the amount of time you can sit.
- You may not be able to drive a car, have sex, or exercise for some time. (Please see our article Patients report problems with sexual function after cervical spine surgery)
The need for painkillers after surgery is a dangerous need
Here is a disturbing study from July 2019 published in the journal Pain research & management.(5)
- “Worldwide, 80% of patients who undergo surgery receive opioid analgesics as the fundamental agent for pain relief. However, the irrational use of opioids leads to excessive drug dependence and drug abuse, resulting in an increased mortality rate. . . “
- “Sensory dysfunction is a common symptom of neuropathic pain. Nerve injury as a result of surgical manipulation is a leading cause of neuropathic pain after surgery.”
In the April 2019 issue of Lancet, (6) researchers at the University of Pennsylvania and Harvard wrote that “excessive prescribing of opioids for pain treatment after surgery has been recognised as an important concern for public health and a potential contributor to patterns of opioid misuse and related harm.”
As mentioned above, when your cervical vertebrae are fused to limit cervical instability and related symptoms, the force and energy in your neck movements are transferred to the vertebrae below the fusion and above the fusion. This is why people suffer from the same symptom at different locations a year to 3 years later. This is why many people are sent back to surgery to fuse more segments and why many get the symptoms back and they can even be worse. Let’s explore research from some of the leading universities and research hospitals that support these findings.
Within 10 years, 1 in 4 patients can be at risk of clinical adjacent segment disease.
These are some of the things we hear from patients and people who email us with with questions who have to contemplate another procedure.
- My surgeon has recommended that I get another ACDF. This time the fusion will be below the first fusion I had at C5-C6. The new fusion will be at C7-C8. I am concerned that this will greatly limit my ability to move. I did not realize how much my neck movement would be after the first fusion.
- I had two ACDF fusions. My first surgery was more than 15 years ago at C6-C7. I just had C5-C6 fused. During the second surgery they discovered a lot of scar tissue from the first. I am having a lot of pain in my neck, shoulders, and back. I am on painkillers now.
- I had a very successful C4-C5 fusion. My problem now is C3. I have degenerative disc disease with rupture. Now they want to expand my fusion to C3-C5.
Doctors at the University of Alberta noted in the Canadian Journal of Neurological Sciences: “Cervical spine clinical adjacent segment pathology has a reported 3% annual incidence and 26% ten-year prevalence. Its pathophysiology remains controversial, whether due to mechanical stress of a fusion segment on adjacent levels or due to patient propensity to develop progressive degenerative change.”(7)
Simply, within 10 years, 1 in 4 patients are at risk of clinical adjacent segment disease because of unnatural stress and destructive forces being placed on the cervical spine.
Anterior cervical spondylosis surgery: a retrospective study with long-term follow-up found that fusion significantly and negatively alters the curve in the neck
In February 2018, orthopedic surgeons at Jinzhou Medical University in China wrote in the Journal of Orthopaedic Surgery and Research (8) about their investigation of the incidence and causes of non-fusion segment disease, both adjacent and non-adjacent to a fused segment, after anterior cervical fusion.
Here are the results of their investigation:
- 171 patients who had an anterior cervical decompression and fusion were followed clinically for more than 5 years.
- Of the 171 patients reviewed, 16 patients had non-fusion segment disease (9.36%), of which 12 had adjacent segment disease and 4 had non-adjacent segment disease.
- Postoperative cervical lordosis in the non-fusion segment disease group was significantly smaller than that of the disease-free group
- The incidences of disc degeneration in unfused segments were more severe in the non-fusion segment disease group than in the disease-free group
- The major factor affecting non-fusion segment disease is postoperative cervical lordosis followed by cervical disc degeneration.
The conclusion: “The incidence of symptomatic non-fusion segment disease after anterior cervical arthrodesis has multifactorial causes. Postoperative cervical lordosis and disc degeneration in non-fusion segments were major factors in the incidence of non-fusion segment disease.”
The second cervical spine fusion makes the cervical lordosis even worse
Surgery failed to restore or maintain the cervical lordosis
In May 2018, spinal surgeons operating in German and Egypt wrote in the medical journal Spine (9) about the problems of the second cervical neck surgery to fix the problems of cervical adjacent segment disease
Let’s focus on the fact pointed out by the researchers:
- “Anterior Cervical Discectomy and Fusion has provided a high rate of clinical success for the cervical degenerative disc disease; nevertheless, adjacent segment degeneration has been reported as a complication at the adjacent level secondary to the rigid fixation.”
We want to stress this point too: People benefit from this surgery, this article is for the people who don’t or maybe poor candidates for this type of surgery.
The learning point of this research is all about the curve of the neck
- 70 patients undergoing surgical treatment for adjacent segment disease after anterior cervical decompression and fusion.
- Surgery for adjacent segment disease was performed after an average period of 32 months from the primary Anterior Cervical Discectomy and Fusion.
- Adjacent segment disease occurred after single-level ACDF in 54% of cases, most commonly after C5/6 fusion (28%).
- Risk factors for adjacent segment disease were found to be preexisting radiological signs of degeneration at the primary surgery (74%) and bad sagittal profile (the curve was bad) after the primary anterior cervical decompression and fusion (90%).
CONCLUSION: Adjacent segment disease occurred predominantly in the middle cervical region (C4-6); especially in patients with preexisting evidence of radiological degeneration in the adjacent segment at the time of primary cervical fusion, notably when this surgery failed to restore or maintain the cervical lordosis.
The curve of the neck will be discussed further below
The surgery to fix the surgery. Revision and more fusion is no easy fix
The removal of implants secured through the endplates of adjacent vertebral bodies
Doctors at the Swedish Neuroscience Institute, Swedish Medical Center, in Seattle Washington led a study examining the failure patterns in standalone Anterior Cervical Discectomy and Fusion Implants. The study appeared in the September 2017 edition of the journal World Neurosurgery.(10)
Take home points:
- The goal of the study was to see how to help patients who suffered from Anterior cervical discectomy and fusion failure.
- Two-hundred eleven (211) patients were included in the study.
- There were 11 (5.2%) readmissions.
- There were 10 (4.74%) implant failures (five involving single-level surgery and five involving two-level surgery),
- There were seven cases of pseudoarthrosis (non-union fusion failure)
- Mechanisms of failure included:
- a C5 body fracture (the fusion cracked the vertabra).
- Fusion in a kyphotic alignment following graft subsidence, (the bone/fusion collapsed causing a “hunchback,” curve in the patient).
- and acute spondylolisthesis, the condition of “slipped disc” or “slipped vertebra.
- Revision surgery following standalone anterior cervical implants can be complex.
- Surgery from behind Posterior (behind). Posterior cervical fusion remains a valuable approach to avoid possible vertebral body fracture and loss of fusion area associated with the removal of implants secured through the endplates of adjacent vertebral bodies.
Patients with cervical instability are getting surgeries that cause more instability and deformity
Doctors at South Korea’s Pusan National University published this research in the Journal of Korean Neurosurgical Society.(11)
What these researchers are warning is that the cervical spine and its attachment to the thoracic spine are more unstable than thought. This presents a paradox, patients with cervical instability are getting surgeries that cause more instability and deformity. Here is the result of this research:
The quick points:
- Thoracic spine involvement: Prior to Anterior cervical discectomy and fusion doctors should examine the T1 slope (for the correct or incorrect position) and C2-C7 sagittal vertical axis (this is a measure to determine if the spine is “plumb” in a straight line and correct balance).
- If these two factors are out of alignment there is a higher risk kyphosis after laminoplasty (The bone/fusion collapsed causing a “hunchback,” curve in the patient), which is accompanied by posterior neck muscle damage.
- The researchers warn that these important preoperative parameters have been under-estimated in anterior cervical discectomy and fusion.
- Forty-one (41) patients who underwent ACDF with a stand-alone polyether-ether-ketone (PEEK) cage at one-year follow-up. Fifty-five segments (27 single-segment and 14 two-segment fusions) were included.
- The subsidence (collapse) and pseudarthrosis (non-union) rates based on the number of segments were:
- 36.4% collapse
- 29.1% non-union
- CONCLUSION: Surgeons should examine and be aware of the risk factors associated with T1 slope (for the correct or incorrect position).
Surgical correction of the cervical spine curve during fusion surgery. Does it help? Why doesn’t it help?
In our non-surgical regenerative medicine injection techniques we recognize that to help the patient who sufferers from chronic neck pain, we must address and correct problems of the curvature of the cervical spine to achieve the best results. Surgeons also look at the curvature of the spine and its correction as a possible aid in helping their patients.
In December 2018 in the medical journal Therapeutics and Clinical Risk Management, (12) surgeons asked: “Is correction of segmental kyphosis necessary in single-level anterior cervical fusion surgery?” Here is how they answered that question:
- They examined 181 patients (99 males and 82 females) who underwent single-level ACDF surgery.
- There were 32 patients in the non-correction of curve group and 149 patients in the correction of the curve group.
- Surgical correction of segmental kyphosis in single-level cervical surgery contributed to balanced cervical alignment in comparison with those without satisfactory correction. However, the researchers could not demonstrate that the correction of segmental alignment is associated with better recovery in clinical outcomes.
What does this mean? It means that fusion is a complicated surgery and affects the natural movement of the neck, even when the natural curve of the spine is restored. Let’s go back to this study. The researchers focus on disc height at the fusion level.
- “On the basis of our general practice, we recommended that the restoration of disc height in the index level is essential to correct segmental angle. However, risk factors for progressive cage subsidence, such as endplate excessive resection and oversized cage insertion with excessive distraction, should also be avoided during surgery”
The final outcome of a successful cervical fusion is that the vertebrae can no longer move.
The final outcome of a successful cervical fusion is that the vertebrae can no longer move. This will prevent the nerve from getting pinched, BUT, the neck still moves. The neck’s motion is now transferred to the vertebrae below the fusion and above the fusion. In essence, the problem the surgery sought to fix only transferred excessive pressures to the vertebrae below it and above it. This is why people with cervical fusions inevitably, a year to three years later get the symptoms back
Now, by definition, that means if somebody is recommended a cervical fusion it means that the doctor is saying that it’s instability causing the problem. In my opinion, the best treatment for cervical instability is Prolotherapy of the neck, not cervical fusion. If it is the excessive movement of the vertebrae that is pinching on the nerves cause terrible pain, migraine headaches, vertigo, all types of symptoms, then Prolotherapy can strengthen the cervical ligament, address the symptoms and not rob the patients of their natural neck movements.
Cervical fusion – there is an option – it starts with DMX vs MRI
A DMX is a digital motion X-ray. If you watch the video below you may be somewhat amazed at what the DMX can show as opposed to a convention X-ray or a conventional MRI. The DMX shows your cervical spine in motion. The DMX is a tool we rely on to help us treat patients with very difficult chronic neck pain and symptoms.
As opposed to an MRI, DMX, or sometimes referred to as a cineradiography or videofluoroscopy, can show spinal and peripheral joint instability in real-time and how it impacts your quality of life. Whereas MRI is a tool that confirms you need surgery, DMX is a tool that can help confirm that you do not need surgery. The DMX gives us the tool of showing your neck in real-time motion and revealing more clues to the true nature of your problem than a static image can.
Caring Medical research on alternatives to Discectomy and Fusion
In our practice, we continue to see a large number of patients with a myriad of symptoms related to cervical neck instability including severe pain, problems of balance, headaches, and loss of mobility. These people are often confused, many times frightened by recommendations to complicated cervical neck surgeries they don’t understand.
Many of these people have been told that their problem is a problem of degenerative cervical disc disease. After years of prolonged pain and conservative care options such as chiropractic, massage, physical therapy, anti-inflammatories, pain medications, cortisone injections, and cervical epidurals that eventually fail, the only recourse, these people are told, is neck surgery.
Surgical recommendations are described in a way to the patient that seemingly makes sense as the only solution to their problems.
- The surgery will help, the patient is told, because it will cut away the cervical vertebrae bone that is pressing on the nerves
- The surgery will fuse the cervical vertebrae in place so the vertebrae do not shift out of place and press on the nerves again.
- The cervical disc that has been flattened or herniated is replaced with an artificial implant or bone from the pelvis.
Surgical recommendation for degenerative disc disease may not address the patient’s real problems – cervical neck ligament damage
In neck and spine surgery, doctors focus on degenerative disc disease and its treatment, anterior cervical discectomy and fusion and cervical decompression surgery to remove whole or part of the cervical vertebrae to allow space on compressed nerves and to fix the instability by fusing vertebral segments together. In the case of C1-C2 instability, these two vertebrae are fused posteriorly (behind) to limit their amount of movement. The goal is to limit pressure on the nerves.
However, it may limit motion to such an extent that patients become completely unable to move that portion of their neck. In addition, fusion operations can accelerate the degeneration of adjacent vertebrae as the motion in the neck is distributed more on these tissues.
- The cervical capsular ligaments are the main stabilizing structures of the facet joints in the cervical spine and have been implicated as a major source of chronic neck pain. Such pain often reflects a state of instability in the cervical spine and is a symptom common to a number of conditions such as disc herniation, cervical spondylosis, whiplash injury, and whiplash-associated disorder, post-concussion syndrome, vertebrobasilar insufficiency, and Barré-Liéou syndrome.
When the capsular ligaments are injured, they become elongated and exhibit laxity, which causes excessive movement of the cervical vertebrae.
- In the upper cervical spine (C0-C2), this can cause symptoms such as nerve irritation and vertebrobasilar insufficiency with associated vertigo, tinnitus, dizziness, facial pain, arm pain, and migraine headaches.
- In the lower cervical spine (C3-C7), this can cause muscle spasms, crepitation, and/or paresthesia in addition to chronic neck pain.
- In either case, the presence of excessive motion between two adjacent cervical vertebrae and these associated symptoms is described as cervical instability.
Therefore, we propose that in many cases of chronic neck pain, the cause may be underlying joint instability due to capsular ligament laxity. Furthermore, we contend that the use of comprehensive Prolotherapy appears to be an effective treatment for chronic neck pain and cervical instability, especially when due to ligament laxity. The technique is safe and relatively non-invasive as well as efficacious in relieving chronic neck pain and its associated symptoms.
Stabilizing the unstable neck – degenerative disc disease vs. degenerative ligament disease
Back to our 2014 research headed by Danielle R. Steilen-Matias, PA-C, published in The Open Orthopaedics Journal. Here we outline that the problems of the cervical neck are not always problems of degenerative disc disease but problems of degenerative ligament disease. This explains why traditional treatments focused on the discs will not be successful in the long-term.
In another of our published research studies, in the European Journal of Preventive Medicine, we presented the following findings:
- Ninety-five percent of patients reported that Prolotherapy met their expectations in regards to pain relief and functionality. Significant reductions in pain at rest, during normal activity, and during exercise were reported.
- Eighty-six percent of patients reported overall sustained improvement, while 33 percent reported complete functional recovery.
- Thirty-one percent of patients reported complete relief of all recorded symptoms. No adverse events were reported.
We concluded that statistically significant reductions in pain and functionality, indicating the safety and viability of Prolotherapy for cervical spine instability.(14)
If you have a question about options to Anterior Cervical Discectomy and Fusion, you can get help and information from our Caring Medical Staff.
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