Cervical disc disease and difficulty swallowing – cervicogenic dysphagia
Ross A. Hauser, MD. Caring Medical Florida
Danielle R. Steilen-Matias, MMS, PA-C. Caring Medical Florida
Treating Cervical Spine Instability is treating swallowing difficulties
- In this article, we will discuss the problems of swallowing difficulties as they relate to diagnosis of cervical spine disorder or cervical instability caused by weakened, torn, damaged ligaments in the neck.
- Cervical instability in the neck has been linked to swallowing difficulties, diagnosed as cervicogenic dysphagia.
- Cervical instability has been linked to cervical spine nerve compression which can be an “unseen” cause of swallowing difficulties.
- Cervicogenic dysphagia is not a problem that can be treated in isolation, it is likely one of a myriad of symptoms related to neck pain and neck hypermobility.
When a patient comes into our clinic with problems of swallowing difficulties, the swallowing difficulties are usually not a problem in isolation. While patients may tell us of their swallowing difficulties, most come in with primary complaints of neck pain or neck instability, whiplash associated disorders, or post-concussion syndrome. Swallowing difficulties may be accompanied by headaches, dizziness, hearing problems, severe muscle spasms in the neck, to name but just a few symptoms.
In this article, we will present research, clinical observation, and patient outcomes to suggest that treating instability in the cervical spine with regenerative proliferative injections can help many patients with swallowing difficulties.
In 2013, noted Croatian musculoskeletal researcher Vjekoslav Grgić published a paper linking cervical spine instability to swallowing difficulties. (1) He also noted that this association was rarely acknowledged and for the most part ignored. We are going to present research below that takes us to 2020 and see how much has changed in 7 years. Surprisingly, it will be not much.
Here is Dr. Grgić’s review summary. See if this sounds familiar to your own case:
“Cervical spine disorders which can cause swallowing difficulties (cervicogenic dysphagia) are chronic multisegmental/musculoskeletal dysfunction (dysfunction=functional blockade) of the facet joints, changes in physiological curvature of the cervical spine, degenerative changes (anterior osteophytes (bone spurs), anterior disc herniation, osteochondrosis, osteoarthritis), inflammatory rheumatic diseases, diffuse idiopathic skeletal hyperostosis (extensive amount of calcification that occurs within the spinal ligaments in the condition), injuries, conditions after anterior cervical spine surgery, congenital malformations and tumors.
According to our clinical observations, degenerative changes in the cervical discs and facet joints and chronic musculoskeletal dysfunction of the cervical spine facet joints are disorders that can cause swallowing difficulties.
However, these disorders have not been recognized enough as the causes of dysphagia and they are not even mentioned in differential diagnosis.“
Next is a video from Ross Hauser, MD., where the cervical spine instability is associated with cervical nerve dysfunction.
In this video Ross Hauser, MD explains the functional dynamics and possible solutions to swallowing difficulties.
Video Summary Transcript
Swallowing involves many of the cranial nerves:
- Cranial Nerve V or the trigeminal nerve, involves the muscles of biting, chewing and swallowing
- Cranial Nerve VII or the facial nerve which in addition to assisting in swallowing is involved with taste sensation and salivary glands
- Cranial Nerve X or the Vagus Nerve
- The Vagus nerve plays a vital role in the pharyngeal phase of swallowing. This is what happens during this phase:
- The vocal cords close the larynx to help keep food and liquids from entering the airway and lungs. As the larynx closes, the epiglottis (the skin flap that helps prevent choking) moves to cover it.
- Patients with swallowing difficulties caused by a disruption in the pharyngeal phase may suffer from:
- Coughing during swallowing
- Breathing difficulties during swallowing
- A choking sensation
- A change in voice during swallowing
- More severe cases may include food particles passing into the lungs and causes pneumonia-like symptoms or pneumonia itself.
- The Vagus nerve plays a vital role in the pharyngeal phase of swallowing. This is what happens during this phase:
- Cranial Nerve IX or glossopharyngeal nerve which moves muscles of the tongue and throat
- Cranial Nerve XII or the hypoglossal nerve which controls muscles in the pharynx (throat) and helps move found out of the mouth to the esophagus.
All these nerves run around the front of the cervical spine ‘s vertebrae, especially at C1 – C2. When somebody does have cervical instability it’s normally because of excessive stretching of the ligaments in the back of the neck. When these ligaments are weak, injured or torn what happens is the cervical vertebrae move forward when they move forward they can impair the nerve’s impulse through these various nerves. More symptoms such as choking on excretions, spit or mucus can occur. Difficulty in talking may occur as if your muscles are too weak to talk.
In our office, we use injection techniques like Prolotherapy to help stabilize the cervical spine. In many patients, we can reverse these symptoms by stabilizing the cervical spine and restoring the neck’s natural curve. This is explained below.
Even though I have neck problems I was sent for an endoscopy – Esophagogastroduodenoscopy
Often we will hear a story, it goes something like this:
I have had chronic problems in my neck. One of my problems is that, over time, I have found it more difficult to swallow foods. I was sent for an endoscopy to rule out digestive problems, I have already had enough x-rays and MRI to rule out cancer. I know the swallowing difficulty is from my neck problems. My diet over the last few months has increasingly become a steady menu of soups and broths. I feel something is stuck in my throat, I belch a lot, I get anxious about eating for fear of choking on my food. I also find that many times when I try to swallow I feel like I am going to faint or pass out.
My endoscopy was inconclusive
“If she held her head still, she was able to swallow”
Swallowing difficulties and bone spurs
There is not much research in the medical community that focuses solely on swallowing difficulties in relation to cervical spine instability. But there are many clues that clearly makes a connection.
In the April 2017 issue of the Journal of bodywork and movement therapies, a combined team of researchers from the University of Padova and the University of Bologna in Italy documented a case history of a young female patient with swallowing difficulties.(2)
- The patient complained of pain on the neck and swallowing dysfunction that was reduced by means of isometric contraction of cervical muscles. Isometric contraction is a routine exercise where the muscle and joint are held in a static position.
- In other words, the patient was able to find a position where if she held her head still she was able to swallow. If she stabilized her neck, she could swallow.
In this case study, the doctors performed an MRI that revealed an anterior C5-C6 disc protrusion associated with a lesion of the anterior longitudinal ligament. The barium radiograph showed a small anterior cervical osteophyte (bone spur) at the C6 level.
Conclusion: Diagnostic hypothesis was a combination of cervical disc dysfunction associated with C6 osteophyte and reduced functional stability AND a ligament tear.
- So we have a clue, ligament tear, cervical neck instability causes swallowing difficulties. Stabilize the neck, you can swallow.
Searching for clues when surgery and treatment fail to correct swallowing difficulties.
We have seen many patients with degenerative cervical spinal disease who can no longer tolerate continued high dosage narcotic painkillers or the anxiety or depression trip after trip to specialist after specialist is causing them. One clue that we may be able to help these people with their challenges including that of swallowing difficulties is if you put them in a cervical collar, do they get relief? If the answer is yes, then the collar is providing the missing cervical neck instability.
We do see people with advanced degenerative cervical disc disease who have or had significant bone spur formation. Many of these patients have had surgery to remove the bone spurs, yet their swallowing difficulties remained. If it was not the bone spurs pressing on the esophagus, what could it be? Why do these people still have swallowing difficulties after surgery? Let’s find out.
Swallowing difficulties and Diffuse idiopathic skeletal hyperostosis – “an underappreciated phenomenon”
Similarly, Cervicogenic dysphagia can be brought on by diffuse idiopathic skeletal hyperostosis, (DISH) a condition where the cervical ligaments and their attachments to the vertebrae (the entheses) undergo calcification and ossification. In general terms, the soft tissue has calcified or turned into bone spurs. The bone spurs cause esophageal obstruction. Aging patients, men more so than women are susceptible to swallowing difficulties related to diffuse idiopathic skeletal hyperostosis.
Diffuse idiopathic skeletal hyperostosis is a more common disorder than some doctors thought. Doctors in the Netherlands issued this warning in The Spine Journal:
“Diffuse idiopathic skeletal hyperostosis as a cause of dysphagia and/or airway obstruction may be an increasing and underappreciated phenomenon.”(3)
Diffuse idiopathic skeletal hyperostosis can be brought on by degenerative wear and tear, as mentioned above, as a result of age or overuse. As with any bone spur, bone spurs form to help stabilize a joint. Diffuse idiopathic skeletal hyperostosis develops to stabilize cervical instability by turning the soft tissue attachments that are failing, into bony attachments. This, unfortunately, distorts the cervical spine and leads to various cervical related symptoms beyond swallowing difficulties.
- Another clue linking the cervical ligaments to swallowing difficulties.
Swallowing difficulties can be a degenerative disorder of weakened cervical neck ligaments
Now let’s explore a March 2019 study in the medical journal Spine.(4) This research comes from the Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University, Japan. the goal of this study was to investigate whether cervical (neck) alignment is related to dysphagia in patients with cervical diffuse idiopathic skeletal hyperostosis.
This is what the researchers found puzzling:
- Diffuse idiopathic skeletal hyperostosis involves a wide range of ligamentous ossifications (calcifying of the ligament), which can cause dysphagia. However, even patients with a high degree of ossification can have only mild dysphagia. Dysphagia results from esophageal compression due to ossification; however, the exact cause of dysphagia is unknown.
So they looked at 5 patients with advanced dysphagia due to anterior cervical hyperostosis (bone spurs) who underwent bone removal, and five patients with mild symptoms who were only monitored.
- The Eating Assessment Tool-10 (EAT-10) (most of you are aware this is a swallowing evaluation measurement) indicated a high degree of dysphagia in the people who had surgery for bone removal compared with the non-surgical group.
- In the surgery group, the EAT-10 score significantly decreased post-operatively and improvement of dysphagia was observed.
- The conclusion was: “restriction of flexion due to cervical spine ankylosis may be one of the reasons for dysphagia in patients with DISH.”
What is this research telling us?
- Swallowing difficulties can be a degenerative disorder of weakened cervical neck ligaments
- Weakened cervical neck ligaments cause neck instability
- Neck instability causes abnormal motion in the cervical vertebrae
- Abnormal motion causes bone spurs
- Bone spurs cause swallowing difficulties.
Swallowing difficulties: A problem of autonomic nervous system dysfunction?
Swallowing difficulty may also be due to autonomic nervous system dysfunction that may be caused by Barré-Lieou Syndrome, also known as posterior cervical sympathetic syndrome and cervicocranial syndrome. This can be a severely debilitating condition in which the autonomic nervous system of the head and neck area is not working correctly. In almost all patients we see, there is a link between cervical spine instability and the onset of Barré-Lieou Syndrome.
Swallowing is a very complex process that involves the mouth, throat, and esophagus. Many nerves and muscles affect the correct functioning of these parts, and while part of the process of swallowing is under voluntary control, much of it is involuntary. Cervical spine instability can affect both the voluntary and involuntary response.
- Another clue linking the cervical ligaments to swallowing difficulties.
Swallowing difficulties: A problem of age?
The muscles and support structures of the neck make for good swallowing function. As we age degenerative disease can affect the muscles, tendons, and ligaments that help us swallow.
A study in the journal Current Opinion in Otolaryngology & Head and Neck Surgery (5) suggests that surgeons and clinicians explore multidisciplinary perspectives and initiatives, (it is not just one thing causing the problem and you may need to explore “innovative” and multiple treatments).
One thing that the researchers suggest as innovative is swallowing exercises. This is to build up the muscular structure of the swallowing mechanism. To build up muscle you need strong tendons and ligaments. You have to deal with the problem of cervical instability.
- Another clue linking the cervical ligaments to swallowing difficulties. It should be clear at this point that there is a link. The next step is how cervical instability affects posture.
Swallowing difficulties: A problem of posture?
In the medical journal Dysphagia, (6) researchers discussed the relationship between oropharyngeal (back of the throat) dysphagia and its relationship to cervical spine disorders and postural disturbances due to either congenital or acquired disorders.
They write: “The etiology and diagnosis of dysphagia are analyzed, focusing on cervical spine pathology associated with dysphagia as severe cervical spine disorders and postural disturbances largely have been held accountable for deglutition (swallowing) disorders.”
- and osteophytes are the primary focus in finding the link between cervical spine disorders and dysphagia.
“It is important for physicians to be knowledgeable about what triggers oropharyngeal dysphagia in cases of cervical spine and postural disorders. Moreover, the optimum treatment for dysphagia, including the use of therapeutic maneuvers during deglutition, neck exercises, and surgical treatment, (should be discussed with patients).”
Swallowing difficulties caused by the odontoid process of the axis because of C1/2 instability
A December 2019 paper from the New York Chiropractic & Physiotherapy Centre, New York Medical Group, Hong Kong, China was published in the journal Clinical medicine insights. Case reports.(7) The paper was titled: “Unusual Cause of Dysphagia in a Patient With Cervical Spondylosis.” What was the unusual cause? Cervical spine instability. Here is the unusual case presented:
“Given that causes of dysphagia differ from patient to patient, individualized treatment plans tailored toward patients’ specific conditions are needed. Here we present a case of an elderly woman with upper neck stiffness and dysphagia sought chiropractic treatment. Radiographic findings suggested cervical spondylosis with a vertical atlantoaxial subluxation. Following 20 sessions of chiropractic treatment, the patient experienced complete relief from neck problems and difficulty in swallowing.
Rhythmic swallowing movements are controlled by a central pattern-generating circuit of the brain stem. In this case, the brain stem could have been compressed by the odontoid process of the axis due to C1/2 instability.
Cervicogenic dysphagia is a cervical cause of difficulty in swallowing. Cervical complaints in the context of dysphagia are mostly under-estimated. A high degree of clinical suspicion is pivotal in timely intervention.”
In this case, results may have been achieved because the c1/c2 vertebrae were adjusted back into alignment.
Swallowing difficulties: TMJ Involvement with cervical instability
In the Journal of Oral and Maxillofacial Surgery: The official journal of the American Association of Oral and Maxillofacial Surgeons, (8) doctors looked at oral stage dysphagia (swallowing difficulties that begin in the mouth) with potential effects on function and patient well-being.
To examine the effects of function in TMJ patients, the doctors looked at 178 TMJ/TMD temporomandibular joint dysfunction patients.
- Of the 178 TMD participants, 99% reported at least one symptom or sign of oral stage dysphagia.
- Individuals presenting with
- subluxation of the jaw (80%),
- degenerative joint disorder (67%),
- and myofascial pain disorder (40%) reported oral stage dysphagia most frequently.
There is no doubt that TMJ patients suffer from swallowing difficulties, but do they have cervical instability as well and is this making swallowing more challenging?
In many patients, we see with primary problems related to neck pain and cervical instability we see problems of TMJ. In many patients that we see with problems of TMJ, we see cervical neck pain. Surprisingly, despite the research suggesting the connection, many patients were not made aware that their jaw pain could be a problem originating in the neck.
In the medical journal Clinical Oral Investigations, (9) oral surgeons in Belgium made a connection.
They conducted a study looking for possible correlations between clinical signs of temporomandibular disorders (TMD) and cervical spine disorders.
- Thirty-one consecutive patients with symptoms of TMD and 30 controls underwent a standardized clinical examination of the masticatory system, evaluating the range of motion of the mandible, temporomandibular joint (TMJ) function and pain of the TMJ and masticatory muscles.
- Afterward, subjects were referred for clinical examination of the cervical spine, evaluating segmental limitations, tender points upon palpation of the muscles, hyperalgesia, and hypermobility.
- The results indicated that segmental limitations (especially at the C0-C3 levels) and tender points (especially in the sternocleidomastoideus and trapezius muscles) are significantly more present in patients with TMJ than the control subjects
There is a problem with the chewing muscles contributing to problems in your cervical spine and your entire posture
Swallowing difficulties are hard to manage because in some patient cases, possible yours, you have to continuously “peel the onion,” to get to the true root cause of the patient’s problem. Swallowing difficulties may not be a primary complaint of a patient, but one of the many complaints that seemingly have no answer. Here we are examining whether the muscles of the jaw are negatively impacting your cervical spine and if your swallowing difficulties, indeed many problems you are suffering from, may be from this connection.
In the European Journal of Orthodontics, (10) doctors in Japan made a connection:
- In this study, the doctors compared the mandibular stress distribution and displacement of the cervical spine. In simple terms, how TMJ instability and hypermobility of the jaw negatively affected the cervical spine.
- What did they find? ” (an) imbalance between the right and left masticatory muscles antagonistically act on displacement of the cervical spine, i.e. the morphological and functional characteristics in patients with mandibular lateral displacement may play a compensatory role in posture control.”
What? The TMJ altered your posture by stressing your cervical spine? Isn’t posture a problem of swallowing difficulties? Isn’t posture a problem of everything?
Surgery for swallowing difficulties – high risk – low reward?
When you look at the research above, especially when the bulk of it comes from oral and neurosurgeons, it is not difficult to see that surgery for swallowing difficulties is a high risk – low reward procedure. Let’s be clear though, there are times when surgery is necessary, especially if there is an anatomical deformity that is possibly life-threatening.
Now, what about the bone spurs?
Using exercise to help swallowing difficulties in cervical instability patients is clearly superior to surgery for patients desiring to avoid surgery. The problems of surgical correction of swallowing difficulties from bony overgrowth (osteophytes or bone spurs) is documented in this research from Turkish surgeons from the Gulhane Military Medical Academy and Gelibolu Military Hospital.
This study was presented in The Journal of Craniofacial Surgery (11) and discusses the advantages and disadvantages of anterior cervical osteophytes surgical procedures. (A frontal incision into the throat area or the mouth to get at the cervical bone spurs).
The doctors looked at the operative records of anterior cervical osteophytes patients who did not benefit from conventional treatments and underwent osteophytectomy (bone spur removal).
Five patients were operated with the transcervical anterolateral method (incision into the neck), and 3 patients were operated with the transoral procedure (through the mouth). Those using the transcervical method were likely to encounter complications. Although the transoral procedure is much safer, the patients may face postoperative pain, long healing time, and morbidities as hematoma, cervical instability, and infection after surgery.
While both surgeries can improve swallowing difficulties, the price of complications and further instability in the future was warned about. The researchers did suggest that Transoral approach is not recommended due to slow healing times and postoperative pain, although it creates easier access to the spine.
Does surgery cause swallowing difficulties?
In March 2019 in the journal Clinical Neurology and Neurosurgery, (12) researchers at the David Geffen School of Medicine and the Department of Neurosurgery at Kaiser Permanente discussed the reported incidence of dysphagia after Anterior Cervical Discectomy and Fusion. The researchers commented that up to 79% (4 out of 5 surgical patients) will suffer from swallowing difficulties.
Please see our article Anterior Cervical Discectomy and Fusion – The evidence. Here we discuss the evidence that this surgery can cause more cervical spine instability and deformity
Returning to this study from March 2019, the researchers looked into what caused these problems of swallowing difficulties and further why it appears that doctors are not investigating this problem. The researchers noted: “There, however, have been no studies that have specifically looked at developing criteria for reducing the incidence of dysphagia for outpatient ACDFs.”
What caused the swallowing difficulties? The researchers found ONLY ONE THING:
- Single-level ACDF at the upper cervical spine (C2-3, C3-4) was found to be the only risk factor for dysphagia with a length of hospital stay of more than 48 hours.
- “These findings should be used for excluding patients who undergo outpatient single-level ACDF surgery to reduce significant postoperative dysphagia.”
Treating Cervical Spine Instability is treating swallowing difficulties
In this video, DMX imaging displays Prolotherapy results in before and after treatment images. This patient’s treatment had problems of a pinched nerve in the cervical spine resolved. Prolotherapy is discussed below. Prolotherapy is a regenerative medicine injection treatment that utilizes dextrose, a simple sugar as a proliferant to rebuild soft tissue structures.
This video demonstrates the alleviation of cervical disc herniation and the patient’s related symptoms.
- In this video, we are using a Digital Motion X-Ray (DMX) to illustrate a complete resolution of a pinched nerve in the neck and accompanying symptoms of cervical radiculopathy.
- A before digital motion x-ray at 0:11
- At 0:18 the DMX reveals a completely closed neural foramina and a partially closed neural foramina
- At 0:34 DMX three months later after this patient had received two Prolotherapy treatments
- At 0:46 the previously completely closed neural foramina is now opening more, releasing pressure on the nerve
- At 1:00 another DMX two months later and after this patient had received four Prolotherapy treatments
- At 1:14 the previously completely closed neural foramina is now opening normally during motion
We will see many patients who were told about surgeries
We will see many patients who were told about surgeries, such as those spoke above and offered surgical consultation for his/her problem with swallowing if there is a concern the problem is due to a diverticulum or outpouching of the throat. However, the surgical recommendation is often compromised by the difficulty in diagnosis.
Conservative treatments may be offered to see if the surgery is warranted or, better yet, avoided.
Recommendations to relieve the symptoms may include a bland diet, eliminating caffeine or alcohol from the diet, modifying the consistency of foods to make them easier to swallow, elevating the head while sleeping, or therapy to strengthen the swallowing muscles, particularly when the swallowing difficulty seems to be the result of neurological disorder. In certain situations drugs that slow the production of stomach acid, muscle relaxants or antacids may be prescribed.
However, the truth is, a person suffering from this often painful and debilitating condition may be seen by numerous specialists and yet find no resolution for the symptoms and, thus, no understanding as to why the condition exists at all.
In our office, we perform a physical examination and use our ultrasound and Digital Motion X-ray machine, described in the video above to get at the cause of the problem rather than to simply seek to treat the symptoms. This helps us determine, if, as often, we are looking at a dysfunction of the autonomic nervous system, a problem of posture, a problem of degenerative aging, a problem possibly of TMJ related challenges.
Swallowing difficulties as well as a host of other symptoms including neck, eye, and facial pain, cervical vertigo, dizziness and ringing in the ears, is very treatable using Prolotherapy to the neck ligaments.
Prolotherapy is, in our opinion, the safest and most effective non-surgical treatment for repairing ligament damage. It stimulates the body to repair the damaged and weakened areas by inducing a mild inflammatory reaction. Since the body heals by inflammation, Prolotherapy stimulates healing.
As mentioned earlier, swallowing difficulty may also be due to an autonomic nervous system dysfunction. While the actual cause of this dysfunction may be elusive, Neural Therapy to the head and neck area has been known to help with swallowing difficulties. Neural therapy involves the injections of anesthetics to help the nerves reset themselves. For example, if the patient had previously had surgery in the mouth or neck area, the scars would be injected as they can act as “interference fields” to the autonomic nervous system.
Research on cervical instability and Prolotherapy
Caring Medical Regenerative Medicine Clinics have published dozens of papers on Prolotherapy injections as a treatment in difficult to treat musculoskeletal disorders. We are going to refer to two of these studies as they relate to cervical instability and a myriad of related symptoms including the problems of swallowing difficulties or cervicogenic dysphagia.
In our own research, our Caring Medical research team published a comprehensive review of the problems related to weakened damaged cervical neck ligaments.(13)
This is what we wrote: “To date, there is no consensus on the diagnosis of cervical spine instability or on traditional treatments that relieve chronic neck instability issues like those mentioned above. In such cases, patients often seek out alternative treatments for pain and symptom relief. Prolotherapy is one such treatment that is intended for acute and chronic musculoskeletal injuries, including those causing chronic neck pain related to underlying joint instability and ligament laxity. While these symptom classifications should be obvious signs of a patient in distress, the cause of the problems are not so obvious. Further and unfortunately, there is often no correlation between the hypermobility or subluxation of the vertebrae, clinical signs or symptoms, or neurological signs (such as swallowing difficulties) or symptoms. Sometimes there are no symptoms at all which further broadens the already very wide spectrum of possible diagnoses for cervical instability.”
What we demonstrated in this study is that the cervical neck ligaments are the main stabilizing structures of the cervical facet joints in the cervical spine and have been implicated as a major source of chronic neck pain and in the case of cervicogenic dysphagia type symptoms, cervical instability.
If this article has helped you understand problems of swallowing difficulties and you would like to explore Prolotherapy as a possible remedy, ask for help and information from our specialists
1 Grgić V. Cervicogenic dysphagia: swallowing difficulties caused by functional and organic disorders of the cervical spine. Liječnički vjesnik. 2013 Apr 30;135(3-4):0-. [Google Scholar]
2 Verlaan JJ, Boswijk PF, de Ru JA, Dhert WJ, Oner FC. Diffuse idiopathic skeletal hyperostosis of the cervical spine: an underestimated cause of dysphagia and airway obstruction. The Spine Journal. 2011 Nov 1;11(11):1058-67. [Google Scholar]
3 Margelli M, Vanti C, Villafañe JH, Andreotti R. Neck pain and dysphagia associated to disc protrusion and reduced functional stability: A case report. Journal of Bodywork and Movement Therapies. 2017 Apr 1;21(2):322-7. [Google Scholar]
4 Kawamura I, Tominaga H, Tanabe F, Yamamoto T, Taniguchi N. Cervical Alignment of Anterior Cervical Hyperostosis Causing Dysphagia. Spine. 2019 Mar 1;44(5):E269-72. [Google Scholar]
5 Jardine M, Miles A, Allen JE. Swallowing function in advanced age. Current opinion in otolaryngology & head and neck surgery. 2018 Dec 1;26(6):367-74. [Google Scholar]
6 Papadopoulou S, Exarchakos G, Beris A, Ploumis A. Dysphagia associated with cervical spine and postural disorders. Dysphagia. 2013 Dec 1;28(4):469-80. [Google Scholar]
7 Chu EC, Shum JS, Lin AF. Unusual Cause of Dysphagia in a Patient With Cervical Spondylosis. Clinical Medicine Insights: Case Reports. 2019 Dec;12:1179547619882707. [Google Scholar]
8 Gilheaney Ó, Stassen LF, Walshe M. Prevalence, Nature, and Management of Oral Stage Dysphagia in Adults With Temporomandibular Joint Disorders: Findings From an Irish Cohort. Journal of Oral and Maxillofacial Surgery. 2018 Feb 20. [Google Scholar]
9 De Laat A, Meuleman H, Stevens A, Verbeke G. Correlation between cervical spine and temporomandibular disorders. Clinical oral investigations. 1998 Aug 1;2(2):54-7. [Google Scholar]
10 Shimazaki T, Motoyoshi M, Hosoi K, Namura S. The effect of occlusal alteration and masticatory imbalance on the cervical spine. The European Journal of Orthodontics. 2003 Oct 1;25(5):457-63. [Google Scholar]
11 Erdur Ö, Tasli H, Polat B, Sofiyev F, Tosun F, Çolpan B, Birkent H, Öztürk K. Surgical Management of Dysphagia Due to Anterior Cervical Osteophytes. Journal of Craniofacial Surgery. 2017 Jan 1;28(1):e80-4. [Google Scholar]
12 Aguilar DD, Brara HS, Rahman S, Harris J, Prentice HA, Guppy KH. Exclusion Criteria for Dysphagia for Outpatient Single-Level Anterior Cervical Discectomy and Fusion using Inpatient Data from a Spine Registry. Clinical Neurology and Neurosurgery. 2019 Mar 11. [Google Scholar]
13 Steilen D, Hauser R, Woldin B, Sawyer S. Chronic neck pain: making the connection between capsular ligament laxity and cervical instability. The open orthopaedics journal. 2014;8:326. [Google Scholar]