Laryngeal Nerve injuries during neck surgery

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The recurrent laryngeal nerve, known commonly as the vocal cord nerve, is the nerve that controls the vocal cords on each side of the neck. Both recurrent laryngeal nerves run from the bottom of the neck up along the trachea to enter the larynx (voice box) where it then controls how the vocal cords move and thus the recurrent laryngeal nerves control speech. Because the nerves come from below and run up the neck they are called "recurrent". The recurrent laryngeal nerves are located behind the thyroid gland on both sides and therefore are occasionally injured during surgery for the thyroid and parathyroid glands.

The drawing shows how the recurrent nerve branches off of the (yellow) vagus nerve down in the chest wrapping around the large arteries and then returns up the neck to get to the voice box. The recurrent laryngeal nerve in this diagram is purple. The thyroid has been removed in this diagram so you can see the nerve which normally runs behind the thyroid to enter the voice box to control the vocal cords. It is called "recurrent" because it goes into the chest and then "recurs" (runs backwards) up the neck.

The other laryngeal nerve that is often injured during neck surgery of all types is the superior laryngeal nerve. This nerve primarily controls the muscles of the larynx and pharynx--the upper part of the esophagus. Thus when this nerve is injured--as it very commonly is during anterior spinal fusion surgery--the patient has difficulty swallowing at times, or all the time. This can be a terribly debilitating problem.

Recurrent laryngeal nerve (RLN) injury is one of the most feared complications after thyroid and parathyroid surgery, or any surgery of the neck. Injury to the laryngeal nerve occurs much more often than doctors or surgeons will admit. Injury to this nerve can have a very significant effect on the patient's quality of life. Injury to a recurrent laryngeal nerve on one side of the neck produces paralysis of one vocal cord and thus the patient cannot speak. Injury to the vocal cord nerve on both sides of the neck is a much worse complication of thyroid and parathyroid surgery and makes it difficult for the patient to breath and typically requires a tracheostomy.

What are the symptoms of a laryngeal nerve injury?

Because the laryngeal nerve controls all of the internal muscles of the larynx (voice box) except the small cricothyroid muscle, injury of this nerve causes paralysis of the vocal cord on that side of the body. Symptoms of  laryngeal nerve injury include the loss of voice, difficulty in speech beyond a whisper, difficulty in catching your breath, and often difficulty swallowing--especially liquids which often can enter the trachea and cause coughing spells. Many patients have a hard time "catching their breath" often taking large gulps of air when trying to talk. The symptoms of vocal cord nerve injury occasionally can resolve over a week or two, but in the vast majority of cases it takes the nerve just under 3 months to begin working again.  Nerves that have been cut, stripped, burned with cautery or had a more serious injury rather than just manipulation during surgery may never work again. These patients will require additional operations or procedures on the vocal cord that is controlled by the injured nerve so they can gain some relief of these symptoms. 

Injury to the laryngeal nerve occurs in 4 to 30% of patients undergoing thyroid and parathyroid surgery which is directly related to the experience of the surgeon. Nerve injuries that are temporary and heal in a few months are observed between 5% and 30% according to various published studies [1 - 9].  Permanent nerve injuries that do not improve occur in 0.5% to 5% of all thyroid surgery patients.  Thus, vocal cord nerve injuries occur far more often than surgeons will admit and medical articles will claim. These complications are way under-reported and it is very common for surgeons to claim their rates of injury are far lower than they actually are. The risk of injury to the nerve is absolutely and directly related to the experience of the surgeon. Surgeons who have performed thousands of thyroid and parathyroid operations have rates of nerve injuries of less than 1.5% and they are almost always temporary injuries. 

Surgeons who perform fewer than 20 thyroid and parathyroid operations per year have nerve injuries 100 to 200 times more often than experts who perform several hundred operations per year and can have nerve injury rates of 20-30%. Unfortunately, there are only a handful of surgeons who perform hundreds of thyroid or parathyroid operations per year. This is why Dr Norman developed the Laryngeal Nerve Shield -- to help prevent or lessen the severity of vocal cord nerve injuries for all patients who are being operated on by surgeons at all skill levels. 

Although the laryngeal nerve is at risk for injury during surgery of the thyroid, parathyroid glands most commonly, these nerves are also at risk for injury for any neck operation including surgery for the, esophagus, larynx, and carotid arteries as well as anterior neck cervical fusion. In fact, most studies show that more than 80% of patients undergoing anterior spinal fusion surgery have dysfunction of their swallowing for months or years due to trauma of the laryngeal nerves as the thyroid is retracted to allow the surgeon access to the spine. 

Two prospective clinical trials have shown significantly faster return of recurrent laryngeal nerve function with amniotic membrane overlays.  The first, conducted at Yale University departments of surgery and endocrine surgery showed the incidence of overall post op nerve injury to be slightly decreased. But more impressive was the fact that patients who did suffer a nerve injury and were treated with the amniotic membrane regained normal nerve function more than twice as fast as those who did not.  Published Article

A second prospective clinical trial at the Norman/Clayman Endocrine Institute in 100 consecutive patients operated on by the highest volume thyroid surgeons in the US showed a decrease in the overall incidence of nerve injury from 8% to 4.5%.  Like the results seen in the Yale study, patients who did have a laryngeal nerve injury recovered their voice and normal laryngeal nerve function on average more than twice as fast as those that did not have amniotic membrane placed.  (article in press, 2021) 

Laryngeal nerve injuries are more common for surgeons who perform neck surgery of any kind infrequently. But even the most experienced and busiest neck surgeons have laryngeal nerve injuries and unfortunately, it happens even when the operation appeared to go perfectly.  Surgeons are taught to treat the laryngeal nerves very carefully, but sometimes just exposing the nerve, or traction on tissues near the nerve can render it non-functional for months--or even years.  Since even the best surgeon cannot always tell which patient will have a nerve injury and the terrible problems that it brings, surgeons are now using Amnioduvet's Nerve Shield on all exposed laryngeal nerves to help prevent these life-changing problems. 

Make sure your surgeon uses the Amnioduvet Laryngeal Nerve Shield!

Aside from choosing a high-volume surgeon, the best thing you can do to increase your chances of a good outcome is to ask your surgeon to use the Laryngeal Nerve Shield which was developed by Dr Norman to protect the nerve and help it heal faster. This amniotic nerve "blanket" or "duvet" is available in virtually all hospitals in the US and Canada.  Drs Norman and his team of surgeons at the Hospital for Endocrine Surgery use the amniotic nerve patch on every patient with an exposed nerve to give every patient the best possible outcome. They do not compromise for the safety of their patients. You should expect the same of your surgeon--so talk to your surgeon and make sure you have the potential benefits of this new technology.

Dr Norman and his team of world-expert surgeons developed the Amnioduvet amniotic nerve shield and specifically for head and neck surgery to protect both the superior and the recurrent laryngeal nerve. Ask your doctor to give you the best chance of a great outcome!

Nerve monitoring endotracheal tubes have never been shown to help prevent injury to the recurrent laryngeal nerve during thyroid or parathyroid surgery. In fact, there are a number of studies including one by Dr Norman's group that showed the rate of nerve injury was almost twice as high in patients where the nerve-monitoring tube was used compared to operations where nerve monitoring wasn't used. This is because the surgeons "think" the nerve monitoring device will save the nerve and they are more aggressive ending up with higher rates of nerve injury.  Do NOT let your surgeon tell you that he/she monitors your vocal cord nerve during the operation to keep your nerve safe. It does not do this. He/she is using it so they don't get sued for your injury. They are almost always doing it to protect themselves.

Of course you understand that using the Amnioduvet Laryngeal Nerve Shield does not guarantee that you will not have a vocal cord nerve injury during your thyroid or parathyroid operation or other neck surgery. There is no product that can guarantee a great outcome. But if the most experienced surgeons neck surgeons in the world -- with extremely low rates of laryngeal nerve injury -- use it on all of their patients with an exposed nerve, then don't you want this same opportunity for nerve protection that their patients get?

Your surgeon wants to avoid nerve injuries too!

Your surgeon is very concerned about laryngeal nerve injuries just like you. Surgeons are always very careful around the recurrent nerve and they take many precautions to help avoid injury to this nerve. The Amnioduvet Laryngeal Nerve Shield is a brand new technology and your surgeon may not even know about it yet! Use the "Get a Shield For Me" button here to contact an Amnioduvet Sales Representative who will contact your surgeon for you. They will make sure to have this very specialized product in the operating room during your operation -- should your nerve be exposed and should it be appropriate and a potential benefit to you.