Vocal Cord Paralysis

Basic description

Human beings have two vocal cords (the medical term is vocal fold) that are separate, yet function like one unit. These are the right and left true vocal cords (the lower sets of tissue that stretch across the larynx or voice box). They are controlled by our brains and receive signals to open and close from the brain through two nerves.

The "parent" of the nerves that control the voice/voice box in a push/pull fashion is called the Vagus Nerve. Stemming from the Vagus are two nerves. One, the Recurrent Laryngeal Nerve (RLN), carries information to one set of muscles to open our voice box (allowing us to breathe) and opposing information to another set of muscles to close it (allowing us to talk). The other important nerve is the Superior Laryngeal Nerve (SLN), which has two main functions. One is to take information from the larynx back to the brain (this part of the SLN is responsible for telling you when you need to cough, for example). The other part of the nerve controls the muscle that lets us raise pitch and talk or sing higher.

If the signals and information carried by these nerves get interrupted, the end result is that the muscles don’t make the vocal cords move. We call this impaired vocal fold mobility. The reason we use this term is because the vocal fold is not always paralyzed. Sometimes it still moves, just not well. Also, we tend not to use the term "paralysis" unless we know the injury will NOT recover and healing can take up to a year.


  • Weak, breathy, airy, or, "mousey" voice
  • Trouble projecting voice or being heard over other people
  • Difficulty/strain speaking at all, or getting tired from speaking during a normal day
  • Trouble swallowing; things going down the "wrong way"
  • Weak cough, trouble clearing out phlegm
  • Voice that splits or cracks, or feels like two voices
  • Voice wears out easily and feels a little better/stronger after resting it


  • Injury during surgery (the nerve is long and surgery in the brain, neck, or chest can result in an injury)
  • Trauma to the neck (such as from a fall or car accident)
  • Tumors or growths in the head, throat, or chest area
  • Neurological Conditions like Parkinson’s disease or stroke
  • Infections– stemming from bacteria and viruses that attack and damage nerves. Most often, this is a temporary injury, but sometimes, the nerve does not recover. Among the most common are those related to Lyme disease, herpes, and other conditions.

Trauma to the neck

  • Car accident
  • Falls
  • Gunshot wound
  • Stab wound
  • Sports injuries

Tumors (Growths)

  • Thyroid mass
  • Brainstem mass
  • Skull Base Mass
  • Lung/chest mass
  • Enlarged chamber of the heart (rare)

Neurological Conditions

  • Multiple Sclerosis
  • Parkinson’s Disease
  • Amyotropic Lateral Sclerosis (Lou Gehrig’s disease)
  • Myasthenia
  • Stroke
  • Bleeding into the brain
  • Lyme Disease, certain toxic substances that reduce nerve function


there are some bacteria and viruses that are known to attack nerves and damage the nerve. Most often, this is a temporary injury, but sometimes, the nerve does not recover.

  • Borrelia burgdorferi—Lyme Disease*
  • Corynbacterium diphtheriae—Diptheria
  • Methicillin Resistant Staph aureus—MRSA
  • Herpetic Viruses (Varicella and Zoster, Herpes Simplex Virus)—cold sores, shingles*
  • Epstein Barr Virus (EBV)—mononucleosis*
  • Cytomegalovirus (CMV)*
  • Human Immunodeficiency Virus (HIV)

*more commonly seen


  • CT scan (a computerized x-ray that looks at multiple images) over the course of the nerve[s] in question
  • Laryngeal EMG (a test that diagnoses voice and swallowing disorders)
  • Tests for bacterial and viral cultures
  • Laryngoscopy (an examination of the vocal folds, larynx, and back of the throat using a scope) or videostroboscopy (a test that measures the movement of the vocal cords during speaking or singing)

Treatment Options

There are basically three approaches:

  • Re–innervation – transplanting a nerve in the neck to the affected areas to stimulate the voice muscles
  • Injection laryngoplasty – minimally invasive injection of a compound into the larynx to correct nerve damage, usually without scarring, depending on the specific compound used
  • Laryngeal framework surgery – a minimally invasive approach that boosts the cartilage surrounding the voice box to allow for better vibration and sound/voice

Every person is different. The best option for you will be the best option for YOU.