The recurrent laryngeal nerve is the most commonly damaged nerve during throidectomy.

recurrent laryngeal nerve

One of two offshoots of the vagus nerve that connect to the larynx. It is located below the larynx.

The major risk of parathyroidectomy is injury to the recurrent laryngeal nerve (a nerve that lies very near the parathyroid glands and serves the larynx or voice box).

The nerve is best known for its importance in thyroid surgery, as it runs immediately posterior to this gland. If it is damaged during surgery, the patient will have a hoarse voice. Nerve damage can be assessed by laryngoscopy, during which a stroboscopic light confirms the absence of movement in the affected side of the vocal cords. Similar problems may also be due to invasion of the nerve by a tumor or after trauma to the neck. A common scenario is paralysis of the left vocal cord due to malignant tumour in the mediastinum affecting the left branch of the recurrent laryngeal nerve. The left cord returns to midline where it stays. If the damage is unilateral, the patient may present with voice changes including hoarseness. Bilateral nerve damage can result in breathing difficulties and aphonia, the inability to speak. The right recurrent laryngeal nerve is more susceptible to damage during thyroid surgery due to its relatively medial location.