The risk of secondary thyroid surgery far exceeds the risk of primary surgery because the core point of thyroid surgery is to stop bleeding and to protect the superior laryngeal nerve, the recurrent laryngeal nerve, and the parathyroid glands. After the first surgery, scarring is inevitable in the local surgical incision and in the surgical field, where the tissue is dense. During the second surgery, the superior laryngeal nerve is easily damaged during the separation of the thyroid gland because of the dense tissue, which may result in dullness of the voice or choking on water. Injury to the recurrent laryngeal nerve can easily lead to hoarseness, or even choking when the recurrent laryngeal nerve is damaged bilaterally. Injury to the parathyroid glands can cause hypocalcemia, which manifests as hand and foot twitching. Therefore, secondary surgery of the thyroid gland is very large and prone to serious consequences due to medically induced injury.