This is because the blood supply to the parathyroid glands, which are important organs in charge of calcium balance in the body, is affected during surgery, and once the blood supply is impaired, its function is bound to be affected, leading to postoperative hypocalcemia, resulting in numbness and convulsions. During cervical lymph node dissection surgery, the parathyroid glands and lymph nodes are similar in appearance, making them difficult to distinguish from each other, and sometimes even misincision may occur. Therefore, it is important to protect the parathyroid glands during surgery, and an experienced thyroid specialist can effectively prevent this from happening. The majority of patients with numbness in the hands and feet have temporary symptoms that improve significantly with a period of calcium supplementation, and permanent hypoparathyroidism is less common.