This study collected data from patients who underwent thyroidectomy in the Breast and Thyroid Surgery Department of Shandong Provincial Hospital from January 2020 to December 2023 by reviewing medical records. The main calculation indicator was the changes in PTH before and after surgery. This study grouped patients based on the number of central lymph nodes under postoperative paraffin pathology, and statistically analyzed the changes and differences in PTH before and after surgery in different groups to verify the relationship between the number of central lymph nodes in the thyroid gland and parathyroid function, and to provide reference for surgical selection in thyroid cancer patients with multiple cervical lymph node metastases.

The central lymph nodes of the thyroid gland refer to the lymph nodes located around the thyroid and trachea. The central lymph nodes are the primary site of thyroid cancer metastasis, and therefore play an important role in thyroid surgery. In thyroid surgery, preventive central lymph node dissection is a routine procedure, but during this process, the parathyroid gland may be impaired due to surgical injury or insufficient blood supply.

Hypothyroidism, also known as parathyroidism, is a common complication of thyroid surgery. When the parathyroid gland is accidentally injured or its blood supply is disrupted, it can lead to insufficient production of parathyroid hormone. Parathyroid hormone is a key hormone that regulates blood calcium levels. Insufficient levels can lead to hypocalcemia, manifested as hand and foot spasms, muscle spasms, and even arrhythmia.

From a surgical perspective, the number of lymph nodes in the central region of the thyroid gland may affect the preservation and functional protection of the parathyroid gland. A large number of lymph nodes indicates that they may have a wider range of disease invasion, requiring more thorough lymph node dissection, thereby increasing the risk of damaging the parathyroid gland or its blood supply.

Inclusion Criteria:

• All cases were the first to undergo thyroidectomy surgery.
• All clinical data and research materials of the cases are complete.
• All cases underwent thyroid function examination before and after surgery.
• All cases underwent preoperative thyroid and neck lymph node examinations by the Ultrasound Department of Shandong Provincial Hospital.

Exclusion Criteria:

• Except for cases of recurrence.
• Cases with incomplete clinical data and research materials are excluded.
• Cases that have not undergone thyroid function tests before and after surgery are excluded.
• Excluding cases of secondary surgery.
• Cases that have not undergone thyroid and neck lymph node examinations by the Ultrasound Department of Shandong Provincial Hospital before surgery are excluded.

This study collected data from patients who underwent thyroidectomy surgery at the Breast and Thyroid Surgery Department of Shandong Provincial Hospital from January 2020 to December 2023. All patients included in the study had complete clinical data and research materials, with approximately 2000 participants.

The IPD are not publicly available due to privacy and ethical restrictions.