The outcomes of parathyroid gland autotransplantation during thyroid surgery: a systematic review, meta-analysis and trial sequential analysis

Purpose Thyroidectomy is the treatment of choice for malignant thyroid diseases as well as for benign conditions who cannot be treated medically. The most common complication following thyroidectomy is hypocalcaemia and hypoparathyroidism that usually results from accidental damage or removal of one or more parathyroid glands. Parathyroid gland autotransplantation has been one of the most common intraoperative strategies applied to tackle this problem. The aim of this study is to assess whether parathyroid auto trasnplantation is associated with a decrease in postoperative hypoparathyroidism following thyroidectomy. Methods We conducted a thorough systematic review and meta-analysis of relevant studies published up to February 2024 in MEDLINE, Scopus, Embase and Cochrane Library databases. We compared the incidence of postoperative hypoparathyroidism between the group of patients who underwent autotransplantation and the patients were the parathyroid glands were preserved in situ. A trial sequential analysis was performed subsequently to confirm the findings. Results Eighteen studies fulfilled all the inclusion criteria and were ultimately included in our study. The total number of patients was 8,182 with 4,029 receiving parathyroid gland autotransplantation. Autotransplantation was associated with a higher incidence of immediate (within 24 h) and transient hypoparathyroidism (RR 1.58, 1.45-1.73, CI 95%, p < 0.00 and RR 1.60, 1.47-1.76, CI 95%, p < 0.001, respectively). However, it did not affect the rate of permanent postoperative hypoparathyroidism (RR 0.85, 0.51-1.41, CI 95%, p = 0.54). The subsequent trial sequential analysis confirmed these findings. Conclusion Parathyroid autotransplantation does not lead to a decrease in the rate of permanent post-thyroidectomy hypoparathyroidism. The most important factor to decrease its incidence remains the accurate identification and preservation of the parathyroid glands intraoperatively.