ObjectiveTo investigate the risk factors of accidental parathyroidectomy following thyroid surgery.MethodsData of patients who accepted at least total thyroidectomy in the Center for Diagnosis and Treatment of Thyroid and Parathyroid Diseases between January 2013 and June 2016 was collected retrospectively. According to the appearance or non-appearance of parathyroid gland in the specimens after pathologic examination, the patients were divided into accidental parathyroidectomy group and non-accidental parathyroidectomy group. Clinical data was collected for comparison between the two groups. The risk factors of accidental parathyroidectomy were indentified with univariate analysis and multivariate analysis.ResultsA total of 983 patients, 50 patients in the accidental parathyroidectomy group and 933 patients in the non-accidental parathyroidectomy group, were included in the study. Incidence of temporary hypoparathyroidism was 66.0% (33/50) in the accidental parathyroidectomy group and 36.2% (338/933) in the non-accidental parathyroidectomy group, there was significant difference between the two groups (χ2=19.903, P<0.05). Incidence of permanent hypoparathyroidism was 2.0% (1/50) in the accidental parathyroidectomy group and 0.4% (4/933) in the non-accidental parathyroidectomy group, and there was no significant difference between the two groups (χ2=2.315, P=0.128). Univariate analysis showed that bilateral central lymph nodes dissection (P=0.004) and the number of identified parathyroid glands ≤2 (P=0.002) were risk factors of accidental parathyroidectomy. Multivariate analysis showed that bilateral central lymph nodes dissection [OR=2.553, 95% CI was (1.236, 5.277), P=0.011] and the number of identified parathyroid glands ≤2 [OR=2.819, 95% CI was (1.423, 5.581), P=0.003] were independent risk factors of accidental parathyroidectomy.ConclusionsAfter careful consideration of the possible risks and benefits, bilateral central lymph nodes dissection should be performed rationally. Thyroid surgeons should improve the ability of identification of parathyroid gland to reduce the incidence of accidental parathyroidectomy.