Objective: To explore the safety, feasibility and clinical effect of the endoscopic thyroid surgery through sutureless intermuscular approach (SISA). 
Methods: The clinical data of 20 patients undergoing thyroid surgery from January 2018 to October 2018 were retrospectively analyzed. All patients underwent endoscopic SISA thyroidectomy by the same surgeon, and it was performed by exposing the thyroid through opening the underlying intermuscular spaces between the strap muscles of the neck.
Results: Operations were successfully completed in all the 20 patients, without any intraoperative conversion to other procedures. Three patients with thyroid adenoma underwent unilateral major thyroid lobectomy, of the 13 patients with nodular goiter, 5 cases underwent unilateral major thyroid lobectomy and 8 cases underwent bilateral major thyroid lobectomy, and 4 patients with primary hyperthyroidism underwent bilateral major thyroid lobectomy. The operative time was (65±23.3) min, the intraoperative blood loss was (5.5±1.9) mL; the external branch of superior laryngeal nerve was exposed in 26 sides (81.2%, 26/32), and the recurrent laryngeal nerve was exposed in 30 sides (93.7%, 30/32). No postoperative complication occurred, and the volume of drainage on postoperative day (POD) 1 was (54.5±32.46) mL, the VAS pain score on POD 1 was 0 1, and the length of postoperative hospital stay was 2–3 d. Followed-up was conducted for 3 months after surgery, neck paresthesia and neck skin traction phenomenon during swallowing was found in one case, but no recurrence occurred and the cosmetic results were favorable.
Conclusion: The endoscopic SISA thyroid surgery is safe and feasible, with the advantages of no need of cutting the linea alba cervicalis, avoidance of suturing, mild pain, easy exposure of nerves, and insignificant postoperative neck adhesion.