The effect of strap muscle transection on voice and swallowing changes after thyroidectomy in patients without laryngeal nerve injury

Abstract

Introduction Voice and swallowing symptoms are frequently reported after thyroidectomy even without laryngeal nerve injury. We aimed to evaluate the effect of strap muscle transection on voice and swallowing outcome after thyroidectomy. Methods Group 1 (G1) consisted of 17 patients who had their strap muscles transected during thyroidectomy and group 2 (G2) consisted of 17 patients who had their strap muscles preserved during thyroidectomy. None of the patients had laryngeal nerve injury. Voice impairment scores (VIS) and swallowing impairment scores (SIS) were obtained preoperatively and at 1 week and 1, 3 and 6 months postoperatively. Pre- and postoperative vocal cord examinations were performed for all patients. The external branch of the superior laryngeal nerve (EBSLN) was evaluated by intraoperative cricothyroid muscle electromyography. Results There was no significant difference in VIS and SIS between the two groups. At postoperative week 1, the VIS and SIS for each group were above preoperative values (G1: p = 0.005 and p = 0.035; G2: p = 0.031, p = 0.346, for VIS and SIS respectively). The VIS and SIS scores at 6 months postoperatively were significantly lower than those of the first week postoperatively (G1: p = 0.04 and p = 0.001; G2: p = 0.022 and p = 0.034 respectively) and similar to preoperative values (G1: p = 0.924 and p = 0.086; G2: p = 0.822 and p = 0.187 respectively). Conclusion Although voice and swallowing complaints increased in the early postoperative period even without recurrent laryngeal nerve and EBSLN injuries, these symptoms are not related with the strap muscle transection.