Effect of approach side during anterior cervical discectomy and fusion on the incidence of recurrent laryngeal nerve injury

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>This retrospective study was designed to determine whether side of approach during instrumented, one- or two-level primary anterior cervical discectomy and fusion (ACDF) affects the incidence of recurrent laryngeal nerve (RLN) injury diagnosed by observation of the vocal cords (OVC).</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Records of all patients who underwent one- or two-level instrumented primary ACDF (418 patients) between January 1995 and February 2004 were reviewed. Data collected from these charts included surgeon, patient demographics, preoperative diagnosis, side of exposure, number of vertebral levels fused, and presence of RLN injury diagnosed by OVC after referral for persistent dysphonia. Time from surgery to OVC for patients with right-sided exposures was not statistically different from that for patients with left-sided exposures. Of 418 patients, 278 (66.5%) had right-sided exposures and 140 (33.5%) had left-sided exposures. Eight RLN injuries (1.9%) were noted—five in patients with right-sided exposures (1.8%) and three in patients with left-sided exposures (2.1%). The difference between right- and left-sided injury rates was shown to be nonsignificant using Fisher exact tests.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Results indicate that, given the study’s sample size, side of approach during instrumented, one- or two-level primary ACDF has no significant effect on RLN injury incidence in patients with persistent dysphonia referred for OVC. The definitive answer regarding the true incidence of RLN injury relative to approach side awaits a prospective study with preoperative, immediate postoperative, and periodic OVC in a large, homogeneous population with sufficient numbers of patients with right- and left-sided approaches.</jats:p></jats:sec>

Variations in the Course of the Cervical Vagus Nerve on Thyroid Ultrasonography

“…The incidence of the recurrent laryngeal nerve branch ranged from Ͻ1% to 6% for thyroidectomy, from Ͻ1% to 8% for carotid endarterectomy, and from 1.3% to 2.6% for anterior cervical spine surgery. 4,[9][10][11][12] The recurrent laryngeal fibers are medially placed in the vagal trunk. 3,13 For anterior variation, the VN was superficial and medial to the CCA, and nerve injury may occur during dissection by a diathermy burn or mechanical stretching during carotid endarterectomy.…”

Prevention and management of dysphonia during anterior cervical spine surgery

“…RLN palsy accounts for most of these cases, and although SLN injury may occur, findings can be subtle. The reported incidence of RLN injury in a combined series of more than 3,000 cases in which a head and neck surgeon was not involved in the exposure was between 1.9% and 5% 7, 11–13. One study has shown a similar rate of temporary RLN palsy, but recovery occurred in many of these (Table I).…”

Maintaining endotracheal tube cuff pressure at 20 mm Hg to prevent dysphagia after anterior cervical spine surgery; protocol of a double-blind randomised controlled trial

“…Structures trapped between the retractor and the endotracheal tube cuff, like the recurrent laryngeal nerve, may be compromised. In patients who were treated with anterior cervical discectomy and fusion, the incidence of recurrent laryngeal nerve injury is about 2%, irrespective of the side of approach [3]. Consequently, dysphagia, hoarseness, and sore throat may occur.…”