Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P97. The risk of recurrent laryngeal nerve injury with laterality of approach in anterior cervical discectomy and fusion procedures: a randomized, prospective study over 10 years

Abstract

BACKGROUND CONTEXT Recurrent laryngeal nerve (RLN) injury is a well known, but potentially devastating injury after anterior cervical discectomy and fusion (ACDF) procedures. Although RLN injury is most often transient in nature, there are the associated clinical consequences of dysphonia, impaired phonation or cough reflex, airway obstruction, hoarseness, vocal fatigue, and in some cases, tracheotomy. The incidence of RLN injury in the literature ranges from 0.07% to 5.1%. There has been debate regarding the risk of RLN injury in relation to laterality of approach, with proponents of each left and right sided approaches. There are numerous papers reviewing the complication, but there is no large-scale, randomized prospective single surgeon, single study investigating the correlation of laterality of approach to the risk of recurrent laryngeal nerve injury. PURPOSE To determine if the side of approach in anterior cervical discectomy and fusion is associated with increased risk of recurrent laryngeal nerve injury. STUDY DESIGN/SETTING A fellowship trained spine surgeon prospectively performed ACDFs between the years of 2003-2012. Side of approach was chosen based on contralateral to side of symptoms (ie right sided radicular symptoms, patient received a left-sided approach). Patients were monitored postoperatively for development of recurrent laryngeal nerve palsy symptoms. Patients found to have signs of recurrent laryngeal nerve injury were sent to ENT for confirmation and monitored for recovery. PATIENT SAMPLE A total of 411 patients undergoing anterior cervical decompression procedures over 10years in central Pennsylvania. OUTCOME MEASURES Symptoms of recurrent laryngeal nerve injury (dysphonia, dysphagia). METHODS Retrospecive analysis of prospectively collected data over 10years. RESULTS A total of 411 ACDFs were performed during the 10-year period. 190 right sided and 221 left sided procedures were done. The incidence of recurrent laryngeal nerve injury was 14 (13 primary procedures and 1 revision). Seven nerve injuries were in a right sided approach and 7 were in a left sided approach. The risk of injury was 3.18% in a left sided approach and 3.70% in a right sided approach with a p-value of 0.7723 indicating that there is no significant difference between the sides of the approach. CONCLUSIONS Our study's analysis showed that there was a 3.18% chance of RLN with a left-sided approach compared to a 3.70% chance of RLN injury with a right-sided approach (p-value: .7723), indicating that there is no significant difference in RLN injury between the sides of approach. Although there is usually spontaneous resolution of hoarseness, it is important to remember that patients with a vocal cord paresis may be asymptomatic, and patients with symptomatic dysphonia may have no vocal cord paresis. Our data represents the first randomized prospective single surgeon study of risk of symptomatic RLN injury from side of approach. There was no significant difference noted between the side of approach and the risk of recurrent laryngeal nerve palsy, and it is recommended that the surgeon choose an approach based on his or or her comfort and clinical judgement.