MTP6.17 Preventing laryngeal nerve palsy during thyroidectomies – a non-systematic review of the surgical anatomy literature

Background Recurrent laryngeal nerve palsy is an established morbidity in thyroidectomy with various risk factors and mechanisms of injury. Various anatomical landmarks are used to identify the recurrent laryngeal nerve intraoperatively with differing levels of prevalence and significance. Variations of the nerve can complicate the procedure for many surgeons, increasing the risk of injury. Preventative methods can be used to mitigate against palsy, although considerable controversy exists as to the most effective method. Methods A literature search was carried out using PubMed, to identify relevant papers using Boolean operators, such as AND and OR. Key words were utilised, for example, “variations”, “landmarks” and “preventative methods”. Results Repeat goiter operations and malignancy are the main risk factors, with traction and thermal injuries being the most common mechanisms of nerve injury. The tracheooesphageal groove and inferior thyroid artery have a higher variability in their relationship to the nerve, whereas the Zuckerkandl tubercle and Berry’s ligament are highly consistent. Extralaryngeal branching poses a high risk of palsy due to their high prevalence. Intraoperative visualisation is the current gold standard for preserving the nerve, but certain injuries are only detected by intraoperative neuromonitoring. However, there are no statistically significant differences in palsy rates between either method. Conclusions The Zuckerkandl tubercle and Berry’s ligament are effective landmarks in thyroidectomy to identify the nerve. Intraoperative visualisation is still the main method to preserve nerve integrity but intraoperative neuromonitoring may play a role as an adjunct. Further studies with larger sample sizes are needed to reduce biases.