The Instrument of Voice: The “True” Vocal Cord or Vocal Fold? Andy Hall, Richard Cobb, Karan Kapoor, Romana Kuchai, and Guri Sandhu, London, UK In seeking a common language within laryngology, there is a need to explore consistency in our terminology. The interchange- able use of the terms “vocal fold” and “vocal cord” among otolaryngologists worldwide is an area of debate in existence for almost 300 years. Both are used synonymously in modern anatomical texts 1 to describe the paired structure that stretches between the anteri- or commissure and the arytenoid cartilage. There are two distinct regions to this structure that differ in both anatomical form and function. From the anterior commissure to the tip of the vocal process of the arytenoid cartilage is the membranous or mus- culomembranous portion, which has primarily a phonatory role. The cartilaginous portion includes the vocal process, and the medial aspect of the body of the arytenoid cartilage. This defines the lateral limits of the posterior glottis, through which maximal airflow takes place during breathing. The National Cancer Institute in conjunction with the Amer- ican Joint Committee on Cancer (AJCC) and American Academy of Otolaryngology—Head and Neck Surgery use the term “vocal cord” throughout the TNM grading system for glottic cancer 2 and, as such, this term is used with some consistency within the area of head and neck cancer worldwide. The posterior commissure is usually interpreted as lying between the arytenoids at the level of the glottis; however, the AJCC description is problematic as its definition of the poste- rior commissure is potentially inclusive of both the supraglottic structures (arytenoids) and the glottis itself. Apart from malignant pathology, there is more widespread use of the term “vocal fold” among laryngologists in similar con- sensus documents. 3 The etymological origin and evolution of the nomenclature appear to arise from a debate as to the theory of voice devel- oping through laryngeal dissection. The discrepancy arose from the understanding of classifying the larynx as a form of “wind,” “brass,” or “string” instrument. Galen’s main theory of phona- tion originally detailed that the glottis resembled the reeds found in auloi (oboe-like instrument). In contrast, Dodart in 1700 de- scribed the glottis as more akin to the lips of a horn player. 4 In 1741, the French anatomist Antoine Ferrein reviewed and modified the theory of phonation in “the formation of the human voice.” 5 This led to his creation of a hypothesis whereby the larynx is considered to be a combination of wind and string instrument. Apart from Leonardo da Vinci’s early experimen- tation, Ferrein was the first to study phonation experimentally by forcing air through the detached larynxes of various animals. 6 According to Ferrein, these “lips of the glottis” form two true “vocal cords” or plicœ vocals (Latin); and from this point, the term was used. He believed that sounds arose solely through the vibration of these cords. The vibration itself was produced by the stream of exhaled air. In a musical analogy, the air was un- derstood to act as the violin bow itself, while the “cords” acted as the strings of the violin. The counter argument was promoted separately by Henry Detrochet and Francois Magendie. Both individuals recom- mended dropping “cords” in favor of the term “folds” because of the observation that the vocal folds of the larynx did not act as a string instrument but acted more like the vibrating bands of wind instruments. 7 The British English Corpus allows the analysis of metadata by lexicographers to display modern developments in the English language. This has demonstrated an increasing misappropria- tion of “vocal chord” in modern writing to the extent that it has become the predominantly used term. Recent lexicographical anal- ysis demonstrates that “vocal chord” is used in 49% of cases in comparison with the historically correct term “cord.” 8 The development of laryngoscopy and microscopy has nat- urally led to far greater understanding of the mechanism of phonation itself and the microanatomy of the mucosal wave. 9 As such, we contend that the term “fold” reflects best our modern anatomical and physiological understanding. To use the term “cord” etymologically suggests several strands, twisted or woven together. Conceptually, the term “fold” neatly represents the pli- ability of the loose “outer” mucosal layers over the stiffer underlying vocal ligament and muscle. As such, it is the better term to detail dynamic pathologies, ie, paresis or waveform ab- normalities. To differentiate between the two anatomical sites, the terms membranous (or musculomembranous) vocal fold and cartilaginous vocal fold should be used. For teaching purposes, the clarity of expression in this term is also advantageous. Language within medicine evolves in keeping with our understanding and the time seems right to consign the term “cord” to history. REFERENCES 1. Standring S. Gray’s Anatomy—The Anatomical Basis of Clinical Practice,. 41st ed. NewYork, NY: 2015. 2. Sobin L, Gospodarowicz MK, Wittekind C. Head and neck tumours. In: TNM Classification of Malignant Tumours. 7th ed. New York, NY: Springer; 2009:22–62. 3. Koufman JA, Aviv JE, Casiano RR, et al. Laryngo-pharyngeal reflux: position statement of the Committee on Speech, Voice, and Swallowing Disorders of the American Academy of Otolaryngology—Head and Neck Surgery. Otolaryngol Head Neck Surg. 2002;127:32–35. From the National Centre for Airway Reconstruction, Charing Cross Hospital, London, UK. Address correspondence and reprint requests to Andy Hall, National Centre for Airway Reconstruction, Charing Cross Hospital, London, UK. E-mail: andyhall07@googlemail.com Journal ofVoice, Vol. ■■, No. ■■, pp. ■■-■■ 0892-1997 © 2016 Published by Elsevier Inc. on behalf of The Voice Foundation. http://dx.doi.org/10.1016/j.jvoice.2016.02.008 ARTICLE IN PRESS