Electromyographic control of a hands-free electrolarynx using neck strap muscles

Abstract

Three individuals with total laryngectomy were studied for their ability to control a hands-free electrolarynx (EL) using neck surface electromyography (EMG) for on/off and pitch modulation. The laryngectomy surgery of participants was modified to preserve neck strap musculature for EMG-based EL control (EMG-EL), with muscles on one side maintaining natural innervation and those on the other side receiving a transferred recurrent laryngeal nerve (RLN). EMG from each side of the neck controlled the EMG-EL across a day of unstructured practice followed by a day of formal training, including EMG biofeedback. Using either control source, participants spoke intelligibly and fluently with the EMG-EL before formal training. This good initial performance did not consistently improve across testing for either control source in terms of voice timing, speech intelligibility, fluency, and intonation of interrogative versus declarative sentences. Neck strap muscles have activation patterns capable of simple alaryngeal voice control without requiring RLN transfer. Learning outcomes: The reader will better understand (1) functionality of the hands-free electrolarynx (2) modification of laryngectomy surgery to preserve neck strap musculature and (3) performance of hands-free electrolarynx with different control sources.