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Motion Capture Technology Can Evaluate Extrinsic Laryngeal Muscle Movement Patterns

by Linda Kossoff •

CLINICAL QUESTION

Can motion capture (MoCap) technology distinguish extrinsic laryngeal muscle (ELM) tension and hyperfunction between individuals with and without primary muscle tension dysphonia (pMTD)?

BOTTOM LINE

Results show the feasibility and reliability of MoCap in studying ELM kinematics.

BACKGROUND: Patients with pMTD experience a range of symptoms, including vocal strain and vocal tract discomfort. Some patients complain about the feel of their voice despite a normal sound quality. Although ELM tension and hyperfunction are often implicated as the cause, well-vetted physiological metrics to study ELM tension and hyperfunction are lacking.

STUDY DESIGN: Prospective cohort study.

SETTING: Department of Computer Science, Erik Jonsson School of Engineering and Computer Science, University of Texas at Dallas, Richardson.

SYNOPSIS: Researchers divided 30 participants into two groups: 15 with a formal diagnosis of pMTD and 15 controls. For all participants, 16 markers were placed on different anatomical landmarks on the chin and anterior neck. Movements across these regions were tracked during four voice and speech tasks using two three-dimensional cameras. Movement displacement and variability were determined based on 16 key points and 53 edges. Twelve videos were obtained for each participant. Significance of ELM edge movement displacement and variability across the 53 edges between groups for each of the tasks were statistically analyzed. The findings showed more movement variability but similar movement displacements across the 53 edges in the pMTD group as compared with the control group, and greater movement displacement in the thyrohyoid space in the pMTD group. Results demonstrated the feasibility and strong reliability of MoCap as a method to study ELM movement patterns. Intra- and inter-reliability measures were strong, and there were movement patterns using MoCap that could differentiate between groups with and without pMTD. Study limitations included the limits of MoCap itself, given variations in neck skin characteristics such as edema and scarring.

CITATION: Hogue S, Guo X, Morrison RA, et al. Use of motion capture technology to study extrinsic laryngeal muscle tension and hyperfunction. Laryngoscope. 2023;133:3472–3481.