Indirect Estimates of Jaw Muscle Tension in Children With Suspected Hypertonia, Children With Suspected Hypotonia, and Matched Controls

Abstract

Purpose In this study, the authors compared indirect estimates of jaw-muscle tension in children with suspected muscle-tone abnormalities with age- and gender-matched controls. Method Jaw movement and muscle activation were measured in children (ages 3 years, 11 months, to 10 years) with suspected muscle-tone abnormalities (Down syndrome or spastic cerebral palsy; n = 10) and controls (n = 11). Two measures were used to infer jaw tension: a kinematic index of mass-normalized stiffness and electromechanical delay (EMD). The kinematic index used video-based kinematics to obtain the slope of the peak velocity-displacement relationship. The EMD was derived from the interval between the onset of suprahyoid muscle activity and the onset of jaw depression. Results Neither measure differentiated the groups. The kinematic index revealed differences between stressed and unstressed syllables in 3-syllable productions by the participants with cerebral palsy and controls, but not in 2-syllable productions by the participants with Down syndrome and controls. Conclusion This preliminary investigation included the novel application of 2 measures to infer the jaw-muscle tension of children with suspected tone abnormalities. Although the results do not support the hypothesis that suspected muscle-tone abnormalities affect jaw movement sufficiently to influence speech production, considerations for interpreting the findings include methodological limitations and possible compensatory muscle coactivation.

Data-Driven Subclassification of Speech Sound Disorders in Preschool Children

“…The identification of this motor speech group using nonprimary features of SSD, such as speech movement variability, supports the finding that direct measures of the primary features of developmental speech disorders are not sufficient to differentiate clinically distinct populations (Connaghan & Moore, 2013). For instance, participants in both groups scored similarly on the measures resulting from the PEPPER analyses of the conversational speech samples (e.g., percentage consonants correct: Group A, 72%; Group B, 70.3%), demonstrating that children in Group B would be difficult to identify using only conventional measures of speech competence.…”

Estimates of the prevalence of speech and motor speech disorders in adolescents with Down syndrome

“…Physiologic findings suggest that individuals with DS have limited tongue movement during vowel production and as a result, a reduction in acoustic vowel space, articulatory working space, and articulatory speed (Bunton & Leddy, 2011). But some researchers suggest that the anomalous muscle tone in individuals with DS does not influence the speech musculature sufficiently to alter speech production (Connaghan & Moore, 2013).…”

Clinical and Anatomical Requirements and Indications for Using a Novel Multifunctional Gnatic Device

“…local and general factors [1]. The consequence of muscle hypertonia is the activation of anaerobic glycolysis, accompanied by the accumulation of lactic acid, which in turn irritates pain receptors, causing aggravation of pain symptoms [2,11]. The emergence of a painful effect is a stressor agent, which leads to a more forced muscle spasm [10], against the background of the production of adrenaline.…”