1982 Volume 85 Issue 8 Pages 951-956
A study was made of the mechanical properties of the canine intrinsic laryngeal muscles; thyroarytenoid, cricothyroid, posterior cricoarytenoid, and lateral cricoarytenoid. These muscles were stimulated electrically with constant voltage stimulation of 1 Volt.
The contraction time was found to differ between the relatively fast group (thyroarytenoid, 14 msec; lateral cricoarytenoid, 21 msec) and the relatively slow group (cricothyroid, 40 msec; posterior cricoarytenoid, 45 msec). The fusion frequency was also found to differ between the two groups, i. e. higher in the former (95Hz and 90Hz, respectively) and lower in the latter (40Hz and 45Hz, respectively). There was a certain correlation between the contraction time and the fusion frequency; the shorter the contraction time was, the higher was the fusion frequency.
The mechanical properties of the laryngeal muscles were compared with the movement and biomechanics of the glottis induced by stimulation of the laryngeal nerve branch distributing to each intrinsic laryngeal muscle. The results indicated that the laryngeal movements and biomechanics, especially the glottic pressure, the size of the glottic chink and the adduction-abduction tension were affected significantly by the mechanical properties of the intrinsic laryngeal muscles and other anatomical structures such as the so-called elsetic recoil.
