Demonstrations of anatomy : being a guide to the dissection of the human body / by G.V. Ellis.

  • George Viner Ellis
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: Demonstrations of anatomy : being a guide to the dissection of the human body / by G.V. Ellis. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

    171/790 (page 157)
    outer and inner parts. | Some fibres from aryte- noid carti- lage to vocal cord. Relations. The thyroarytenoid muscle (fig. 41) extends from the thyroid ^n^°ary to the arytenoid cartilage ; it is thick below, but thin and expanded muscle above. The muscle arises from the thyroid cartilage near the middle line, for about the lower half of its depth, and from the crico-thyroid membrane. The fibres are directed backwards with consists of different inclinations :—The external (4) ascend somewhat and are inserted into the outer border of the arytenoid car- tilage. The internal fibres (s) are horizontal, and form a thick bundle which is inserted into the margins of the vocal process and the lower part of the outer surface of that car- tilage. A few of the deepest fibres of the muscle pass from the outer surface of the vocal process of the arytenoid carti- lage to be inserted into the true vocal cord. The outer surface of the muscleis coveredbythe thyroid cartilage ; and the inner sur- face rests on the vocal cords, and on the ventricle and pouch of the larynx. Action. Thethyro-arytenoid draws forwards the arytenoid cartilage, and causes the cricoid to move forwards and downwards, thus opposing the crico-thyroid muscle, and shortening the vocal cords. It also moves inwards the fore part of the arytenoid cartilage with the true vocal cord, so as to place the latter in the position necessary for vocalization. The short fibres passing from the arytenoid cartilage to the vocal cord will tighten the fore part, and relax the Joinder part of the ■ cord. The thyro-epiglottidean muscle is a thin layer which varies Thyro- much in its development in different bodies. Its fibres arise from j^^)iiiji3C]e the thyroid cartilage in conjunction with the outer part of the thyro- arytenoid, and are directed upwards, covering the outer surface of the saccule of the larynx, to be inserted into the margin of the Use. * Internal muscles of the larynx. 1. Crico-thyroid detached. 2. Posterior orico-arytenoid. 3. Lateral crico-arytenoid. 4. Thyro-arytenoid, superficial part. 5. Depressor of the epiglottis, consisting of fibres of the aryteno- epiglottidean muscle and others given off from the thyro-arytonoid. 6. Thyro- hyoid, cut. 8. Deep part of thyro-arytenoid.