MORPHOLOGICAL STUDY OF MUSCLE SPINDLES IN ARYTENOID MUSCLE OF HUMAN LARYNX

Abstract

The existence of the muscle spindles in the arytenoid muscle of the human larynx was confirmed. The morphological features were described in detail using light- and electron-microscopes. The specimens were obtained from three larynges. The seven muscle spindles were found in all of the three specimens. The diameter at the equator was 85 to 115μm., and the number of the intrafusal muscle fibers was two to five. The two types of the intrafusal muscle fibers were differentiated, the nuclear bag type and nuclear chain type. As the specific type of the muscle spindle, the monofibrillar type and compound type were also found. The dimension of the muscle spindle in the arytenoid muscle was relatively small in comparison with that in other skeletal muscle.