Extrafusal fibers were oxidative type 1 and glycolytic type II
A and II X.
Intrafusal fibers (myosin spindle) were identified by the
presence of tonic and neonatal myosin.
Due to presence of these fibers, it prove that interarytenoid
muscle are phenotypically similar to skeletal muscle in the
limb.
Function of interarytenoid muscle is to hold the vocal cord in
closed position. Interarytenoid muscle from one side attach to
interarytenoid muscle on other side.
Interarytenoid muscle is located between arytenoid cartilage in
the midline at the back of glottis.