The anterior triangle occupies the side of the neck in front of sternomastoid muscle. Each triangle presents boundaries in front:
Boundaries of anterior triangle are:
Anteriorly by the median plane.
Posteriorly by the sternocleidomastoid.
Superiorly by the base of the mandible and by a line joining the angle of
mandible to the mastoid process.
The apex of the triangle lies above the manubrium sterni
Anterior median line of the neck extending from symphysis menti to suprasternal notch.
The midline of the neck
Midline of the neck up to the sternoclavicular joint
Posterior border of thyroid gland