Answer:
The platysma is a thin broad sheet of muscle investing the anteromedial aspect of the neck. Its originates from the fascia over the upper parts of the pectoralis major and deltoid muscles. It inserts into the skin and subcutaneous tissues of the lower face. The dominant vascular pedicle is the submental artery which is a branch of the facial artery. It also receives blood supply from the postauricular, occipital, superior thyroid, and transverse cervical artery. For coverage of the lip and chin a vertical flap is based on the submental artery and a skin paddle can be elevated as well (approximately 10 x 15 cm).