The platysma muscle in neck dissection

Although the platysma muscle is usually preserved during neck dissection, r emoval of this muscle is generally considered inconsequential. The present case report shows that sacrifice of the cervical branch of the facial nerve innervating this muscle and removal of the platysma's upper portion impair s the caudal retraction and eversion of the ipsilateral half of the lower l ip in grinning or laughing.