This is one of the most complex regions of the body, it consists of the skull the bony skeleton of the head it protects the brain, organs of special senses and the cranial parts of the respiratory and digestive tracts, it also provides attachments for the muscles of the head and neck. The neck is that part of the body that supports the head and serves as a passageway between the head, brain and the body; the skeleton of the neck is made up the seven cervical vertebrae posteriorly and the hyoid bone and thyroid cartilage anteriorly, it is defined as the region lying between the inferior border of the mandible and the superior border of the clavicle.