Platysma Muscles, Lateral View

Description

Seen in lateral profile, the superficial platysma spreads as a thin muscular sheet over the anterolateral neck, running inferiorly from the inferior border of the mandible toward the superficial fascia of the upper thorax and clavicular region. Deep to it, the sternocleidomastoid forms the dominant oblique strap from the mastoid process to the manubrium and medial clavicle, separating the anterior cervical region from the posterior triangle. The mandibular angle, mastoid process, clavicle, and upper sternum act as hard landmarks that help orient the soft tissue relationships. Clean anatomy. Because the platysma is a muscle of facial expression that also tenses cervical skin, its course and thinness matter in both trauma and elective surgery, where it frequently defines the depth of subcutaneous dissection. In a lateral neck approach, appreciating how the platysma overlies the external jugular vein and the investing layer of deep cervical fascia helps reduce iatrogenic bleeding and guides flap elevation, while the sternocleidomastoid remains the key surface landmark for locating the carotid sheath deeper and more anterior. This view also supports teaching of cervical nerve blocks, where the superficial cervical plexus emerges at the posterior border of the sternocleidomastoid (Erb point) and anesthesia must be delivered superficial to the fascia but deep to the platysma. Suitable for head and neck anatomy labs, otolaryngology and plastic surgery teaching files, and procedural guides covering cervical incisions, rhytidectomy planes, and platysmal band management. Medical publishers can pair it with surface anatomy callouts for mastoid, mandible, and clavicular landmarks in lateral patient positioning. Anatomical accuracy verified by SciePro's Medical Advisory Board.