zone 2

Penetrating neck trauma is classically divided into three zones based on anatomic landmarks, which historically guided management decisions:

- Zone 1: Extends from the clavicles/sternal notch to the cricoid cartilage. Contains great vessels (proximal carotid arteries, subclavian vessels, brachiocephalic vessels), trachea, esophagus, thoracic duct, and lung apices. Injuries here are associated with the highest mortality due to difficult surgical access and potential for major vascular/mediastinal injury; often requires angiography and possibly sternotomy.

- Zone 2: Extends from the cricoid cartilage to the angle of the mandible. Contains the carotid arteries, jugular veins, larynx, trachea, esophagus, and vagus nerve. This zone is the most commonly injured due to its length and relative lack of bony protection. Because it is easily accessible surgically, traditional management favored mandatory surgical exploration for penetrating injuries violating the platysma; however, modern practice has shifted toward selective management based on hard vs. soft signs of vascular/aerodigestive injury, using CT angiography to guide the decision between observation, further imaging, or operative exploration.

- Zone 3: Extends from the angle of the mandible to the base of the skull. Contains distal carotid and vertebral arteries, salivary and pharyngeal structures. Surgical access is difficult due to the mandible; injuries often require angiographic embolization or endovascular management rather than open surgery.

Clinical significance: Hard signs of vascular injury (pulsatile bleeding, expanding hematoma, bruit/thrill, absent distal pulses, signs of cerebral ischemia) or aerodigestive injury (air bubbling from wound, hemoptysis, dysphagia, subcutaneous emphysema, stridor) mandate immediate surgical exploration regardless of zone. In hemodynamically stable patients without hard signs, CT angiography is the initial diagnostic modality of choice across all zones, reflecting the shift away from strict zone-based mandatory exploration protocols ("no-zone" approach) in many trauma centers.