The paradoxical motion of the chest wall is the hallmark of this condition,
with the flail segment paradoxically moving inward with inspiration and
outward with expiration.
139.The answer is d.(Rosen, pp 370-374.)Owing to its lack of bony pro-
tection, the neck is especially vulnerable to severe, life-threatening injuries.
Neck trauma is caused by three major mechanisms, including penetrating,
blunt, and strangulation, which can affect the airway, digestive tract, vascu-
lar, and neurologic systems. The neck is divided into three zones, as seen in
the picture below. Zone I extends superiorly from the sternal notch and
clavicles to the cricoid cartilage. Injuries to this region can affect both neck
and mediastinal structures. Zone II is the area between the cricoid cartilage
and the angle of the mandible. Zone III extends from the angle of the
mandible to the base of the skull. Zone I and III injuries typically pose a
greater challenge to manage than Zone II injuries because Zones I and III are
much less exposed than Zone II. Generally, Zone II injuries are taken
directly to the operating room for surgical exploration. Injuries in Zones I
and III may be taken to the operating room or managed conservatively using
a combination of angiography, bronchoscopy, esophagoscopy, and CT scanning.
Trauma Answers 157(Reproduced, with permission, from Doherty GM,Way LW.Current Surgical Diagnosis &
Treatment. New York, NY: McGraw-Hill, 2006: 210.)