During the rapid trauma assessment of the victim of a boating accident, you note that part of the patient's chest wall is moving in the direction opposite that of the rest of the chest. What is the cause of this movement?
1) Two or more ribs are broken at two or more places, causing a floating segment of ribs.
2) The patient's collarbone is broken, causing the chest to move paradoxically.
3) The patient is having severe difficulty breathing, causing retractions.
4) Cardiac tamponade restricts the movement of the chest.
