Correct answer:

Paradoxical respiration; pneumothorax; penetration of the lung; haemothorax; cardiac tamponade due to laceration of the heart; large vessel damage. Serious damage can also result from blunt (crush) injuries that do not penetrate the chest; thus, a main bronchus or the aorta may be ruptured, the lung contused and papillary muscles of the heart or the coronary arteries may be damaged.