What term describes the movement of ribs in a flail segment that is opposite to the rest of the chest cavity during breathing?

The term that describes the movement of ribs in a flail segment that is opposite to the rest of the chest cavity during breathing is known as paradoxical motion. This condition occurs when a segment of the rib cage experiences a disassociation from the normal movement pattern during the respiratory cycle. In a healthy individual, the ribs expand outwards and upwards during inhalation and return inward during exhalation. However, in the case of a flail segment—often resulting from rib fractures—the affected area moves inward when the rest of the chest expands, and moves outward when the chest contracts during respiration. This abnormal movement can severely affect ventilation and compromise respiratory efficiency, indicating a significant clinical condition that requires immediate medical attention.

Understanding paradoxical motion is essential for health professionals since it can be a sign of serious underlying trauma or respiratory distress, thus guiding their assessment and intervention strategies.