Which ribs are most commonly fractured due to external or internal force?

• A. 1 to 3
• B. 3 to 10
• C. 11 to 12
• D. 5 to 7

Answer: (B)

Ribs that are most commonly fractured due to external or internal force are typically the ones situated in the mid-section of the ribcage, particularly the 3rd to 10th ribs. These ribs are less protected by the surrounding musculature compared to ribs higher up, which are shielded by the clavicle and the shoulder girdle, and lower ribs, which tend to be protected by the abdominal organs.

The middle ribs have a larger range of motion due to breathing, making them more susceptible to fractures during events such as falls, accidents, or sports injuries. The anatomical structure of these ribs provides less support compared to the first ribs, which are more robust and anchored, and the lower ribs, which are not as frequently subjected to trauma since they are generally surrounded by muscle and organs.

Furthermore, the mechanism of injury for fractured ribs commonly involves direct impact or compression, which more often affects the ribs in the middle section rather than the first few or the last couple. This heightens the likelihood that ribs 3 to 10 will sustain fractures from various forces encountered in accidents or trauma situations.