Certified Surgical First Assistant (CSFA) Practice Test

Which metacarpal is most commonly fractured in a "boxer's fracture"?

1. Second metacarpal

2. Third metacarpal

3. Fourth metacarpal

4. Fifth metacarpal

The correct answer is: Fifth metacarpal

The fifth metacarpal is most commonly fractured in what is known as a "boxer's fracture." This type of fracture typically occurs when an individual punches a hard object, often leading to a break in the neck of the fifth metacarpal, which is the bone that supports the little finger. The mechanism of injury is usually associated with a forceful impact, causing the bone to fracture in a location where it is more vulnerable. The fifth metacarpal is subjected to significant stress during such an action, especially with repeated trauma or improper technique. In contrast, while other metacarpals can be fractured, they are less frequently associated with this specific type of injury. The second and third metacarpals are located more centrally in the hand and are typically more stable, while the fourth metacarpal has some anatomical similarities to the fifth but does not sustain fractures as commonly due to punching. This anatomical and functional context makes the fifth metacarpal distinctively prone to fractures in boxing scenarios.