A COTA is working with a client who punched a wall after an argument. The client presents with inflammation and pain in the right fourth and fifth metacarpals. What type of fracture does this client most likely have?

• A. Bennett's fracture
• B. Colles fracture
• C. Boxer's fracture
• D. Kienbock's fracture

Answer: (C)

When a closed fist punches a hard object, the force travels through the metacarpals and most often stresses the neck of the fifth metacarpal. This narrow, vulnerable area is where the bone is most likely to crack when the hand is clenched and the punch lands, producing the classic boxer's fracture. The fifth metacarpal is the one that forms the prominent knuckle on the little finger side, so it bears the brunt of the impact and typically presents with swelling and tenderness over the distal metacarpal neck.

This fits the scenario of punching a wall and having inflammation and pain around the fourth and fifth metacarpals—the most common injury from this mechanism is a fracture at the neck of the fifth metacarpal, hence the boxer's fracture.

To contrast, Bennett's fracture is a fracture at the base of the first metacarpal near the thumb joint; Colles fracture is a distal radius fracture from falling on an outstretched hand; Kienbock's fracture refers to avascular necrosis of the lunate, not a simple metacarpal fracture.