What type of fracture involves the base of the first metacarpal due to direct impact?

The fracture that involves the base of the first metacarpal due to a direct impact is identified as Bennett's fracture. This type of fracture is characterized by a fracture of the base of the first metacarpal bone, which can often result from trauma, such as hitting an object or from a fall on an outstretched hand. A significant feature of Bennett's fracture is that it often causes an intra-articular fracture, which means it affects the joint surface, leading to challenges in management and rehabilitation if not appropriately addressed.

The mechanism of injury and the anatomical location make Bennett's fracture distinct from other types of fractures. In contrast, a Smith's fracture typically involves a fracture of the distal radius with palmar angulation; a Colles fracture also involves the distal radius but is characterized by dorsal angulation; and a scaphoid fracture occurs at the wrist and typically involves the scaphoid bone rather than the metacarpal bones. Understanding these nuances helps to accurately identify the type of fracture based on the mechanism and location of injury.