Mechanism
The Bennett fracture is an oblique intraarticular metacarpal fracture dislocation, caused by an axial force directed against the partially flexed metacarpal. This type of compression along the metacarpal bone is often sustained when a person punches a hard object, such as the skull or tibia of an opponent, or a wall. It can also occur as a result of a fall onto the thumb. This is a common injury sustained from bike falls, as the thumb is generally extended while around the handle bars. It is also a common injury in car crashes, especially into fixed objects, from the driver holding the steering wheel during impact. The hand moves forward, while the steering wheel rim hyperextends the thumb. Some authors have recently made an assertion against popular belief that the APL tendon is not a deforming force on the Bennett fracture. Treatment
Though these fractures commonly appear quite subtle or even inconsequential on radiographs, they can result in severe long-term dysfunction of the hand if left untreated. In his original description of this type of fracture in 1882, Bennett stressed the need for early diagnosis and treatment in order to prevent loss of function of the thumb CMC joint, which is critical to the overall function of the hand. In the most minor cases of Bennett fracture, there may be only small avulsion fractures, relatively little joint instability, and minimal subluxation of the CMC joint (less than 1 mm).
Therefore, the goal of treatment of Bennett fracture should be to achieve the most precise reduction possible, whether by the CRPP or the ORIF approach. Nomenclature
The Bennett fracture is named after Edward Hallaran Bennett, Professor of Surgery (1837–1907) at Trinity College of the University of Dublin, who described it in 1882. Bennett said his fracture "passed obliquely across the base of the bone, detaching the greater part of the articular surface, and the separated fragment was very large and the deformity that resulted there-from seemed more a dorsal subluxation of the first metacarpal". See also
Rolando fracture
Boxers fracture
Gamekeepers thumb

References
External links
Bennett fracture at Who Named It?