What is a Bennett fracture?

Bennett fracture is a fracture involving the base of the metacarpal bone of the thumb.

Bennett fracture is usually caused by axial force on the thumb accompanied by radial deflection and rotational forces. This causes the fracture line to extend from the base of the metacarpal bone into the joint. In addition to the typical history of trauma, localized pain, swelling, and limited motion, imaging studies such as X-rays are essential for a definitive diagnosis. Careful analysis of the displacement of the fracture on X-rays and the extent of joint involvement.

Mild displacement can be treated conservatively, such as plaster fixation. However, for obvious displacement or instability fractures, surgical treatment is often required to restore the flatness of the joint surface and stability of the fracture. Early interphalangeal joint motion gradually transitions to functional exercises such as flexion and extension of the thumb and palmar opposition to maximize the restoration of thumb function.