injuries poisoning
Metacarpal Neck Fractures
Introduction
Metacarpal neck fractures usually result from an axial load (eg, from punching with a clenched fist). (See also Overview of Fractures .) This discussion pertains to fractures of the metacarpal bones other than the thumb metacarpal. Fractures of the neck of metacarpals 2 through 5 are common. They cause pain, swelling, tenderness, and sometimes deformity. Rotational deformity due to a fracture in the hand may occur. The 5th metacarpal is most commonly injured by punching (boxer's fracture). When these fractures result from punching someone in the mouth, human oral flora may contaminate the wound, sometimes causing infection. Patients with fight bites require Normally, when the proximal interphalangeal joints are flexed to 90°, lines from the distal phalanges converge at a point on the proximal carpal bones. Deviation of one of these lines suggests a metacarpal fracture. 