Metacarpal Fracture

Background

A metacarpal fracture results from either blunt trauma directly to the metacarpal, or from a torsional force applied to the associated finger. The fracture pattern reflects the injury mechanism in most cases. There are many elements that are important to consider when treating these, including the patient’s activity level, medical history and specifics as they relate to the fracture itself, such as rotation, angulation and shortening.

Causes

These fractures usually result from blunt force or torsional trauma. Higher energy mechanisms are also possible, such as injuries from gunshots, nailguns, and crush injuries. Fractures of the 5th metacarpal neck and carpometacarpal fracture dislocations can also occur when the patient punches a hard object.

Symptoms

Metacarpal fractures cause pain, tenderness, and swelling over the affected metacarpal. If the fracture is displaced, there may be a visible deformity such as angulation or malrotation called scissoring. Characteristic bruising in the palm can also be seen.

Diagnosis

The injured hand is assessed. Range of motion is typically diminished, in conjunction with bruising and swelling. X Rays are critical to make the diagnosis and help guide treatment.

Treatment

Minimally displaced fractures can be braced or casted. Displaced fractures may require surgery which usually entails lining the bone up properly, and placing a plate and screws to stabilize the fracture while it heals. Closed manipulation (without incision) and placement of temporary pins is also an established technique. Depending on the fracture pattern, placement of a device such as an intramedullary nail or cannulated headless screw can be considered. Open fractures usually require surgical intervention.

Combination of lag screws and cerclage wires to treat 4th and 5th metacarpal shaft fractures.

Plate and screws to treat a second metacarpal shaft fracture.

Minimally-invasive internal fixation technique for a fifth metacarpal neck fracture in a young athlete.