(See also Overview of Fractures.)
Metacarpal neck fractures are common. They cause pain, swelling, tenderness, and sometimes deformity. Rotational deformity 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 antibiotics.
Diagnosis
Treatment
If patients have any wounds, particularly linear punctures, near the metacarpophalangeal joint, they should be specifically questioned about whether they punched someone in the mouth. If they did, contamination with human oral flora is possible, and measures to prevent infection (eg, wound exploration and cleaning, prophylactic antibiotics) are often required.
Treatment of a metacarpal neck fracture is with a splint (eg, an ulnar gutter splint for fractures of the 4th or 5th metacarpal), usually for at least a few weeks. Whether reduction is needed before the splint is applied depends on the fracture.
Reduction is not necessary for dorsal or volar angulation of
Reduction is necessary for
Usually, closed reduction is possible. Use of a hematoma block or an ulnar nerve block can help reduce the pain during reduction.
After the splint is removed, patients can gradually begin range-of-motion exercises.
Key Points
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Metacarpal neck fractures cause pain, swelling, tenderness, and sometimes deformity (eg, rotational deformity).
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Take anteroposterior, lateral, and oblique x-rays.
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If patients have wounds near the metacarpophalangeal joint, ask them whether they punched someone in the mouth; if they did, take measures to prevent infection (eg, prophylactic antibiotics).
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Treat a metacarpal neck fracture with a splint; if angulation is significant or if rotational deformity is present, reduce the fracture first, usually using closed reduction.
