Metacarpal Fracture broken hand boxer fracture
The long bones of the hand are called the metacarpals.  There are 5 metacarpals -- one for each finger.  An injury to the hand can break one or more of the metacarpals.  This is known as a metacarpal fracture.
Metacarpal fractures usually result from a traumatic blow to the hand.  Metacarpal fractures may involve the head, neck, shaft, or base of the metacarpal.  Fractures of the 5th metacarpal neck are especially common.  They typically occur with punching a hard object and are known as boxer fractures.
Metacarpal fractures are diagnosed based on a history, physical exam, and x-rays.  Patients may report punching a wall or another traumatic blow to the hand.
Upon physical exam, the hand may be bruised and swollen.  The broken bone will, of course, be tender to push on.  There may be a deformity at the fracture site.  The knuckle associated with the broken metacarpal may be less prominent.  The fingers are inspected to look for rotational deformities.
X-rays are important not only to confirm that the hand is broken, but to evaluate the fracture.  Fractures may be non-displaced (just a crack) or displaced.  They may involve the cartilage in the joints (intra-articular).  They may be angulated (bent at the fracture site).
Non-displaced metacarpal fractures can be treated without surgery.  A cast or splint is applied to immobilize the affected fingers and limit motion across the fracture site.  This prevents the broken fragment from displacing (moving out of place) and allows the fracture to heal.  The fracture takes 4 to 6 weeks to heal.
If the metacarpal fracture is displaced or angulated, it must be reduced.  This means that the fracture is pushed back into alignment.  If a stable reduction can be obtained, a cast or splint is applied to hold the fragments in place and allow the fracture to heal.
x-rays of a boxer fracture
Boxer Fracture Closed Reduction
5th metacarpal fracture
If the fracture is too displaced or unstable, especially if it involves the joint surface, an adequate reduction may not be possible to maintain without surgery.  Surgery sometimes involves pushing the fracture fragments back into place and then drilling a pin through the skin and across the fracture site to hold the fragments in position.  This is known as percutaneous pinning or closed reduction-internal fixation (CRIF).  Pins are usually removed in the office in 3 to 5 weeks.
Occasionally, the fracture cannot be successfully reduced without making an incision and exposing the bone.  This is known as open reduction-internal fixation (ORIF).  Screws or plates may be used to fix the fragments in place.  These are generally not removed.
metacarpals
phalanges
carpals
radius ulna
head
neck
shaft
base
boxer fracture
1st
2nd
3rd
4th
5th
finger rotated outward
finger rotated inward
x-rays of boxer fracture before and after reduction
percutaneous pinning