see also:

• plastic surgery
• the injured hand
• fractures and dislocations of the fingers

• ~30-40% of all fractures involving the hand are metacarpal fractures

• this is one of the most common fracture presentations to the ED
• accounts for ~10% of all hand fractures
• commonly called “boxer's fracture” as this is usually caused by striking a solid object with a closed fist such as an untrained person's attempt to punch someone or an object using a “round-house” action
• trained boxers generally use a “proper punch” with most of the impact passing through the stronger 2nd and 3rd metacarpals rather than the 5th metacarpal and thus generally do not sustain these fractures
• less commonly, the neck of the 4th MC may be fractured as well as or instead of the 5th MC neck
• these fractures remain unstable despite any attempts to reduce any angulation in the ED and as such this is not usually worthwhile attempting

• Xray and diagnosis
• any patients with compound injuries, particularly injuries over the MCP joint area should be considered at serious risk for infection particularly if there is a chance they could have been caused by impact with a recipient's tooth. Such injuries generally should be managed with iv antibiotics with coverage for oral flora and referred to plastic surgery that day for wash out in theatre.
• patients with closed injuries may be placed in a volar slab and referred to plastic surgery within a week for consideration of ORIF, although some patients may elect to accept the minor deformity of loss of the 5th knuckle to avoid having the problems of K-wires interfering with their work, and risk of osteomyelitis.

• much less common than fracture of the neck of the metacarpal
• usually due to direct trauma over the metacarpal head or ligamentous avulsion
• displaced fractures generally require referral to plastic surgery for ORIF

• may be caused by axial loading, direct blow or torsional loading producing either transverse, oblique or spiral fractures
• remember to clinically examine for rotational deformity by flexing fingers and looking for mis-direction of the involved finger
• displaced fractures with more than 3-4mm displacement or more than 10deg angulation, or any rotational deformity usually require reduction and thus referral to plastic surgery for ORIF
• undisplaced or minimally displaced fractures may be managed with plaster slab or perhaps supportive stocking and elevation

• caused by axial loading on the thumb
• intra-articular fracture subluxation of the thumb carpometacarpal (CMC) joint
• early diagnosis and referral to plastic surgery (usually for ORIF) is important to prevent long term morbidity

• as for Bennett's fracture but intra-articular comminution is present

• analagous to the Bennett's fracture except involving the 5th CMC jt
• usually due to axial load
• most mobile of the 4 ulnar CMC jts and thus most prone to arthrosis from articular incongruity
• thus refer to plastic surgery for possible ORIF

• usually due to direct blow to ulnar border of the hand

• may occur with or without fracture and usually require strong forces and thus there is a high risk of other injuries which should be sought
• may be reduced in the ED and referred to plastic surgery for definitive management

• may be reduced in the ED and referred to plastic surgery for definitive management