fracture_metacarpal
Table of Contents
fractures of the metacarpal
introduction
- ~30-40% of all fractures involving the hand are metacarpal fractures
fracture neck 5th metacarpal
- 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
Mx in the ED
- 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.
fracture of the metacarpal head
- 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
fracture of the shaft of the metacarpal
- 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
fracture base of 1st metacarpal
Bennett's fracture
- 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
Rolando fracture
- as for Bennett's fracture but intra-articular comminution is present
fracture base 5th metacarpal
"reverse Bennett's" fracture
- 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
extra-articular fracture
- usually due to direct blow to ulnar border of the hand
carpometacarpal dislocations
- 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
metacarpophalangeal dislocations
- may be reduced in the ED and referred to plastic surgery for definitive management
fracture_metacarpal.txt · Last modified: 2013/07/03 03:46 by 127.0.0.1