Bennett fracture dislocation

A Bennett fracture-dislocation is a fracture of the thumb resultant of forced abduction of the first metacarpal. Defined as an intra-articular two-part fracture of the base of the first metacarpal bone.

  • two piece fracture dislocation of the base of the thumb metacarpal 
  • intra-articular extension 
  • dorsolateral dislocation
  • small fragment of 1st metacarpal continues to articulate with trapezium
  • lateral retraction of the first metacarpal shaft by abductor pollicis longus

When an intra-articular fracture of the 1st metacarpal is comminuted, producing at least three parts, it is referred to as a Rolando fracture which has a worse prognosis.

The fracture requires open reduction and fixation if there is significant displacement (>3 mm). Clearly, this is also influenced by the age and profession/hobbies of the patient, as a step in the articular surface will predispose to secondary osteoarthritis. If malunion or non-union occurs, a pseudoarthrosis may result.

It is named after Edward Hallaran Bennett (1837-1907), a surgeon from Dublin, Ireland.

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Article information

rID: 984
Synonyms or Alternate Spellings:
  • Bennett's fracture dislocation

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