46.1 Description

External fixation is a treatment option for distal radius fractures, which involves placement of threaded pins distal and proximal to the fracture with a connecting external frame.

46.2 Key Principles

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  External fixation can provide stabilization of distal radius fractures by ligamentotaxis, ¹ which is the principle of soft tissue tension across a joint to realign fracture components.

  
  
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  External fixation may be applied with or without internal fixation, depending on fracture variables (open or closed, degree of comminution, and stability of fragment fixation) when ligamentotaxis alone does not restore fracture alignment.

  
  
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  Optimal PA and lateral radiographic parameters to guide treatment include radial inclination of 22 degrees, volar tilt of 11 degrees, and ulnar variance similar to unaffected wrist.

  
  
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  Central placement of pins, each through two cortices, into the index metacarpal and radial shaft provides secure fixation for the external fixator frame.

46.3 Expectations

For unstable fractures following attempted closed reduction, external fixation with or without internal fixation can assist in the maintenance of acceptable fracture alignment, with the goal of preventing displacement and malunion and achieving painless and functional wrist range of motion.

46.4 Indications

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  Unstable fractures (extra and/or intraarticular) in which optimal radiographic parameters are not achieved with closed reduction and/or internal fixation.

  
  
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  As a supplement to internal fixation in preventing fracture collapse due to significant comminution.

  
  
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  Open/contaminated fractures.

  
  
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  Patients who must bear weight on the wrist for ambulation.

46.5 Contraindications

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  Stable fractures (minimally displaced or where internal fixation is preferred).

  
  
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  Volar or dorsal marginal fractures requiring an internal buttress.

  
  
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  Patient comorbidities (age and medical issues) not permitting surgical intervention.

  
  
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  Noncompliant patients.

  
  
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  Associated fractures of index, long metacarpals, or radial shaft, which may interfere with proper pin placement.

46.6 Special Considerations

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  CT scans can better define intra-articular fracture morphology and degree of comminution to assist in decision-making for use of external fixation.

  
  
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  Intraoperative fluoroscopy can provide significant guidance regarding the adequacy of fracture reduction and pin placement.

With improved internal fixation techniques, including the option of internal bridge plating, the use of external fixation for distal radius fractures has become less common. ^{2 , 3}