Classification

Type I:      Undisplaced; risk of avascular necrosis (AVN) <10%


Type II:     Displaced fracture with subtalar subluxation or dislocation; risk of AVN >40%


Type III:    Displaced fracture with subtalar and ankle dislocation; risk of AVN >90%


Type IV:    Type III + variants (eg, dislocation of talonavicular joint); risk of AVN 100%

Explanation

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Figures

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Reference(s)

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