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Anderson and D'Alonzo classification of odontoid process fracture

The Anderson and D'Alonzo classification is the most commonly used classification of fractures of the odontoid process of C2.

Classification

  • type I
    • rare
    • fracture of the upper part of the odontoid peg
    • above the level of the transverse band of the cruciform ligament
    • usually considered stable
  • type II
    • most common
    • fracture at the base of the odontoid
    • below the level of the transverse band of the cruciform ligament
    • unstable
    • high risk of non-union
  • type III
    • through the odontoid and into the lateral masses of C2
    • relatively stable if not excessively displaced
    • best prognosis for healing because of the larger surface area of the fracture

Another classification system is the Roy-Camille classification.

Fractures
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Article information

rID: 41604
Synonyms or Alternate Spellings:
  • Anderson and D'Alonzo classification of odontoid process fractures

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Cases and figures

  • Figure 1
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  • Odontoid Fracture...
    Case 1: type II
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  • Case 2: type III
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