Table 2.
Classification of hangman’s fracture
| Authors | Year of publication | Basis of classification | Type of hangman’s fracture | Description |
|---|---|---|---|---|
| Williams [44] | 1975 | Mechanism of injury | Type one (true hangman’s fractures) | Caused by extension and distraction |
| Type two (axis pedicle fractures) | Caused by extension and compression | |||
| Seljeskog and Chou [32] | 1976 | X-ray studies | Type one | Isolated C2 laminar-pedicle fractures |
| Type two | Typical hangman’s fracture-dislocation without subluxation | |||
| Type three | Typical hangman’s fracture-dislocation With subluxation (Minimal: less than 4 mm; Moderate: more than 4 mm) | |||
| Pepin and Hawkin [27] | 1981 | X-ray Evaluation | Type one (nondisplaced fracture) | Only involved the posterior part |
| Type two (displaced fracture) | The posterior element and the body of C2 were included | |||
| Francis and Fielding [13] | 1981 | Displacement,agulation, and ligamentous in stability | Francis Grade | C2-C3 Displacement C2-C3 Angulations (°) |
| I | < 3.5 <11 | |||
| II | < 3.5 >11 | |||
| III | >3.5 < 0.5 (vertebral width) <11 |
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| IV | >3.5 < 0.5 (vertebral width) >11 |
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| V | Disc disruption | |||
| Effendi et al. [11] | 1981 | Radiographic signs and the clinical course | Type I | Single hairline fractures of the pedicle of axis |
| Type II | Displacement of the anterior fragment with an abnormal disc below the axis (flexion, extension, spondylolisthesis) | |||
| Type III | Displacement of the anterior element with the body of the axis in the flexed position and the facet joints at C2-3 are dislocated and locked | |||
| Levine and Edwards [20] | 1985 | Mechanism of fractures | Type I | Axial loading and hyperextension |
| Type II | Hyperextension-axial loading force associated with severe flexion | |||
| Type IIa | Flexion-distraction, mild or no displacement but very severe angulation | |||
| Type III | Flexion-compression | |||
| Levine [19] | 1998 | Type Ia | Minimal translation and little or no angulation elongation of the C2 body | |
| Levine and Rhyne [21] | 1991 | Subtypes of Type III | Bipedicular fractures with bilateral facet dislocation Unilateral facet injuries or dislocations bound to a contralateral neural arch fracture Bilateral facet dislocation combined with bilaminar factures of C2 |