Occipital condylar fractures - classification by Anderson and Montesano
The Anderson and Montesano classification was published in 1988. It divides occipital condylar fractures into three types according to their morphology and mechanisms of injury.
| Type | Description | Mechanism | Note |
|---|---|---|---|
| Type I | comminuted fracture without or with minimal displacement of fragments | axial load | the ipsilateral alar ligament may be injured, stability is preserved by the contralateral alar ligament and the tectorial membrane, bilateral lesions may be unstable |
| Type II | linear fracture as a part of a basioccipital fracture, fracture line extends from the foramen magnum to the skull base | extension | stability is preserved by intact alar ligaments and tectorial membrane |
| Type III | avulsion fracture of the condyle near the alar ligament | rotation and lateroflexion | injury to the tectorial membrane and the contalateral alar ligament may cause instability |
References:
1. Anderson PA, Montesano PX. Morphology and treatment of occipital condyle fractures. Spine. 1988 Jul;13(7):731–6.
2. Leone A, Cerase A, Colosimo C, Lauro L, Puca A, Marano P. Occipital Condylar Fractures: A Review1. Radiology. 2000 Sep 1;216(3):635–44.
3. Malham GM, Ackland HM, Jones R, Williamson OD, Varma DK. Occipital condyle fractures: incidence and clinical follow-up at a level 1 trauma centre. Emerg Radiol. 2009 Jul 1;16(4):291–7.
Updated 23/8/2013 12:12 by Lambert