The classifications of subaxial cervical spine traumatic injuries. Part 6. Ben L. Allen biomechanical classification




traumatic injury, Allen-Ferguson classification, cervical spine, subaxial level, morphology, biomechanics


Traumatic injuries of subaxial cervical spine are characterized by a wide range of possible pathomorphological changes that depend not only on the direction and intensity of the traumatic force impact, but also on the initial position of cervical spine at the moment of exposure.

One of the most detailed classifications of cervical spine traumatic injuries, in which the integrated approach to assessing the type of injury considering the mechanism of injury is used, is the system developed by Ben L. Allen and published with co-authors in 1982. It is also known as the Allen-Ferguson classification and despite long history of existence, still has not lost its relevance.

In the classification when characterizing the type of traumatic injury, not only visually detected signs, but also inevitably accompanying changes are given.

In total, 6 types of damage were classified: compression-flexion, vertical compression, distraction-flexion, compression-extension, distraction-extension and lateral-flexion, which were divided into stages depending on the severity of pathomorphological changes. The authors of the classification note a pronounced correlation between the nature of damage to anatomical structures and neurological disorders in all patterns of damage.

When writing this review, a detailed analysis of the original publication was carried out, highlighting the basic biomechanical aspects that underlie the classification and still have not lost their relevance . It is noted that the schematic images of damages found in modern literature often do not correspond to the description proposed by Ben L. Allen et al., Therefore, when preparing the illustrative material, we relied solely on the data of the original article.

Along with the description of morphology, for each type and stage of injury, modern data on possible methods of treatment, both conservative and surgical are given.

The complex analysis suggests that the classification developed by Ben L. Allen is a convenient tool for assessing pathomorphological changes and allows choosing the optimal method of treating the patients in each specific clinical situation.

Author Biographies

Oleksii S. Nekhlopochyn, Romodanov Neurosurgery Institute, Kyiv

Spine Surgery Department

Ievgenii I.  Slynko, Romodanov Neurosurgery Institute, Kyiv

Spine Surgery Department

Vadim V. Verbov, Romodanov Neurosurgery Institute, Kyiv

Restorative Neurosurgery Department


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How to Cite

Nekhlopochyn, O. S., Slynko, I. I., & Verbov, V. V. (2021). The classifications of subaxial cervical spine traumatic injuries. Part 6. Ben L. Allen biomechanical classification. Ukrainian Neurosurgical Journal, 27(3), 3–16.



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