Оцінка рівня нестабільності ушкоджень, класифікованих за AOSpine Subaxial Cervical Spine Injury Classification System

Abstract

Background. The main criteria for determining surgery strategy in patients with traumatic subaxial cervical injury are as follows: the type and degree of damage to the osteo-ligamentous structures of cervical spine that determines the level of instability; the value of spinal cord compression; the state of the sagittal profile. The aim of this study was to assess the degree of instability in different types of cervical spine injuries according to AOSpine Subaxial Cervical Spine Injury Classification System. Materials and methods. We performed a retrospective analysis of Х-ray, computed tomography and magnetic resonance imaging data of 168 patients with traumatic injury of subaxial cervical spine. All of them were hospitalized at the Department of Spinal Cord Pathology of the Romodanov Neurosurgery Institute of National Academy of Medical Sciences of Ukraine 2008–2018. We assessed the degree of instability using the Cervical Spine Injury Severity Score and determined the type of damage according to the AOSpine Subaxial Cervical Spine Injury Classification System. Results. We found that the median rate of instability increases progressively with increasing severity of injury type. The widest range of instability values is observed in the compression damage: from 6 points (95% confidence interval (CI): 4.76–6.84) in A1 type to 11 points (95% CI: 9.48–11.81) in A4. For A2 and A3 types, we registered 7 (95% CI: 6.68–7.53) and 8 points (95% CI: 7.97–9.01), respectively. A smaller range of values characterizes flexion-extension injuries. The median progressively increases from B1 type — 13 points (95% CI: 12.4–13.92) to B3 type — 15.5 points (95% CI: 14.5–16.35). The value for B2 is intermediate and is 15 points (95% CI: 13.59–15.52). We registered maximum values in flexion-extension injuries — 18 points, for both B2 and B3 types. C type has the highest level of instability — 17 points (95% CI: 16.58–17.86) and a quite wide range of estimated values: from 13 to 20 points. Conclusions. The general trend is an increase in the level of instability in the range from A1 to C injury subtypes, but even A1 type in some cases are quite unstable and require surgery. In contrast to the classical views, type A injuries are often accompanied by da-mage to the facet joints, which must also be taken into account when determining the individual treatment.