Classification and mechanism of subaxial cervical spine injuries.pptx

Classification and mechanism of subaxial cervical spine innjuries

1. Classification and Mechanism of Subaxial Cervical Spine Injuries Department of Neurosurgery Dr RE Anto 21/02/2024

2. Contents Introduction Anatomy Mechanisms Classification Stability References

3. Introduction The subaxial spine is from C3 – C7 Distinct from C1 + C2 so it's viewed as a different entity

4. Osseous Anatomy Uncovertebral joint Joint of Lushka Lateral projections of the body Medial to the VA Facet joints Sagittal orientation at 30-40 degrees Spinous processes Bifid C7 prominent

5. Facet Joint Zygapophyseal joints Formed by the articular processes of adjacent vertebrae Synovial gliding joints Sagittal orientation 30 – 45 degrees

6. Lateral Mass Anatomy Medial border Lateral edge of lamina Lateral border Superior/Inferior borders Facets VA is anterior to the medial border of the lateral mass, enters at C6 4 quadrants of the lateral mass with the supero -lateral mass being safe

7. Ligamentous Anatomy Anterior ALL, PLL, Intervertebral disc Posterior Nuchal ligaments Supraspinous Interspinous Ligamentum Flavum and the facet joint capsules

8. Vascular Anatomy Vertebral artery Originates from subclavian a. Enters the spine at C6 foramen At C2 turns posterior and lateral Forms Basilar artery higher up intradural Foramen transversarium Gradually moves anteriorly and medially from C6 – C2.

9. Mechanisms of injury Hyperflexion Axial compression Hyperextension Rotatory

10. Hyperflexion Distraction creates tensile forces in posterior column Can result in compression of body (anterior column) Most commonly results from MVA and falls

11. Axial Compression Result from axial loading Commonly from diving, football, MVA Injury pattern depends on initial head position May create burst, wedge or compression fractures

12. Hyperextension Impaction of posterior arches and facet compression causing many types of fractures: Lamina Spinous processes Pedicles With distraction get disruption of ALL Evaluate carefully for stability CENTRAL CORD SYNDROME

13. Classification Systems 1982 : Allen and Ferguson 1986 : Harris et al OCNA 1996 : Stauffer and MacMillan Fractures 2005 : Cervical Spine Injury Severity Score (CSISS) 2007 : SLIC (S ubaxial cervical spine injury classification) 2013 : AO Spine Classification

14. Allen and Ferguson Classification First mechanistic classification for the subaxial cervical spine 6 mechanisms of injury Compression flexion Vertical compression Distraction flexion Compression extension Distraction extension Lateral flexion

15. Allen and Ferguson Classification

16. Harris Classification Published in 1986. 7 mechanisms of injury Flexion (5 subgroups) Flexion rotation Extension-rotation Vertical compression (2 subgroups) Hyperextension (7 subgroups) Lateral flexion Diverse / Imprecisely understood mechanisms (2 subgroups)

17. Cervical Spine Injury Severity Score (CSISS) Published in 2006 by Moore. Based on the four-column model Anterior + Posterior + Left + Right Pillars Scoring system from 0-5 in each of the four columns, depending on severity.

18. Cervical Spine Injury Severity Score (CSISS) Score: <5: Non operative 5 – 7: Grey >7: Surgical

19. Subaxial Cervical Spine Injury Classification (SLIC) Published in 2007 by Vaccaro et al. 3 components Injury morphology Disco-ligamentous complex (DLC) Neurological status

20. Subaxial Cervical Spine Injury Classification (SLIC)

21. Injury Morphology Compression injury A visible loss of height through part of an entire vertebral body, or disruption through an endplate. Distraction injury Includes both flexion and extension injury Evidence of anatomic dissociation in the vertical axis Rotation/translation injury, There must be “horizontal displacement of 1 part of the subaxial cervical spine with respect to the other”

22. DLC Abnormal widening of the anterior disc space Abnormal facet alignment High signal intensity seen horizontally through a disc involving the nucleus and anulus on a T2 sagittal MRI Widening of the space between 2 spinous processes Increased water content as seen on T2-weighted MRI and interpreted as a sign of oedema should be classified as indeterminate

23. Neurological Status An important indicator of the severity of spinal column injury Significant neurological injury infers a significant force of impact and potential instability to the cervical spine Neurological status may be the single most influential predictor of treatment

24. AO Spine Classification AOSpine Knowledge Forum developed the spinal trauma classification in 2013 3 major types A: Compression injuries B: Tension band injuries C: Translation injuries F: Facet injuries

25. Type A – Compression Injuries

26. Type B – Tension Band Injuries

27. Type C – Translation Injuries

28. Type F – Facet Injuries

29. White and Panjabi Spinal Stability

30. References Allen BL Jr, Ferguson RL, et al. A mechanistic classification of closed, indirect fractures and dislocations of the lower cervical spine. Spine (Phila Pa 1976). 1982 Jan-Feb;7(1):1-27. Harris JH, Edeiken -Monroe B, Kopaniky DR. A practical classification of acute cervical spine injuries. The Orthopedic clinics of North America. 1986 Jan;17(1):15–30. Moore T a, Vaccaro AR, Anderson P a. Classification of lower cervical spine injuries. Spine. 2006 May 15;31(11 Suppl ):S37–43 Vaccaro AR, Hulbert RJ, Patel A a , Fisher C, Dvorak M, Lehman R a, et al. The subaxial cervical spine injury classification system: a novel approach to recognize the importance of morphology, neurology, and integrity of the disco-ligamentous complex. Spine. 2007 Oct 1;32(21):2365–74 Vaccaro AR, Koerner JD, Radcliff KE, et al. AOSpine subaxial cervical spine injury classification system. Eur Spine J. 2016;25:2173–2184. doi:10.1007/s00586-015-3831-3 White AA, Panjabi MM. The Problem of Clinical Instability in the Human Spine: A Systematic Approach. In: Clinical Biomechanics of the Spine. 2nd ed. Philadelphia: J.B. Lippincott; 1990:277–378

31. Thank you