1. Upper Cervical Spine Fractures Daniel Gelb, MD Created January 2006

2. Upper Cervical Spine Fractures Epidemiology Anatomy Radiology Common Injuries Management Issues

3. Upper Cervical Spine Fractures Epidemiology –Cause MVC42% Fall20% GSW16% –Gender Male81% Female19%

4. Etiology of Spinal Cord Injury by Age Source: National Spinal Cord Injury Statistical Center, University of Alabama at Birmingham, 2004 Annual Statistical Report, June, 2004

5. Upper Cervical Spine Fractures Epidemiology –Level of Education To 8th Grade: 10% 9th to 11th: 26% High School: 48% College: 16%

6. Source: National Spinal Cord Injury Statistical Center, University of Alabama at Birmingham, 2004 Annual Statistical Report, June, 2004 Employment Status

7. Source: National Spinal Cord Injury Statistical Center, University of Alabama at Birmingham, 2004 Annual Statistical Report, June, 2004 Percent Employed

8. Upper Cervical Anatomy

9. Biomechanically Specialized –Support of “large” Cranial mass –Large range of motion Flexion/extension Axial rotation Unique osteological characteristics

10. C1 - Atlas No body 2 articular pillars –Flat articular surface –Vertebral artery foramen 2 arches –Anterior –Posterior Vertebral artery groove

11. Anatomy – The Atlas Transition zone between head and c-spine Important anatomical points –Superior articular processes allow flex/ext –Inferior articular processes are important for rotation –Notch for vertebral artery is a common fracture site

12. C2 Anatomy Dens –Embriological C1 body –Base poorly vascularized –Osteoporotic Flat C1-2 joints Vertebral artery foramena –Inferomedial to superolateral

13. Anatomy – The Axis Important transition point for forces within the c-spine Important anatomical points –Superior and inferior articular processes are “offset” in the AP direction- due to different functions at each articulation –Pars interarticularis- due to this transition is a frequent fracture site –Odontoid process- the “pivot” for rotation

14. Anatomy – The Ligaments Allow for the wide ROM of upper C-spine while maintaining stability Classified according to location with respect to vertebral canal –Internal: Tectorial membrane Cruciate ligament – including transverse ligament Alar and apical ligaments –External Anterior and posterior atlanto-occipital membranes Anterior and posterior atlanto-axial membranes Articular capsules and ligamentum nuchae

15. AtlantoAxial Anatomy Tectorial Membrane

16. AtlantoAxial Anatomy occiput C1 C2 Tranverse Ligament C1-C2 joint Alar Ligament

17. AtlantoAxial Anatomy Transverse Ligament Facet for Occipital Condyle

19. AtlantoAxial Anatomy Vertebral Artery

20. Radiographic Evaluation

21. Plain Radiographic Evaluation Lateral View Prevertebral Swelling Soft Tissue Shadow <6mm at C2 Concave/Flat Predental space < 3mm Atlanto-Occipital Joint Congruence Radiographic Lines* Open Mouth AP Distraction C1-2 Symmetry

22. Radiographic Diagnosis – Screening Lines Powers’s Ratio Harris’s lines

23. Radiographic Lines Harris et al, Am J Radiol, 1994 Basion-Dental Interval (BDI) Basion to Tip of Dens <12 mm in 95% >12 mm ABNORMAL Basion-Axial Interval (BAI) Basion to Posterior Dens -4-12 mm in 98% >12 mm Anterior Subluxation >4 mm Posterior Subluxation Harris’ Lines

24. Radiographic Lines BC/OA –>1 considered abnormal Limited Usefulness Positive only in Anterior Translational injuries False Negative with pure distraction Powers et al, Neurosurg, 1979 Powers’ Ratio

25. Radiographic Diagnosis CT Scan Same rules as with plain films Better visualization of craniocervical junction Subluxation Focal hematomas Occ condyle fx Dens fx

26. Radiographic Diagnosis MRI Increased Signal Intensity in : Occ-C1Joint C1-2 Joint Spinal Cord Craniocervical ligaments Prevertebral soft tissues Warner et al, Emerg Radiol, 1996 Dickman et al, J Neurosurg, 1991

27. Upper Cervical Spine Fractures Common Injuries –Occipital Condyle Fracture –Occipital Cervical Dislocation –C1 ring injuries –Odontoid Fracture –Hangman’s Fracture

28. Occipital Condyle Fracture Type I Impaction Fx Type II Extension of basilar skull fx Type III ALAR LIG AVULSION Anderson,SPINE 1988 Tuli, NEUROSURGERY, 1997

29. OccipitoAtlantal Dissociation (OAD) Commonly Fatal Present 6-20% of post mortem studies –Alker et al, 1978 –Bucholz & Burkhead,1979 –Adams et al, 1992 50% missed injury rate 1/3 Neurological Worsening –Davis et al, 1993

30. OccipitoAtlantal Dissociation (OAD) Symptoms/Findings –Wallenberg Syndrome Lower Cranial nerve deficits Horner’s syndrome Cerebellar ataxia Cruciate paralysis Contralateral loss of pain and temperature

31. Occipital Cervical Dissociation Treatment Emergency Room Collar/sandbag Halo vest Definitive Posterior occipital cervical fusion

33. Transverse ligament avulsion

34. Atlas Fractures - Treatment Collar Isolated anterior arch Isolated posterior arch Nondisplaced Jefferson fx

35. Atlas Fractures - Treatment Displaced <6.9 mm Halo vest * 3 mos Displaced >6.9 mm Halo traction (reduction) * several weeks followed by halo vest Immediate halo vest Posterior C1-2 fusion (unable to tolerate halo) After brace treatment complete confirm C1-2 stability Flexion/extension films C1-2 fusion for ADI > 5mm

36. Fusion options Gallie Post-op halo Brooks Jenkins Transarticular Screws C1 lateral mass/C2 pars-pedicle screws Atlas Fractures - Treatment

37. Odontoid Fractures Most common fracture of Axis (nearly 2/3 of all C2 Fxs) 10 – 20 % of all cervical fractures Etiology Bimodal distribution Young - high energy, multi-trauma Elderly - low energy, isolated injury (most common C-spine Fx elderly)

38. Odontoid Fractures Anderson and D’Alonzo Type I 2 % Type II 50-75 % Type III 15-25 %

39. Treatment Options odontoid fractures Type 1 C-Collar beware unrecognized AOD

40. Treatment Options odontoid fracture Type 3 C-Collar SOMI brace Halo Vest 10-15% nonunion rate

41. Treatment Options odontoid fracture Type 2 C-Collar SOMI brace Halo Vest Odontoid Screw C1-2 posterior fusion

42. Type II Fracture Nonunion Risk Factors Nonunion 10-70% Initial displacement > 6mm Age > 60 yr old Delay Diagnosis > 3 wk Angulation > 10° Posterior displacement Schatzker 1971 Anderson 1974 Apuzzo 1978 Ekong 1981 Hadley 1985 Clark 1985 Dunn 1986 Hanssen 1987 Schweigel 1987 Hadley 1989 Hanigan 1993 Ryan 1993 Seybold 1997

43. Anterior Odontoid Screw Fixation Indications Displaced Type II, Shallow Type III Polytrauma patient Unable to tolerate halo-vest Early displacement despite halo-vest Contraindications Non-reducible odontoid fracture Body habitus (Barrel chest ) Associated TAL injury Subacute injury (> 6 months) Reverse oblique

44. Posterior Odontoid Fixation Options –Posterior wiring Up to 25% pseudoarthrosis Halo vest necessary (?) Dickman JNS 1996, Grob Spine 1992 –Transarticular screw fixation Magerl and Steeman Cerv Spine 1987 Reilly et al, JSD 2003 –C1 lateral mass - C2 pars/pedicle screw

45. The course of the vertebral artery through C1 and C2 determines the possibility of placing screws for fixation of fractures and dislocations C1 lateral mass screws C1-2 transarticular screws C2 pedicle/pars screws

46. Harms J, Melcher RP. Posterior C1– C2 fusion with polyaxial screw and rod fixation. Spine 2001;26:2467– 71. C1 lateral mass screws

47. ..

48. pedicle Pars transarticular C2 pars/pedicle

49. Traumatic Spondylolisthesis Axis (Hangman’s Fracture) Second most common fracture of axis 25% of C2 injuries Most common mechanism of injury is MVA

50. Hangman’s Fracture Younger age group (Avg 38 yrs) Usually due to hyperextension-axial compression forces (windshield strike) Neurologic injury seen in only 5-10 % (acutely decompresses canal) Traditional treatment has been Halo-vest Collar adequate if < 6 mm displaced Coric et al JNS 1996

53. Hangman’s Fracture Treatment Type III Treatment Options Posterior –Open reduction and C1-C3 fusion –Direct pars repair and C2-C3 fusion Anterior –C2/C3 ACDF with instrumentation

54. Halo Immobilization

56. In-hospital mortality rates in Pts > 70 yr age Rx’d Halo-vest 20 – 36% Elderly and Halo-vest Treatment E-mail OTA about Questions/Comments If you would like to volunteer as an author for the Resident Slide Project or recommend updates to any of the following slides, please send an e-mail to ota@aaos.orgota@aaos.org Return to Spine Index