Spine and Spinal Trauma

1. Spine and Spinal Trauma Rebecca Burton-MacLeod R1, Emergency Medicine Aug 21, 2003

2. Numbers • ~10,000 new cases each year in US • over 1 million pts with blunt trauma and potential c-spine injury seen in US EDs • of these pts, <1% have acute # or spinal injury • SIGNIFICANT CONSEQUENCES!

3. Who? • Age >65 • male • white or “other” ethnicity

4. How? • MVA 50% • falls 20% • sporting accidents 15% • remainder from acts of human violence • predisposing factors--arthritic disease, OP, Ca

5. Anatomy….[oh no!] • 33 vertebrae--7cervical, 12thoracic, 5lumbar, 5sacral (fused), 4coccyx (fused) • intervertebral discs separate them, and ligaments support • spinal cord goes from midbrain to L2 level • anterior column (vertebral bodies, discs, ant/post longitudinal ligs) and posterior column (pedicles, transverse processes, facets, laminae, spinous processes, spinal canal, nuchal/capsular ligs, ligamentum flavum)

6. Spinal column

7. Million $ question... • Stable--disruption of only one of ant/post columns • vs • unstable--disruption of both columns at same level OR c1/2 #

8. Classification of spinal column injuries • Flexion • extension • flexion-rotation • vertical compression

9. Flexion injuries

10. Flexion injuries • Wedge # • teardrop #

11. Flexion injuries • Clay shoveller # (lat) • clay shoveller # (AP)

12. Flexion injuries • Bilateral facet dislocation

13. Extension injuries

14. Extension injuries • Extension teardrop #

15. Extension injuries • Hangmans #

16. Flexion-rotation injuries

17. Flexion-rotation injuries • Unilateral facet disloc

18. Vertical compression injuries

19. Vertical compression injuries • Burst #

20. Vertical compression injuries • Jefferson #

21. Spinal cord injuries • Primary--mechanical disruption of axons as result of stretch, laceration, or vascular injury • vs • secondary--progressive injury; caused by free radical formation, uncontrolled calcium influx, ischemia, lipid peroxidation

22. Secondary spinal cord injuries • Reversible/preventable factors: • hypogylcemia • hypoxia • hypotension • hyperthermia • mishandling by medical personnel

23. Spinal cord injuries • Complete--total loss of motor power and sensation distal to lesion • vs • incomplete--3 syndromes (central cord, anterior cord, Brown-Sequard), SCIWORA

24. Complete spinal cord injuries • If lasts >24hrs, 99% will have no functional recovery • must look for any evidence of cord function • sacral sparing is key! • Ddx: spinal shock • cannot diagnose complete injury until bulbocavernosus reflex is elicited

25. Incomplete spinal cord injuries

26. Incomplete spinal cord injuries • Central cord syndrome: • affect upper extremities>lower extremities • 50+% of patients with a severe central cord syndrome have a return of bowel and bladder control, become ambulatory, and regain some hand function • may mimic complete cord injury

27. Incomplete spinal cord injuries • Anterior cord syndrome • caused by: • cervical flexion injuries causing cord contusion • protrusion of a bony fragment or herniated intervertebral disk into the spinal canal • laceration or thrombosis of the anterior spinal artery • systemic embolization or prolonged cross-clamping of the aorta

28. Anterior cord s/o cont’d • paralysis below level of injury • hypalgesia below the level of injury • preservation of posterior column functions (position, touch, and vibratory sensations)

29. Incomplete spinal cord injuries • Brown-Sequard syndrome: • hemisection of spinal cord • often due to penetrating trauma, or may be due to # of lat mass of c-spine • ipsilateral paralysis and contralateral sensory hypesthesia below level of injury • most retain bladder/bowel control

30. SCIWORA • Usually <8yrs of age following c-spine injury; no injury seen on complete plain radiographic series • possibly due to immature anatomy and increased ligamentous elasticity • causes transient spinal column subluxation, stretching of the spinal cord, and variable degrees of vascular compromise

31. SCIWORA cont’d • brief episode of upper extremity weakness or paresthesias, followed by the development of neurologic deficits that appear hours to days later

32. on exam • Vitals, GCS • inspection--facial contusions, head injuries, trunk contusions, obvious deformities/penetrating injuries • palpation--spine for step-off deformity, widened interspinous space • neuro exam

33. Motor exam

34. Deep tendon reflexes • UMN--present reflexes (but may be absent acutely during spinal shock) • LMN--absent reflexes

35. Sensory function • Light touch--posterior column function • painful touch--anterior spinothalamic function

36. Investigations • Plain radiography • CT • MRI

37. Radiography • NEXUS: • 34,069 pts with blunt trauma • 818 pts with c-spine injuries • sensitivity 98.0-99.6%, specificity 12.9% • 23 pts (3 potentially unstable) had injuries not visualized on radiography (2.81% of all pts with radiography performed)

38. Radiography • NEXUS criteria for c-spine xrays: • all 5 criteria must be met, or else xray: • absence of midline tenderness • normal alertness • no evidence of intoxication** • no focal neurological deficit • no painful distracting injuries** • ** poorly reproducible

39. Radiography • Canadian C-spine rules: • 8924 pts enrolled with trauma to head/neck, stable vitals, GCS=15 • excluded pts--<16yrs, penetrating trauma, known vertebral disease • 151 clinically important c-spine injuries (1.7%) • sensitivity 100%, specificity 42.5% • identified 27 of 28 unimportant c-spine injuries (missed c3 avulsion #) • potential radiography rate 58.2% (down from 68.9%!!)

40. Radiography • Canadian c-spine rules for radiography: • high risk factors? (>=65yrs, dangerous mechanism, paresthesias) • **must have radiography • low risk factors? (simple rear-end MVC, sitting in ED, ambulatory since injury, delayed onset pain, absence midline c-spine tenderness) • **then may assess range of motion • rotate neck to left and right? (45degrees both directions) • **do not require radiography

41. Radiography • Standard trauma series (Caroline’s excellent review!!): • lateral • AP • open-mouth odontoid • oblique view--posterior laminar fracture, a unilateral facet dislocation, or a real subluxation • flexion-extension views--if severe pain but normal 3views

42. CT • Indications: • inadequate radiography (as high as 25% for visualization of c7-t1) • suspicious radiography findings • fracture/displacement demonstrated by standard radiography • high clinical suspicion of injury, despite normal radiography • pts undergoing CT of head/abdomen may be considered

43. Pros evaluate spinal canal evaulates paravertebral soft tissues limited movement required Cons limited views of vert body displacement poor visualization of horizontal # **overcome by spiral CT CT *May eventually replace radiography, but not current standard of care as initial investigation*

44. CT • # right lateral mass

45. MRI • Excellent for evaluation of neurological injury • useful for: ligamentous injury, bony compression, epidural and subdural hemorrhage, and vertebral artery occlusion

46. MRI • C-spinal cord hemorrhage

47. Management Goals • Preservation of pts life • optimizing potential for recovery of neurologic function

48. Management • Prehospital: • high index of suspicion • spinal immobilization--c-collar and backboard with sandbags and tape

49. ED Management • ABC’s: • above level of c3 often loss of resp drive • avoid hyperextension of neck if intubation necessary • above level of t6 often “functional sympathectomy”--systemic hypotension • treat with Trendelenburg position and crystalloid infusion

50. ED Management • Pharm: (NASCIS II and III): • 487 pts--overall analysis negative • 193 pts--positive effect post hoc analysis • modest improvement in functional recovery at 1yr • loading dose 30mg/kg IV within 8hrs of injury • if loading dose started within 3hrs, then 5.4mg/kg/h IV drip for 24hrs** • if loading dose started 3-8hrs post-injury, then 5.4mg/kg/h IV drip for 48hrs** • no benefit if given >8hrs after injury, or for penetrating injuries • **Class II evidence (guideline)