Cervical Spine and Spinal

Cord Injuries

Spinal Cord Injury : Epidemiology

ƒ 12 to 53 per million population per year in the U.S.A.

ƒ 12,000 new paraplegics & quadriplegics per year

ƒ 4000 deaths per year in the fieldƒ 1000 deaths per year in hospitalƒ Lifetime care costs now > $1,000,000

per case

Spinal Cord Injury (SCI) : Etiology

ƒ Motor vehicle crashes : 46 %

ƒ Falls : 26 %

ƒ Diving / Sports : 11 %

ƒ Gunshot wounds / stabbings : 10 %*

ƒ Miscellaneous : 7 %

* > 50% of SCI in some cities such as Detroit are due to gunshot wounds (GSW's)

Indications to Get Cervical Spine Films for Traumaƒ Appropriate mechanism of traumaƒ Neck painƒ Neck tenderness (palpate under cervical collar)ƒ Decreased pain perception–Head trauma (sufficient to affect mental status)–Alcohol or drugs–Children < 2 years old–Mentally retarded or dementia

ƒ Penetrating traumaƒ Neurologic symptoms or findingsƒ ? if another painful distracting injury

Cervical Spine Radiology Film Choices

ƒ 3 view : cross-table lateral + odontoid + AP

ƒ 5 view : 3 view + right & left obliquesƒ 3 or 5 view + flexion / extensionƒ Swimmer's view to see lower C-spineƒ Computed tomography (CT)ƒ Conventional tomographyƒ Magnetic Resonance Imaging (MRI)

Note : No advantage shown for 5 view over the 3 view series

MRI scan showing prevertebral edema (white arrows), cord injury (open arrow), and bone marrow edema

MRI scan showing spinal cord hemorrhage and rupture of the posterior longitudinal ligament

The Myth of the "Occult" Cervical Spine Fracture

ƒ Reviewed by Holliman & Wuerz : Amer. Journal Emer. Med., Nov. 1992 ; 10 (6) : 611-612.

ƒ All previous reported "occult" cases (with 2 poorly documented exceptions) had intracranial injury, intoxication, neck pain or tenderness, and / or neurologic signs

ƒ Two large prospective series (see next 2 slides) showed no fractures in patients not having one of the features listed on the previous slide under "indications for C-spine films"

ƒ This also was validated by the report of the NEXUS study in the year 2000

1992 Los Angeles Prospective Study on Cervical Spine Trauma Films

ƒ Hoffman et al., Ann Emer Med 1992 ; 21 : 1454-1460.

ƒ 974 cases from 1987 to 1989ƒ 27 C-spine fractures identified

–All had midline tenderness or decreased alertness, except :ƒOne with no pain or tenderness but blood alcohol > 200 mg %

ƒOne with distracting pelvic & femur fractures (? poor documentation of symptoms by the housestaff for this case)

1996 Los Angeles Prospective Study of Asymptomatic Trauma Patients

ƒ Velmahos et al., J Trauma 1996 ; 40 : 768-774.

ƒ 549 cases from July 1994 to June 1995ƒ Inclusion criteria :

–Collared, alert, cooperative, no alcohol on breath–No cervical pain or tenderness, or pain on motion (3 steps)

ƒ Results : "no acute cervical spine pathology" in any of these patients

ƒ Potential cost savings by not X-raying these patients : $ 242,000

The National Emergency X-Radiography Utilization Study (NEXUS)ƒ Started in 1998ƒ 21 participating medical centersƒ Reported in NEJM (Hoffman et al., 343 : 94-99)

in July 2000 on 34,069 enrolled patientsƒ 818 cases had cervical spine injuryƒ The 5 "low risk" criteria identified all but 2

clinically significant C-spine injuries (negative predictive value 99.8 %)

ƒ The "low risk" criteria if applied would have avoided radiographic imaging in 12.6 % of the patients

The Five "Low Risk" Criteria Identified by the NEXUS Study

ƒ No midline cervical tendernessƒ No focal neurologic deficitƒ Normal alertnessƒ No intoxicationƒ No painful other distracting

injury Most emergency physicians now think that if the patient does not have any of these 5, then cervical radiographs are not needed (note the additional considerations on the earlier slide)

Cervical Trauma : Indications for Computed Tomography

ƒ Lower cervical spine not seen well on lateral (must be able to see all 7 vertebrae and the top surface of T1 for lateral plain film to be regarded as adequate)

ƒ Vertebral body burst fracturesƒ Suspected posterior column fracturesƒ A suspected, but not clearly defined,

fracture on plain filmsƒ Marked osteoarthritis present

Cervical Trauma : Indications for Conventional Tomography

ƒ Suspected fracture at base of odontoid (if only conventional CT available ; spiral CT visualizes odontoid fractures well)

ƒ Computed tomography (CT) scan marred by streak artifact from metal

ƒ Suspected facet fracturesƒ Patient is too heavy (> 350 lbs.

or 160 kg.) for the CT scanner

Cervical Trauma : Indications for Flexion / Extension Views*ƒ Mild subluxation but no fracture seenƒ Prevertebral soft tissue swelling but no

fracture seenƒ Spinal cord injury with normal plain films & CT

scanƒ Persistent severe neck pain with normal

screening films.

* Note : These can also be considered indications for (if available) stat Magnetic Resonance Imaging (MRI) scan.

If done, the flexion & extension should always be directly supervised by a physician, and stopped at the point at which the patient develops any increased pain or neuro symptom.

Cervical Spine Injury : Clinical Assessment

ƒ ABC's first (include "hard" immobilization)ƒ Maintain immobilization, but open the

collar & palpate neck & observe anterior neck

ƒ Clinical assessment features:–Pain / tenderness–Deformity / step-off–Edema / ecchymosis–Muscle spasm–Head position / abnormal tilt–Tracheal deviation / hematoma

This patient proved to have locked facets at C5/6

Spine Injury : Neurologic Assessment

ƒ Motor strengthƒ Sensory disturbancesƒ Reflex changesƒ Autonomic dysfunctionƒ Rectal sphincter tone

Clinical Findings : Cervical Cord Injury

ƒ Flaccid arreflexiaƒ Diaphragmatic breathingƒ Pain response above clavicle

onlyƒ Motor response limited to

forearm flexionƒ Priapismƒ Neurogenic shock

Specific Spinal Cord Injury Syndromes

ƒ Brown-Sequard Syndrome :–Lateral hemisection of the cord–Ipsilateral motor paralysis & contralateral loss of pain & temperature sensation

ƒ Central Cord Syndrome :–Motor & sensory dysfunction worse in the upper than the lower extremities

ƒ Anterior Cord Syndrome :–Motor paralysis & loss of pain & temperature sensation ; vibration & position sense preserved

ƒ Posterior Cord Syndrome : loss of position & vibration sense only

Neurogenic Shock from Spinal Cord Injury

ƒ Due to loss of sympathetic outflowƒ Basically is peripheral vasodilatation &

venous blood poolingƒ Hypotension usually also with

bradycardiaƒ Rx with IV fluids +/- alpha agonists

(norepi or dopamine drip, ephedrine) +/- atropine

ƒ IV methylprednisolone 30 mg/kg (indicated if < 8 hours from time of injury)

Cervical Spine Injury : "Spinal Shock"

ƒ Is an "electrical" or depolarization injury

ƒ NOT a circulatory phenomenonƒ May represent electrical "stunning"

of cord functionƒ Occurs immediately after time of

injuryƒ Features:

–Flaccidity–Loss of reflexes

ƒ Can have full recovery in some patients

Treatment of Cervical Fractures and Suspected Spinal Cord Injury

ƒ Maintain immobilization in hard collarƒ Avoid traction / distractionƒ Film rest of spine (T-spine & L-spine) if

any sensory deficit presentƒ Support circulation with IV fluids +/-

alpha vasopressors if neurogenic shockƒ Antibiotics if open fractureƒ Neurosurg. / ortho. consult (consider

transfer)ƒ High dose steroids if SCI

Soft cervical collar (left) and Philadelphia collar (right)

“Stiff-Neck” brand of cervical immobilization collar

Effectiveness of High Dose Steroid Rx of Spinal Cord Injuries

ƒ The Second National Acute Spinal Cord Injury Study (NASCIS II)

ƒ Results reported in New Eng. J. Med. 1990 ; 322 : 1405-1411

ƒ Prospective, randomized, double-blind, placebo control multicenter study

ƒ Compared high dose methylprednisolone vs. naloxone vs. placebo

ƒ Found that naloxone was not effective

Conclusions of NASCIS II Study

ƒ Methylprednisolone (Solu-Medrol) at a dose of 30 mg/kg bolus followed by IV drip at 5.4 mg/kg/hr for 23 hours :–Significantly enhances recovery (both motor & sensory) from complete & incomplete acute spinal cord injuries, IF started within 8 hours of injury

However, many emergency physicians now think that the benefits of the steroids are very limited (improvement of only one or 2 spinal levels in the paraplegic patient) and there are increased complications (infections, peptic ulcers / GI bleeding) from the steroids

Results of the Third National Acute Spinal Cord Injury Trial (NASCIS 3)

ƒ Better motor recovery if methylprednisolone (MP) 5.4 mg/kg/hr IV drip continued for 48 hours in patients first treated with bolus MP 3 to 8 hours post-injury

ƒ Recovery rates were the same for using MP drip for just 24 hours (if Rx started < 3 hours from injury) as for using tirilazad (a potent lipid peroxidation inhibitor) 2.5 mg/kg bolus IV q 6 hours for 48 hours

ƒ Complications were less in the tirilazad group

Indications for Emergent Surgery for Cervical Spine Injuries

ƒ Acute anterior cord syndromeƒ Ascending level of neuro deficitƒ Compound (open) fracture

–GSW's–Other penetrating trauma–Associated posterior pharyngeal trauma

ƒ Pedicle fracture with nerve root symptomsƒ Vertebral artery injuryƒ Note that any wound that penetrates the platysma

should be evaluated by a surgeon , & usually surgically explored (may need preop esophagoscopy or gastrografin swallow and / or angiography to R/O esophageal or vascular injury)

C-Spine Trauma : What to Look for on Lateral Films

ƒ All 7 vertebrae and top of TIƒ 3 lines :–Anterior edge of vertebral bodies–Posterior edge of vertebral bodies –Anterior edge of spinous processes

ƒ Prevertebral space–C2 to C4 : < 5 mm ; below C4 : < 22 mm

ƒ Predental space–Adults : < 3mm ; Children : < 5 mm

ƒ Bony structures, facet jointsƒ Soft tissuesƒ Skull and mandible

These two lines define the spinal canal

What to Look for on the A-P Radiograph

ƒ Interspinous distance > 1.5 times the adjacent interspinous distance : anterior dislocation

ƒ Double appearing spinous process : Clay Shoveler's fracture

ƒ Deviation or rotation of spinous process : unilateral facet locking

ƒ Note : all these injuries have obvious signs on lateral view

AP view of patient with C2 fracture and C7 fracture-dislocation ; note rotation of spinous processes

C-Spine Trauma : Injury Mechanism Classification

ƒ Flexion –Anterior subluxation–Bilateral interfacetal dislocation–Wedge fracture vertebral body–Flexion teardrop fracture–Clay Shoveler's fracture

ƒ Extension–Central Cord Syndrome ; may have normal X-ray–Extension teardrop fracture–Hangman's fracture–Posterior atlantal arch fracture

C-Spine Trauma : Injury Mechanism Classification (cont.)

ƒ Rotation–Unilateral facet dislocation–Unilateral pillar fracture

ƒ Vertical compression–Jefferson fracture of atlas–Burst fracture of vertebral body

ƒ Odontoid fracture–Type I : (Fx of tip) : mythical (not ever seen clinically)–Type II : across base of odontoid–Type III : extends into C2 body at an angle

C-Spine Injuries : Degree of Stability

A. Stable 1. Anterior subluxation 2. Unilateral facet dislocation 3. Simple wedge fracture 4. Burst fracture of lower cervical vertebrae 5. Posterior neural arch fracture of atlas 6. Pillar fracture 7. Clay-Shoveler's fractureB. Unstable 1. Bilateral facet dislocation 2. Flexion teardrop fracture 3. Extension teardrop fracture (stable in flexion, unstable in extension) 4. Hangman's fracture 5. Jefferson fracture of atlas 6. Hyperextension fracture - dislocation

Definite Signs of Unstable C-spine Injury

ƒ All anterior or posterior elements fractured

ƒ > 3.5 mm horizontal vertebral body displacement

ƒ > 11 degrees of kyphotic angulation

Incidence of Spinal Cord Injuries Occurring with Vertebral Injuries

Type of Injury % with Neurologic DeficitFracture of vertebral body only 3Fracture of posterior elements only 19Fracture of posterior elements and vertebral body 11Dislocation only 17Dislocation with fracture of posterior elements 27Dislocation with fracture of vertebral body 56Dislocation with fracture of posterior elements and vertebral body 61

Levels of Injury(Data from Hershey C-spine Study)

Site of Fx / Dislocation

C1C2 bodyC2 dens

C3C4 C5C6C7

Number of Fractures

611446

191217

Total 79

Number with SCI

13025

1475

What is the correct interpretation of this film ?

The answer to the previous question is “inadequate film” ; note that in this adequate view of the same patient, now we can see a significant fracture of C7

What injury does this film show in this patient struck on the forehead by a heavy metal beam and brought to the emergency department in cardiac arrest ?

What fracture is the black arrow pointing to ?

C-Spine TraumaThe Jefferson Fracture

ƒ Is a burst fracture (Fx) of the atlas–Fracture through anterior and posterior arches of C1–Transverse atlantal ligament disrupted–Unstable–Best diagnosed on open-mouth (odontoid) viewƒLook for spreading of the lateral masses of C1 (the corners of the lateral masses of C1 do not line up with the corners of C2 if a Fx is present)

Lateral spread of the lateral masses of C1 with a Jefferson fracture

Conventional tomograms showing fracture of the right lateral mass and spreading of both lateral masses of C1 with a Jefferson fracture

Fracture of C1 which was only visible on this open mouth view

What injury does this film show ?

Coned-down view of same patient showing widened predental space (rupture of transverse atlantoaxial ligaments)

The “ring sign” of C2 ; normal C2 (on left) should show a nice round “ring” appearance ; note disruption of the “ring” in the film on the right ; this patient had a C2 body fracture

Disruption of the “ring” sign of C2 from an odontoid fracture ; note also the widened prevertebral space (probably from hematoma from the fracture)

What injury does this “open mouth” or odontoid view show ?

Type 2 odontoid fracture seen only on the open mouth view of this patient

What 2 fractures are seen here ?

What injury is shown on this film ?

What is the name of this fracture ?

C-Spine TraumaThe "Hangman's Fracture"

ƒ Is a traumatic spondylolysis of C2–Bilateral pedicle fracture of C2–Usually no SCI (if from striking head vertically on inside of car roof in motor vehicle crash)–Prevertebral swelling may compromise airway–Best diagnosed on lateral viewƒNormal C2 body should have a "ring" appearance, so a C2 Fx often results in disruption of the "ring line" seen on the lateral film

What injury is shown in this 16 year old male injured in a motor vehicle crash ?

What 2 level injury is shown on this radiograph ?

C-Spine TraumaAnterior Subluxation

ƒ The posterior ligament complex is disrupted–Anterior ligament complex intact–> 3 mm vertebral body displacement is abnormal, and if present, this injury should be suspected–May be unstable ( increased displacement with flexion)–Often will need further evaluation with either MRI or careful flexion-extension views

What 2 level injury is shown on this radiograph ?

C-Spine TraumaWedge Fracture of the Vertebral Body

ƒ Ligaments are usually intact–Is usually mechanically stable–+ Soft tissue swelling–Loss of vertebral body height anteriorly–No vertical fracture line–May require further evaluation with computed tomography

Vertebral body burst fractures

C-Spine TraumaVertebral Body Burst Fracture

ƒ Usually mechanically stable–Posterior ligaments intact–Has both vertical and horizontal fracture lines–Often have SCI (bone fragments in canal)–Usually requires further evaluation with computed tomography to see if there is any bone fragment impinging on the spinal canal

CT scan of C7 burst fracture with bone fragments in the spinal canal (the patient had a spinal cord injury)

What injury is shown, and what is its mechanism ?

C-Spine TraumaFlexion Teardrop Fracture

ƒ Is a fracture of the lower anterior corner of the vertebral body (results in separated triangular fragment)

ƒ Unstableƒ Often have anterior cord

syndromeƒ All ligaments disrupted

(Anterior longitudinal ligament is buckled)

What injury is shown, and what is its mechanism ?

C-Spine TraumaExtension Teardrop Fracture

ƒ Fracture of the upper anterior corner of vertebral body (results in separated triangular fragment)

ƒ Stable in flexion ƒ Unstable in extension

Wedge compression of the vertebral body with an extension teardrop fracture

What 2 injuries are shown here ?

C-Spine TraumaUnilateral Facet Dislocation

ƒ Superior facet rests in intervertebral foramen

ƒ Mechanically stableƒ Anterior displacement < 1/2 vertebral body

widthƒ Above the level of injury the interfacetal

joints are not superimposed (they appear normal below the injury)

ƒ AP view shows spinous process rotation

Unilateral facet dislocation

Widening of C5 disc space and unilateral locked facet

CT scan of unilateral locked facet (right side) at C4

What injury is shown here ?

C-Spine TraumaBilateral Interfacetal Dislocation

ƒ Unstableƒ High incidence of cord injuryƒ Dislocated facets pass up and

over the inferior facets–Complete = vertebral body displaced > 1/2 width of vertebral body–Incomplete = dislocation < 1/2 vertebral body width

Bilateral facet dislocation

Bilateral locked facets at C6-7 and bilateral laminar fractures of C6

CT scan of same patient showing bilateral facet locking and bilateral laminar fractures (i = inferior facet, s = superior facet)

What injury is shown ?

C-Spine TraumaClay-Soveler's Fracture

ƒ Is an avulsion fracture of spinous process–Most common at C7, C6, T1–Stable–No treatment usually needed (except pain meds & maybe soft C-collar for comfort)–May be marker for another injury !

Early Complications of Spinal Cord Injury

ƒ Hypoventilation leading to pneumonia

ƒ Vomiting with aspiration due to head immobilization

ƒ Pressure soresƒ Urinary tract infectionƒ Autonomic dysreflexia

–Can be due to urine retention and bladder distention

Adjunctive Agents Not Yet Proven to Help Spinal Cord Injuries

ƒ Naloxoneƒ Mannitol / diureticsƒ Hypothermiaƒ Antioxidantsƒ Calcium channel blockersƒ Barbiturates

Hanging and Strangulation Injuries

ƒ 3500 deaths per year in U.S.ƒ Third most common form of

suicideƒ Ligature or manual

strangulation causes this pathologic sequence:–Venous obstruction : stagnant hypoxia : loss of consciousness : flaccidity : arterial occlusion : airway collapse : death

ƒ Judicial hanging by contrast causes high spinal cord transection

Hanging and Strangulation Injuries

ƒ Potential injuries to rule out :–Airway compromise from hematoma–Cervical spine fracture–Carotid thrombosis / intimal flap–Laryngeal fracture–Cerebral edema / increased ICP–Concurrent medication or drug overdose–Vocal cord paralysis

Treatment of Hanging or Strangulation Injuries

ƒ Airway management / oxygenƒ C-spine immobilization until films checkedƒ Hyperventilationƒ Solu-Medrol IV if any possible cord injuryƒ +/- mannitol / diuretics / barbiturates for

ICPƒ Intensive Care Unit admissionƒ Observe at least 24 hrs for airway

problemsƒ Check vocal cord function when extubatedƒ Psychiatry consult when stable

Cervical Trauma : Summary

ƒ Assess for possible cervical trauma & immobilize neck as part of primary survey

ƒ Decide if radiographic studies needed as part of secondary survey

ƒ Start IV steroids early if possible spinal cord injury

ƒ Decide if subspecialist management or transfer of patient needed