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568

CHAPTER 81

MAXILLOFACIAL TRAUMA

Ethan M. Ross, MD, and Carlo L. Rosen, MD

1. What are the facial bones?

The facial bones are the frontal, temporal, nasal, ethmoid, lacrimal, palatine, sphenoid,

zygoma, maxilla, and mandible.

2. What is the initial approach to a patient with maxillofacial trauma?

The initial management of patients with facial trauma should follow the ABCs (airway,

breathing, and circulation) of trauma resuscitation. The airway is the primary concern and can

be challenging in these patients. Signiﬁcant facial trauma may cause swelling or distortion of

the airway as a result of bleeding, loose teeth, or fractures. In patients with mandibular

fractures, the tongue loses its support and can occlude the airway. Early endotracheal

intubation should be considered in patients with signiﬁcant midface or mandibular trauma,

especially if they exhibit any signs of airway distress. Standard methods of intubation, such as

rapid-sequence intubation, should be attempted ﬁrst. However, airway distortion resulting

from facial trauma sometimes necessitates a cricothyrotomy. All patients with facial and head

trauma should be assumed to have a cervical spine injury. In-line cervical spine stabilization

should be used during intubation. The incidence of cervical spine injuries in patients with

facial trauma is 1% to 4%.

3. Which procedure is contraindicated in patients with maxillofacial trauma?

Nasogastric tube placement should not be performed because of the risk of intracranial

placement through a fracture in the cribriform plate. The small size and ﬂexibility of the

nasogastric tube allow it to be misdirected through a fracture into the brain. There is

also a theoretical concern about placing a nasotracheal tube through the cribriform plate

into the brain. However, an endotracheal tube is larger and more rigid than a nasogastric

tube. The literature suggests that the risk of intracranial placement of a nasotracheal

tube is low.

4. What is a blow-out fracture? What is the entrapment syndrome?

A blow-out fracture is a fracture of the orbital ﬂoor that results from a direct blow to

the orbit. Increased intraorbital pressure causes rupture of the ﬂoor of the orbit. The

entrapment syndrome is binocular diplopia and paralysis of upward gaze that results from

entrapment of the inferior rectus muscle in the orbital wall defect. Diplopia is noted by

having the patient follow and count ﬁngers on upward gaze. Other physical ﬁndings include

infraorbital anesthesia and enophthalmos (posterior displacement of the globe into the

orbit). Patients may have tenderness or step-offs at the infraorbital rim or subcutaneous

emphysema secondary to a fracture into the maxillary sinus. Ophthalmologic evaluation

for associated orbital trauma (globe rupture, hyphema, retinal tear or detachment,

blindness), despite an initially normal visual acuity and funduscopic examination,

should be considered.

Chapter 81 MAXILLOFACIAL TRAUMA 569

5. What are Le Fort fractures?

The Le Fort classiﬁcation is used to describe maxillary fractures (Fig. 81-1). Midface fractures

are diagnosed by grasping the upper alveolar ridge and noting which part of the midface moves.

Le Fort I, a transverse fracture just above the teeth at the level of the nasal fossa, allows

movement of the alveolar ridge and hard palate.

Le Fort II, a pyramidal fracture with its apex just above the bridge of the nose and

extending laterally and interiorly through the infraorbital rims, allows movement of the

maxilla, nose, and infraorbital rims.

Le Fort III, the most serious of the Le Fort fractures, represents complete craniofacial

disruption and involves fractures of the zygoma, infraorbital rims, and maxilla.

1. Eyelid edema

2. Enophthalmos

3. Proptosis

4. Limitation of upward gaze

5. Diplopia

6. Infraorbital anesthesia

7. Subcutaneous emphysema

KEY POINTS: CLINICAL SIGNS OF ORBITAL FRACTURES

Figure 81-1. Le Fort classiﬁcation of facial fractures. Le Fort I: palato

facial disjunction. Le Fort II: pyramidal disjunction. Le Fort III: craniofa-

cial disjunction. (From Cantrill SV: Face. In Marx JA, Hockberger RS,

Walls RM, et al, editors: Rosen’s emergency medicine: concepts and

clinical practice, ed 5, St. Louis, 2002, Mosby, p 325.)

Chapter 81 MAXILLOFACIAL TRAUMA570

It is rare for these fracture types to occur in isolation; they usually occur in combination (one

type on one side of the face and another on the other side).

6. Is there a role for screening patients with LeFort fractures for blunt

cerebrovascular injury?

Blunt cerebrovascular injury (BCVI) to the carotid or vertebral artery is becoming

increasingly recognized in blunt trauma and is found in nearly 1% of all blunt trauma

patients when screening protocols are used. Signiﬁcant morbidity and mortality is

encountered if left untreated and there is frequently a clinically silent period before

symptoms occur. Although no standard exists for screening, guidelines are being

developed that suggest screening should be undertaken with computed tomographic

angiography (CTA) or standard angiography in patients with signs or symptoms of BCVI

and patients at high risk. High-risk patients include those with a LeFort II or III fracture,

certain cervical spine fracture patterns (subluxation, fractures extending into the

transverse foramen, fractures of C1–C3), basilar skull fracture with carotid canal

involvement, diffuse axonal injury with Glasgow Coma Scale ,6, or near hanging with

anoxic brain injury.

7. When are nasal radiographs indicated?

Almost never. Nasal fractures typically are a clinical diagnosis without the need for routine

radiographs. Physical examination may reveal swelling, angulation, bony crepitus, deformity,

pain on palpation, epistaxis, and periorbital ecchymosis. Nasal radiographs are neither

sensitive nor speciﬁc for fractures. The results do not alter management.

8. What is a septal hematoma? Why is it important?

All patients with nasal trauma and suspicion of a nasal fracture require inspection of the nasal

septum for a septal hematoma. This is a collection of blood between the mucoperichondrium

and the cartilage of the septum. It appears as a grape-like swelling over the nasal septum. If

left undrained, it may result in septal abscess, necrosis of the nasal cartilage, and permanent

deformity. If a septal hematoma is identiﬁed, incision and drainage is indicated in the ED,

followed by nasal packing, antistaphylococcal antibiotics (prophylaxis for toxic shock

syndrome), and prompt referral.

9. When should a consultation be obtained for a nasal fracture?

Most nasal fractures do not require immediate reduction unless there is signiﬁcant deformity

and malalignment. After anesthetizing the nose with lidocaine or tetracaine-soaked gauze

or pledgets, early reduction of an angulated fracture is performed by exerting ﬁrm, quick

pressure toward the midline with both thumbs. Patients should be referred to a maxillofacial

or plastic surgeon for follow-up in 4 to 7 days. Immediate consultation is suggested for nasal

fractures with associated facial fractures, cerebrospinal ﬂuid rhinorrhea, and sustained

epistaxis.

10. How is a frontal sinus fracture diagnosed?

Frontal sinus fracture should be suspected in any patient with a severe blow to the forehead.

There is often an associated brain injury. The clinical signs include supraorbital nerve

anesthesia, anosmia, cerebrospinal ﬂuid rhinorrhea, subconjunctival hemorrhage, crepitus,

and tenderness to palpation. The preferred diagnostic modality is computed tomography (CT)

to determine if there is involvement of the anterior or posterior walls of the sinus or

intracranial hemorrhage.

11. How are frontal sinus fractures treated?

After surgical consultation, patients with nondisplaced anterior wall fractures may be

discharged on prophylactic antibiotics, with instructions to avoid Valsalva maneuvers and

to follow up in 1 week with the surgical consultant. Patients with displaced anterior wall

and sinus ﬂoor fractures require surgical consultation, admission, and antibiotic therapy.

Chapter 81 MAXILLOFACIAL TRAUMA 571

Patients with posterior wall fractures require antibiotics and immediate neurosurgical

consultation.

12. What are the classic zygoma fractures?

The zygoma is the third most commonly fractured facial bone (after the nose and mandible).

Zygoma fractures are classiﬁed into three basic types:

Arch: The bone may be fractured in one or two places and may be nondisplaced or

displaced medially. Pain and trismus are caused by bony arch fragments abutting the

coronoid process of the mandible. Because the masseter muscle originates on the zygoma,

any movement causes further arch disruption. The fracture is diagnosed by the plain

radiograph bucket-handle view (submentovertex).

Tripod: Also termed a zygomaticomaxillary fracture, this is the most serious type of

zygoma fracture and involves the infraorbital rim, the zygomaticofrontal suture, and the

zygomaticotemporal suture. Clinical signs include deformity (ﬂatness of the cheek),

infraorbital nerve hypesthesia, inferior rectus muscle entrapment, and diplopia on upward

gaze. Although these fractures may be detected on plain radiographs (Waters and Caldwell

views), CT is necessary to better deﬁne the extent of the fracture. For these fractures,

admission and consultation with a maxillofacial surgeon are required.

Body: Fracture of the body of the zygoma, which involves the clinical signs and symptoms

of the tripod fracture, results from severe force and leads to exaggerated malar depression.

13. What is the tongue blade test?

Patients with mandible fractures have mandibular tenderness and deformity, sublingual

hematoma, and malocclusion on physical examination. The jaw appears asymmetric, with

deviation toward the side of the fracture. The tongue blade test is performed by asking the

patient to bite down on a tongue depressor. The tongue blade should be twisted by the

examiner. If there is no fracture, the patient should be able to break the blade. In the presence

of a mandible fracture, the patient opens his or her mouth and the tongue blade remains intact.

14. Which imaging studies should be ordered to diagnose a mandible fracture?

Mandible fractures are the second most common facial fracture. Multiple fractures are

common (.50%) because of the ring structure of the bone. Always check for a second

fracture. If available, the Panorex view is the most useful view for detecting mandible

fractures. It provides a 180-degree view of the mandible and can detect fractures in all regions

of the mandible, including symphyseal fractures that can be missed with the other views. If a

Panorex radiograph is unavailable, the standard mandible series can be used. This comprises

a posteroanterior view (for detecting fractures of the angle and body of the mandible), lateral

and bilateral oblique views (for detection of rami fractures), Townes view (anteroposterior

view that projects the rami and condyles), and often a submentovertex view. A condylar

fracture may be missed by plain radiographs. If this fracture is suspected and the plain

radiographs are negative, facial CT is indicated.

15. What are the most commonly fractured areas of the mandible?

The most commonly fractured areas are the body, the condyle, and the angle of the mandible.

16. What is the mechanism for a temporomandibular joint dislocation? How is it

treated?

Temporomandibular joint dislocation can result from blunt trauma to the mandible, but it also

can occur with exaggerated opening or closing of the jaw such as after a seizure or with

yawning. Patients with a temporomandibular joint dislocation present with jaw deviation away

from the side of the dislocation if it is a unilateral dislocation or with the mandible pushed

forward (underbite) if it is a bilateral dislocation. After conscious sedation with benzodiazepine

for masseter muscle relaxation and a narcotic for pain relief, the emergency physician should

place gauze-wrapped thumbs on the posterior molars while standing above and behind the

patient. The mandible is then pushed downward and posterior.

Chapter 81 MAXILLOFACIAL TRAUMA572

17. When is a CT scan indicated in the evaluation of maxillofacial trauma?

In patients with a history of facial trauma but with minimal physical ﬁndings consistent with

fractures or an equivocal examination, plain radiography should be used as a screening test.

The standard plain ﬁlm series of the face includes a Waters (occipitomental) view, Caldwell

(occipitofrontal) view, submentovertex view, and lateral view. The Waters view visualizes

the orbital rim, infraorbital ﬂoor, maxilla, and maxillary sinuses and is useful as an initial

examination in patients with suspected orbital ﬂoor fractures. Performance of this view

requires that the cervical spine be clear because the patient is in the prone position. Fluid in

the maxillary sinus is indirect evidence of fracture. The Caldwell view allows visualization of

the superior orbital rim and the frontal sinuses. The lateral view shows the anterior wall of the

frontal sinus and the anterior and posterior walls of the maxillary sinus.

In patients with physical ﬁndings that are highly suggestive of facial fractures (tenderness,

step-offs, crepitus, or evidence of entrapment), some authors recommend proceeding directly

to CT. This allows appropriate surgical planning. High-resolution, thin-cut CT scanning is the

preferred modality for the elucidation of bony and soft-tissue injury in maxillofacial trauma.

This is the preferred test in any patient with suspected tripod, orbital, or midface fractures. In

patients with suspected orbital fractures, CT scan with coronal and axial sections should be

ordered (2- to 3-mm cuts).

18. How do I recognize an injury to Stenson’s duct?

Stenson’s (parotid) duct arises from the parotid gland and courses from the level of the

external auditory canal (superﬁcial) through the buccinator muscle to open at the level of the

upper second molar (Fig. 81-2). Any laceration at this level may involve the parotid gland,

parotid duct, or buccal branch of the facial nerve. Laceration of the parotid system is

Figure 81-2. Parotid gland and parotid duct with nearby branches of the facial nerve. Line

B demonstrates approximate course of parotid duct from parotid gland, entering mouth at

junction of lines A and B. (From Cantrill SV: Face. In Marx JA, Hockberger RS, Walls RM,

et al, editors: Rosen’s emergency medicine: concepts and clinical practice, ed 5 St. Louis,

2002, Mosby, p 323.)

Chapter 81 MAXILLOFACIAL TRAUMA 573

recognized by a ﬂow of saliva from the wound or bloody drainage from the duct oriﬁce.

Careful exploration reveals whether the ﬂow is from the parotid gland or duct. The buccal

branch of the facial nerve travels in close proximity to Stenson’s duct; injury leads to drooping

of the upper lip, which indicates a possible parotid duct injury. To assess for parotid duct

patency, the parotid gland should be milked to see if saliva is expressed from the intraoral

opening of the parotid duct. Damage to the duct requires repair over a stent and plastic

surgical consultation.

19. When should closure of a facial laceration be deferred?

Closure of facial lacerations in the ED depends on the severity of facial and systemic injuries.

Complex lacerations in patients needing operative intervention should be cleansed with normal

saline, covered with moist gauze, and deferred for intraoperative closure. Closure of the highly

vascular tissues of the face may be delayed for up to 24 hours. Wounds involving the facial

nerve, lacrimal duct, parotid duct, and avulsions should be referred on presentation to the

appropriate surgeon for deﬁnitive care.

20. What deformity may arise from blunt trauma to the ear?

An acute auricular hematoma is a collection of blood separating the perichondrium from the

underlying cartilaginous layer that may develop after a blow to the ear. If a hematoma is left

undrained or an auricular compression dressing not applied after incision and drainage of a

hematoma or repair of a pinna laceration secondary to blunt trauma to the ear, necrosis of the

cartilage may develop with resultant deformity known as Cauliﬂower ear.

21. How is the ear anesthetized?

A subcutaneous circumferential injection of plain lidocaine should be placed at the base of the

pinna. Lacerations in the external auditory require topical anesthesia with 4% lidocaine or

local injection.

BIBLIOGRAPHY

1. Cantrill SV: Face. In Marx JA, Hockberger RS, Walls RM, et al, editors: Rosen’s emergency medicine: concepts

and clinical practice, ed 5, St. Louis, 2002, Mosby, pp 314–329.

2. Cothren CC, Bifﬂ WL, Moore EE, et al: Treatment for blunt cerebrovascular injuries: equivalence of

anticoagulation and antiplatelet agents. Arch Surg 144(7):685–690, 2009.

3. Druelinger L, Guenther M, Marchand EG: Radiographic evaluation of the facial complex. Emerg Med Clin North

Am 18:393–410, 2000.

4. Ellis E, Scott K: Assessment of patients with facial fractures. Emerg Med Clin North Am 18:411–448, 2000.

5. Jones SE, Mahendran S: Interventions for an acute auricular haematoma. Cochrane Database Syst Rev

(2):CD004166, 2004.

6. MacLaughlin J, Colucciello S: Maxillofacial injuries. In Wolfson AB, Hendey GW, Hendry PL, et al, editors:

Harwood-Nuss’ Clinical practice of emergency medicine, ed 4, Philadelphia, 2005, Lippincott Williams &

Wilkins, pp 928–937.

7. Rosen CL, Wolfe RE, Chew S, et al: Blind nasotracheal intubation in the presence of facial trauma. J Emerg

Med 15:141–145, 1997.

574

CHAPTER 82

CERVICAL SPINE AND

SPINAL CORD TRAUMA

Michael J. Klevens, MD, FAAEM, and Robert M. McNamara, MD, FAAEM

1. What is the annual incidence of spinal cord injury (SCI)?

Approximately 12,000 new cases per year. Of these causes, the percentage of violent causes

has been increasing.

2. Name the most common causes of SCI.

Vehicular crashes (42.1%)

Falls (26.7%)

Violence, primarily gunshot wounds (15.1%)

Sports (7.6%)

Other (8.6%)

3. What are the most common levels of injury?

The most frequent level of injury is C5, followed by C4, C6, C7, T12, and L1. Overall about half

are cervical injuries.

4. In patients discharged from the hospital with neurologic impairment, what

percentage has paraplegia and what percentage has tetraplegia

(quadriplegia)?

Incomplete tetraplegia (30.1%)

Complete paraplegia (25.6%)

Complete tetraplegia (20.4%)

Incomplete paraplegia (18.5%)

One percent has complete recovery by discharge. An injury to one of the eight cervical

vertebrae can cause tetraplegia. People with paraplegia have injuries to the thoracic, lumbar,

or sacral regions. Over the past 15 years, the percentage of people with incomplete tetraplegia

has increased slightly, while complete paraplegia has decreased slightly.

5. If most spinal injuries do not cause neurologic injury, why do I care?

The management of any spinal injury is important because improper care can result in

permanent neurologic injury. It is important to have an index of suspicion for injury and

proper immobilization and handling of the patient. It is imperative to have good-quality

diagnostic imaging because inadequate studies and interpretation errors can lead to

permanent injury.

6. What is the ﬁnancial impact of an SCI?

Huge. The health care and living costs can vary greatly, depending on what severity of injury

was sustained and the age of the individual at time of injury. The estimated yearly costs can

range from $16,500 to $143,500. This does not include the ﬁrst year costs, which range from

$236,000 to $801,000. The lifetime costs can range from $704,000 to $3.1 million.

7. What is the average age of the person who sustains an SCI?

SCI is devastating in that it primarily affects young healthy adults. Since 2005, the average age

at injury is 40.2 years. The predominant age range is between 16 and 30. An overwhelming

percentage of injuries are suffered by males. There has been a slight trend toward older age

recently, likely reﬂecting the preserved mobility of an aging population.

Chapter 82 CERVICAL SPINE AND SPINAL CORD TRAUMA 575

8. Name the causes of reduced life expectancy in SCI patients.

Pneumonia, pulmonary emboli, and sepsis.

9. Are there any underlying conditions that could precipitate or heighten the

chance of an SCI?

Less force is required to cause fractures in the elderly. Rheumatoid arthritis can lead to

subluxation problems at C1 and C2. Normal development of the odontoid may not occur in a

Down syndrome patient. Osteoporosis and metastatic cancer may lead to a vertebral fracture

with insigniﬁcant trauma.

10. How do I immobilize the potential spinal injury patient?

When any spinal injury is suspected, initially, the entire spine should be immobilized with a

long board. The cervical spine is immobilized with a hard collar. There are several different

types of stiff cervical collars, such as the Philadelphia or Ambu brand collars. The emergency

medical service (EMS) stabilization may also include the forehead taped to the board and

accessory towel, sandbag, or other bolsters to prevent further neck movement. The sandbag

and tape method without a rigid collar support should not be used. It is interesting that total

spinal immobilization has never been proven to prevent secondary spinal injury. However,

there continue to be sporadic case reports of such injuries. Therefore, it is prudent to follow

these initial guidelines. It is recommended that the patient be removed from the long board as

soon as possible to prevent soft tissue injury.

11. How should one approach the patient with potential spinal injury?

There are several mnemonics for the initial stabilization of any trauma patient. Advanced

trauma life support (ATLS) teaches the ABCDE mnemonic:

A 5 Airway

B 5 Breathing

C 5 Circulation

D 5 Disability

E 5 Exposure

According to another mnemonic, a proper history is A MUST:

A 5 Altered mental state. Check for drugs or alcohol.

M 5 Mechanism.* Does the potential for injury exist?

U 5 Underlying conditions. Are high-risk factors for fractures present?

S 5 Symptoms. Is pain, paresthesia, or neurologic compromise part of the picture?

T 5 Timing. When did the symptoms begin in relation to the event?

*Because fall injuries are common, the physician should get information as to the height

of the fall and any preceding events such as syncope, chest pain, or seizure.

12. What should be assessed on physical examination?

There are two key areas: the spine itself and the neurologic examination. The spine is palpated

to assess for tenderness, deformity/step-off, and muscle spasm. It is important to understand

that the examiner feels only the posterior elements of the vertebrae; therefore, a fracture may

be present despite a lack of tenderness. The neurologic examination should include motor

function, sensory function, some aspect of posterior column function (position and vibration),

and a rectal examination. Regarding sensory testing, the assessment of light touch examines

the integrity of the posterior neurological column while pinprick testing assesses the anterior

column. In an unconscious patient, the only clues may be poor rectal tone, priapism, absence

of deep tendon reﬂexes, or diaphragmatic breathing.

13. What is neurogenic shock? How is it treated?

Neurogenic shock is a syndrome with loss of neurologic function and accompanying

autonomic tone. This is usually exhibited by ﬂaccid paralysis with loss of reﬂexes and loss

of urinary and rectal tone. Accompanying this are bradycardia, hypotension, hypothermia,

and ileus. The diagnosis of neurogenic shock should only be made after all other forms of

Chapter 82 CERVICAL SPINE AND SPINAL CORD TRAUMA576

shock have been eliminated. Hypotension is usually successfully treated with rapid infusion

of crystalloid. If intravenous ﬂuids are not adequate to maintain organ perfusion, the use

of dopamine or phenylephrine may be beneﬁcial. Bradycardia can be treated with atropine or

dopamine. In refractory bradycardia, a pacemaker may be required. In most cases of

neurogenic shock, hypotension resolves within 24 to 48 hours.

14. What are the general principles of emergency treatment in the patient with

spinal cord trauma?

First, do no harm. As stated previously, that means proper immobilization and coordinated

movement of the patient, when absolutely necessary. A higher level of cervical injury results in a

more devastating injury to the patient. Any patient with an injury above C5 probably should be

intubated because the phrenic nerve roots, which supply the diaphragm, emerge from C3 to C5.

Rapid-sequence intubation (RSI) oral-tracheal intubation with manual in-line cervical-spine

stabilization is considered the safest way to intubate these patients. Early gastric and bladder

decompression are also indicated. Overhydration should be avoided so as to not cause pulmonary

edema. The absence of pain below the level of injury can mask other injuries. The patient with

neurologic deﬁcit faces a difﬁcult hospital stay, and the ED should use full sterile precautions for

any procedure such as urinary catheters or central venous access when possible.

15. How do I determine which patients need spine radiographs?

There are two validated decision rules available to the emergency physician. One is the

National Emergency X-Radiography Utilization Study (NEXUS) decision rule. The other is the

Canadian C-Spine Rule (CCR). Both have been shown to reduce the number of radiographs

necessary to identify important cervical-spine injury.

16. What are the NEXUS criteria?

No midline cervical tenderness

No focal neurologic deﬁcit

Normal alertness

No intoxication

No painful distracting injury

If patients meet the criteria, there is a high likelihood that they have a low probability of injury

and that cervical radiography is not needed. In this large multicenter study, the overall rate of

missed cervical spine injuries was less than 1 in 4,000 patients. Note that there are speciﬁc

deﬁnitions of the previous ﬁve criteria that must be reviewed when applying the NEXUS

criteria. This rule was 99.6% sensitive and 12.9% speciﬁc for signiﬁcant injury.

17. What is the CCR?

The CCR asks three questions:

Is there any high-risk factor that mandates radiography? These are:

a. age . 65

b. signiﬁcant mechanism of injury (i.e., fall from .1 m, axial loading injury, high speed

MVA/rollover/ejection, bike collision)

c. the presence of paresthesias

Can the patient be assessed safely for range of motion (simple mechanism, sitting position

in the ED. ambulatory at any time, delayed onset of neck pain, or absence of midline

cervical spine tenderness)?

Can the patient actively rotate the neck 45 degrees to the left and the right?

This study had a sensitivity of 100% and a speciﬁcity of 42.5% for identifying clinically

important cervical-spine injuries. Again, one needs to review the rule completely before

applying it to patients.

18. What are distracting injuries?

NEXUS: includes a long list such as long bone fractures, large lacerations, visceral injury, and

burns

CCR: injuries such as fractures that are so severely painful that the neck examination is unreliable.

Chapter 82 CERVICAL SPINE AND SPINAL CORD TRAUMA 577

19. Can these decision rules be applied to children?

It is difﬁcult to validate the NEXUS or CCR in children because there has been a paucity of

studies in this population. Additionally, some of the criteria in the CCR and NEXUS are difﬁcult

to verify in toddlers and children because of their inherent immaturity and unpredictability.

20. Which type of radiographs should be

obtained?

The standard three-view of the cervical spine is

an anteroposterior (AP), lateral, and open-mouth

(odontoid). During the initial evaluation, a cross-

table lateral radiograph should be taken because

the patient does not have to move. It is extremely

important that cervical-spine precautions not be

discontinued based solely on the cross-table

lateral. Some studies have reported that up to

18% of cervical-spine injuries are missed with the

cross-table lateral radiograph alone. The most

commonly missed injuries are at C1 to C2,

followed by the lower C6-C7-T1 junction. In the

elderly, C1 and C2 fractures account for

approximately 70% of cervical-spine fractures.

21. How do I interpret the lateral cervical

spine radiograph?

The ﬁrst rule is to make sure that the radiograph is

technically adequate and that the top of T1 is visible

on the ﬁlm. Next, follow the mnemonic ABCS:

A 5 Alignment. Check for a smooth line at the

anterior and posterior aspect of the

vertebral bodies and the spinolaminar

line from C1 to T1 (Fig. 82-1)

B 5 Bones. Check each vertebral body to

ensure that the anterior and posterior heights

are similar (.3 mm difference suggests

fracture); follow the vertebrae out to the

laminae and spinous process. Look carefully

at the upper and lower cervical segments

where fractures are likely to be missed.

Examine the ring of C2, which can show a

fracture through the upper portion of the

vertebral body of C2.

C 5 Cartilage. Check the intervertebral joint

spaces and the facet joints.

S 5 Soft-tissue spaces. Look for prevertebral

swelling, especially at the C2 to C3 area

(. 5 mm) and check the predental space

(Fig. 82-2), which should be less than

3 mm in adults and less than 5 mm in

children. From C4 to C7 the soft-tissue

thickness should not be greater than 22 mm.

22. What are the indications for ﬂexion-

extension views of the cervical spine?

Based on the NEXUS study, ﬂexion-extension imaging

is unnecessary in the acute evaluation of patients

Figure 82-1. Curve of alignment.

Figure 82-2. Posterior cervical

line and predental space.