Spinal Disorders: Fundamentals of Diagnosis and Treatment Part 85 potx

Standard RadiographsRadiographs remain the imaging modality of first choice Radiography has been the standard initial “screening” examination used to eval-uate alert and stable patients

Standard Radiographs

Radiographs remain

the imaging modality

of first choice

Radiography has been the standard initial “screening” examination used to

eval-uate alert and stable patients with suspected cervical spine trauma At least three

views are recommended for alert and stable trauma patients [105]:

) anteroposterior view ) cross-table lateral view ) open-mouth dens view The lateral view should

extend from the occiput

to T1

The series of conventional radiographs has shown to be accurate in detecting cer-vical spine injuries in 84 % of cases [187] The lateral view should extend from the occiput to T1 The lower cervical spine is often obscured by the shadow of the shoulders elevated by muscle spasm or in patients with a “short neck.” It may be necessary to gently pull down the arms to visualize the entire T1 vertebra

In trauma patients for whom the standard three view series fails to

demon-strate the cervicothoracic junction, swimmer’s views (one arm abducted 180°, the other arm extended posteriorly) and supine oblique views were compared.

The authors concluded that both views show the alignment of the vertebral bod-ies with equal frequency However, supine oblique films are safer, expose patients

to less radiation, and are more often successful in demonstrating the posterior elements (e.g., riding facet) [110]

Oakley introduced a simple system (radiological ABC) for analyzing plain

films [164]:

) A 1: appropriateness: correct indication and right patient

) A 2: adequacy: extent (occiput to T1, penetration, rotation/projection)

) A 3: alignment: anterior aspect of vertebral bodies, posterior aspect of

verte-bral bodies, posterior pillar line, spinolaminar line; craniocervical and other lines and relationships

) B: bones

) C: connective tissues: pre-vertebral soft tissue, pre-dental space,

interverte-bral disc spaces, interspinous gaps Davis et al [61] described 32 117 acute trauma patients Cervical spine injuries were missed in 34 symptomatic patients: 23 patients either did not have radio-graphs or had inadequate radioradio-graphs that did not include the region of injury,

8 patients had adequate X-ray studies that were misread by the treating physi-cian, 1 patient had a missed injury that was undetectable on technically adequate films, even after retrospective review, and in the remaining 2 patients, the error was not described These results confirm that it is not uncommon to miss cervical spine injuries even with adequate plain radiographic assessment of the occiput through T1

The most common causes of missed cervical spine injury are:

) not obtaining radiographs ) making judgments on technically suboptimal films

Do not miss injuries

at the cervicocranial

and cervicothoracic junctions

The latter cause most commonly occurs at the occipital and cervical-thoracic junction levels [61, 87, 163]

Functional Views

Active flexion/extension is a safe and helpful test in conscious, cooperative patients to screen for ligamentous instability [164] Cervical instability occurred

in 8 % of alert, trauma patients in a Missouri Level I Trauma Center study, nearly half of whom had a normal three film series [130] The addition of

flexion/exten-sion views to a three film series increases sensitivity (99 %) and specificity (93 %)

with a high positive (89 %) and negative (99 %) predictive value, with false

nega-tives largely due to muscle spasm [130] However, flexion/extension radiography

is often unable to exclude instability until the spasm has resolved

Passive flexion/extension views in unconscious

or sedated patients must not be done

Passive flexion/extension views or fluoroscopy in unconscious or sedated

patients are technically inadequate in up to a third of cases and may even cause

devastating neurological deficits Their value therefore remains controversial

[164] Fortunately, the incidence of isolated ligamentous injury is low In a

retro-spective review of 14 577 blunt trauma victims in a tertiary referral center in

Bal-timore [48], 614 (4.2 %) of patients had cervical spine injuries, of whom only 87

(0.6 %) had isolated ligamentous injuries There were 2 605 patients in the series

with a GCS of less than 15 and only 14 (0.5 %) had isolated ligamentous injuries

Interestingly, 13 were identified on the initial lateral radiograph and the other

was diagnosed on CT In these cases of isolated ligamentous injury,

flexion/exten-sion views were not needed to reveal instability In a series of 14 755 trauma cases

in Los Angeles, 292 patients had cervical spinal injuries [64] Of these, 250

(85.6 %) had fractures, 10 % had subluxations (presumably with ligamentous

dis-ruption) and 3.8 % (11 patients) had isolated cord injury without fracture or

obvious ligamentous damage

Criteria for Trauma and Instability

Clark et al [50] suggested12 helpful signs in diagnosing cervical spine trauma

(Table 4):

Table 4 Radiographic signs of cervical spine trauma

Soft tissues

) retropharyngeal space > 7 mm in adults or children

) retrotracheal space > 14 mm in adults or > 22 mm in children

) displaced prevertebral fat stripe

) tracheal and laryngeal deviation

Vertebral alignment

) loss of lordosis

) acute kyphotic angulation

) torticollis

) widened intraspinous space

) axial rotation of vertebra

Abnormal joints

) atlantodental interval > 4 mm in adults or > 5 mm in children

) narrowed or widened disc space

) wide apophyseal joints

According to Clark et al [50]

For the upper cervical spine, White and Panjabi [206] suggested criteria

indica-tive of instability based on conventional radiography (Table 5,Fig 5a, b)

Table 5 Criteria for C0-C1-C2 instability

> 8° ) axial rotation C0 – C1 to one side

> 1 mm ) translation of basion to dens top (normal 4 – 5 mm) on flexion/extension (Fig 5a)

> 7 mm ) bilateral overhang C1 – C2 (seeFig 5b)

> 45° ) axial rotation (C1 – C2) to one side

> 4 mm ) C1 – C2 translation measurement (seeFig 5a)

< 13 mm ) posterior body C2 – posterior ring C1 (seeFig 5a)

) avulsion fracture of transverse ligament

According to White and Panjabi [206], modified

a b c

Figure 5 Instability of the upper cervical spine

According to White and Panjabi [206].aAssessment of C0 – 1-2 stabilities on lateral radiographs An increase of more than 1 mm in the distance between the basion (clivus) and the top of the dens on flexion/extension view (normal

4 – 5 mm) is indicative of an atlanto-occipital instability (only if transverse ligament is intact).bAssessment of the stability

of the atlas on an open-mouth (ap) view of the dens.cAssessment of the C0 – 1 stability A ratio of BC to AO of greater than 1 is indicative of an atlanto-occipital dislocation This is only valid in the absence of atlas fracture [206].

Figure 6 Instability of the lower cervical spine

aSagittal plane displacement or translation greater than 3.5 mm on either static or functional views should be consid-ered potentially unstable according to White and Panjabi [206].bAngulation between two vertebrae which is greater than 11° than that at either adjacent interspaces is interpreted as evidence of instability by White and Panjabi [206].

Kricun [120] suggested a criterion (Fig 5c) to detect atlanto-occipital dislocation

For the lower cervical spine, White and Panjabi [206] have suggested criteria

indicative of instability based on conventional radiographs (Fig 6a, b)

Computed Tomography

CT is the first choice

for unconscious

or polytraumatized patients

While standard radiographs remain the imaging study of first choice in alert and stable patients after cervical spine injuries, most large trauma centers now per-form multislice CT scans for the assessment of polytraumatized or unconscious

patients [164] The reasons why CT has surpassed radiography include the ease

of performance, speed of study, and, most importantly, the greater ability of CT

to detect fractures other than radiography [60] The craniocervical scans should

be of a maximum 2 mm thickness, because dens fractures can even be invisible

on 1-mm slices with reconstructions [164]

Computed tomography scans are sensitive for detecting characteristic

frac-ture patterns not seen on plain films One such pattern is the midsagittal fracfrac-ture

through the posterior vertebral wall and lamina These injuries are very

fre-quently associated with neurological deficits CT is the modality of choice for

diagnosing rotatory instability at the atlantoaxial joints [67, 68] Failure of C1 to

reposition on a left-and-right rotation CT scan indicates a fixed deformity CT

also shows if the dens separates from the anterior arch of C1 with increased

rota-tion Griffen et al [92] evaluated the role of standard radiographs and CT of the

cervical spine in the exclusion of cervical spine injury for adult blunt trauma

patients For 1 199 of patients at risk for cervical spine injury, both X-rays and CT

were performed to evaluate and compare cervical spine injuries In 116 patients,

a cervical spine injury (fracture or subluxation) was detected The injury was

CT can replace radiography identified on both plain films and CT scans in 75 patients but on CT only in 41

patients Importantly, all the injuries that were missed by plain films required

treatment

Magnetic Resonance Imaging

Magnetic resonance imaging is the imaging study of choice to exclude

discoliga-mentous injuries, if lateral cervical radiographs and CT are negative [164] MRI

is the modality of choice for evaluation of patients with neurological signs or

symptoms to assess soft tissue injury of the cord, disc and ligaments

MRI is additional to CT for specific diagnostic assessments

According to Richards [164], MRI exhibits several significant advantages in

the assessment of cervical trauma and allows the following to be diagnosed:

) discoligamentous lesions

) vertebral artery injuries

) neural encroachment and spinal cord contusion

) traumatic meningoceles or CSF leaks

) non-contiguous vertebral fractures

) injury sequelae (e.g., myelomalacia, cysts, syrinx)

Particularly, STIR sequences [164] are very helpful in visualizing posterior soft

tissue injuries and thereby helping to diagnose unstable Type B or Type C

frac-tures On the other hand, MRI of asymptomatic individuals has shown that

Morphological abnormali-ties are frequent at the craniocervical junctions and are not per se evidence for sequelae of the injury

asymmetry of alar ligaments, alterations of craniocervical and atlantoaxial

joints, and joint effusions are common in asymptomatic individuals The clinical

relevance of these MR findings is therefore limited in the identification of the

source of neck pain in traumatized patients [154] Furthermore, there is wide

variation of segmental motion in the upper cervical spine Differences in

right-to-left rotation are frequently encountered in an asymptomatic population

These measurements are unsuitable for indirect diagnosis of soft tissue lesions

after whiplash injury and should not be used as a basis for treatment guidelines

[153]

MRI is unsuitable for unstable polytrauma patients, because of the difficulties

in monitoring ventilated patients, in spite of the expensive specialized

equip-ment In addition, the MRI scanner is often remote from the emergency

depart-ment, and necessitates further hazardous transfers and delays

Neurophysiologic studies

are of prognostic value

for recovery after SCI

It has been shown that clinical and electrophysiological examinations (see Chap-ter 12) are of prognostic value for functional recovery in both ischemic and traumatic SCI [111] Motor evoked potential (MEP) recordings are of additional value to the clinical examination in uncooperative or incomprehensive patients The combination of clinical examination and MEP recordings allows differentia-tion between the recovery of motor funcdifferentia-tion (hand funcdifferentia-tion, ambulatory capac-ity) and that of impulse transmission of descending motor tracts [58] Further-more, the initial clinical and electrophysiological examinations are of value in assessment of the degree to which the patient will recover somatic nervous con-trol of bladder function [59]

Vascular Assessment

The association of cerebrovascular insufficiency and cervical fracture was first described by Suechting and French in a patient with Wallenberg’s syndrome occurring 4 days after a C5/C6 fracture dislocation injury [189] The incidence of The incidence of vertebral

artery insufficiency ranges

up to 45 % in patients

with cervical fractures

vertebral artery insufficiency (VAI) is reported in up to 46 % of patients with cer-vical fractures Fractures through the foramen transversarium (44 % [208]), facet fracture-dislocations (45 % [208]), or vertebral subluxation (80 % [208, 211]) have the highest incidence of post-traumatic VAI Most patients with VAI are asymptomatic Among the diagnostic modalities for identifying VAI, angiogra-phy, MRI, and duplex sonography seem to be of similar value, although none of these modalities has been compared in a clinical context of cervical injuries Biffl

et al [29] reported that patients not treated initially with intravenous heparin anticoagulation despite an asymptomatic VAI reported strokes more frequently However, because the risk of significant complications related to anticoagulation

is approximately 14 % in these studies, there is insufficient evidence to recom-mend anticoagulation in asymptomatic patients

Synopsis of Assessment Recommendations

The Neck Pain Task Force issued recommendations for the clinical management

of patients with neck pain presenting to the emergency room after motor vehicle collisions, falls and other mishaps involving blunt trauma to the neck [93] The task force proposed that the initial clinical assessment should classify patients into four broad categories or grades rather than establishing a specific structural diagnosis [93] (Table 6).

In Grade I neck pain, complaints of neck pain may be associated with stiffness

or tenderness but no significant neurological complaints There are no symp-toms or signs to seriously suggest major structural pathology, such as vertebral

Table 6 Grading of blunt neck injuries Grade I ) neck pain with no signs of serious pathology and no or little interference

with daily activities

Grade II ) neck pain with no signs of serious pathology, but interference with daily

activities

Grade III ) neck pain with neurological signs of nerve compression

Grade IV ) neck pain with signs of major structural pathology According to the Neck Pain Task Force [93]

Figure 7 Assessment recommendations

The assessment and management of blunt neck trauma in the emergency room as proposed by the Neck Pain Task

Force [93], reproduced with permission from Lippincott, Williams & Wilkins) High and low risk factors are defined

according to the Canadian C-Spine Rule (seeFig 4) [186].

fracture, dislocation, and injury to the spinal cord or nerves In Grade II neck

pain, complaints of neck pain are associated with interference in daily activities,

but no signs or symptoms to seriously suggest major structural pathology or

sig-nificant nerve root compression Interference with daily activities can be

ascer-tained by self-report questionnaires In Grade III neck pain, complaints of neck

pain are associated with significant neurological signs such as decreased deep

tendon reflexes, weakness, and/or sensory deficits These clinical signs suggest

malfunction of spinal nerves or the spinal cord The mere presence of pain or

numbness in the upper limb without definitive neurological findings and

consis-tent imaging studies does not warrant a Grade III neck pain designation Grade IV

includes complaints of neck pain and/or its associated disorders where the

exam-ining clinician detects signs or symptoms suggestive of major structural

pathol-ogy Each “grade” of neck pain requires different investigations and management

For patients presenting to the emergency room after a blunt trauma, a distinct

algorithm [93] is suggested ( Fig 7 ) and diagnostic work-up is recommended by

the Neck Pain Task Force [93]:

) Patients with suspected blunt trauma to the neck presenting to the emer-gency room with decreased level of consciousness, intoxication, and/or major distracting injuries should be considered high risk for cervical spine fracture or dislocation [105] A CT scan of the cervical spine should be con-sidered if available

) Alert (Glasgow Coma Scale of 15) and stable patients should be screened according to the NEXUS criteria or the Canadian C-Spine Rule [105, 186] ) Patients screened as low risk with the above criteria (i.e., Grade I and Grade II) do not require radiological investigation and should receive reassurance and supportive care

) Patients who do not meet the low-risk criteria (NEXUS, C-Spine Rule) [105, 186] should receive a plain (three-views) radiograph or a CT of the cervical spine (C0–T1) If suspicion remains about cervical spine fracture or disloca-tion after plain radiography, this group should receive a CT scan

) In the absence of radicular pain or neurological signs, and where radio-graphs and/or a CT scan rule out spinal fracture or dislocation, patients should be classified as Grade I or Grade II (as appropriate)

) Patients with radiographs or CT scan compatible with spinal fracture or dislocation and those with radicular findings (decreased deep tendon reflexes, weakness and/or sensory deficits) should be referred to a spinal surgery specialist for evaluation

) Flexion/extension radiographs, five-view radiographs, and MRI of the cervical spine do not add meaningful clinical information to the emergency management of blunt trauma to the neck in the absence of fracture, disloca-tion, or radicular signs [148]

General Treatment Principles

The general objectives of the treatment of cervical injuries are (Table 7):

Table 7 General objectives of treatment

) restoration of spinal alignment ) preservation or improvement of neurological function ) restoration of spinal stability ) avoidance of collateral damage

) restoration of spinal function ) resolution of pain

The treatment should provide a biological and biomechanical sound environ-ment that allows uneventful bone and soft-tissue healing and finally results in a stable, fully functional and pain-free spinal column These goals should be accomplished with a minimal risk of morbidity

Whiplash-Associated Disorders

Treatment recommendation cannot be solidly based on scientific evidence from the literature because of the poor methodological quality and inhomoge-neity of the studies [199] However, it appears that rest and immobilization using collars are not recommended for the treatment of whiplash, while active interventions, such as advice to “maintain normal activities,” might be effective

in acute whiplash patients [177, 198] In chronic WAD, a combination of

cogni-In WAD, reassurance about the absence of a structural lesion and the recommen-dation to maintain normal activities are most important for recovery

tive behavioral therapy with physical therapy intervention and coordination

exercise therapy appear to be effective [177] Recent research has demonstrated

that both coping behaviors and depressive symptomatology play a significant

role in the recovery of patients with WAD and need to be addressed at an early

stage [41, 42]

The Bone and Joint Decade Task Force recommends certain management

strategies which can help, at least in the short term In the early stages of Grade

I or II neck pain (no radiculopathy or structural pathology) after a motor vehicle

collision, the Neck Pain Task Force recommends the following clinical approach

[93]:

) reassurance about the absence of serious pathology

) education that the development of spinal instability, neurological injury or

serious ongoing disability is very unlikely

) promotion of timely return to normal activities of living

) if needed, exercise training and/or mobilization to provide short-term relief

Cervical sprains and strains of the cervical spine after non-motor vehicle

accidents are quite common [201] and similar treatment recommendations

apply

Non-operative Treatment Modalities

Cervical orthoses limit movement of the cervical spine by buttressing structures

at both ends of the neck, such as the chin and the thorax However, applied

pres-sure over time can lead to complications such as:

) pressure sores and skin ulcers

) weakening and atrophy of neck muscles

) contractures of soft tissues

) decrease in pulmonary function

) chronic pain syndrome

Collars

Soft collars ( Fig 8a, b) have a limited effect on controlling neck motion,

restrict-ing flexion/extension about 20 – 25 %, lateral bendrestrict-ing 8 %, and one-directional

rotation 17 % [155] A soft collar is at best useful for the acute (short-term)

treat-ment of minor cervical muscle strains and sprains However, soft collars are no

better than the recommendation of “return to normal activities” particularly not

in WADs [148] The Philadelphia collar ( Fig 8c, d) has been shown to control

neck motion, especially in the flexion/extension plane, much better than the soft

collar Restriction in flexion/extension is 71 %, lateral bending 34 %, and axial

rotation 56 % Disadvantages of the Philadelphia collar are the lack of control for

flexion/extension control in the upper cervical region and lateral bending and

axial rotation [155] Further, the Philadelphia collar was shown to elicit increased

occipital pressure, which may result in scalp ulcers, particularly in comatose

patients

Minerva Brace/Cast

A Minerva cervical brace is a cervicothoracal orthosis with mandibular,

occipi-tal, and forehead contact points Radiological evaluation showed the Minerva

cervical brace to limit flexion/extension in 79 %, lateral bending in 51 %, and

axial rotation in 88 % of cases [178] This brace provides adequate

immobiliza-tion between C1 and C7, with less rigid immobilizaimmobiliza-tion of the occipital-C1

junc-a b c d

Figure 8 Orthosis and casts

a,bSoft collar,c,dPhiladelphia collar,e,fMinerva cast.

tion The addition of the forehead strap and occipital flare assists in

immobiliz-ing C1–C2 [178] However, we prefer a customized Minerva cast made of a Scotch

cast, which can be individually molded and provides a reliable fixation which the patient cannot simply take off (Fig 8e, f)

Traction

The Gardner-Wells tongs (Fig 9a) can be applied using local anesthesia The pin application sites should be a finger breadth above the pinna of the auricle

of the ear in line with, or slightly posterior to, the external auditory canal (Fig 9d, e) The exact anteroposterior position can be chosen to help apply traction

with the neck in some flexion (posterior site) or extension (anterior site) The

device should be tightened until 1 mm of the spring-loaded stylet protrudes (Fig 9b, c), which corresponds to an average of 13.5 kg of compressive force

Of note, the pin only penetrates the external skull lamina The average force necessary to penetrate the inner table with cadaveric specimens with the tong pin was 73 kg [126], indicating a large safety margin If the device is planned

to remain for an extended time period, the marker should be tightened once again 24 – 48 h after application A nut located over each pin should be tight-ened down to the tong to secure the pins in position, minimizing the risk of break-out

Rule out AOD or

discoliga-mentous disruption before

applying traction

Although most cervical injuries can be stabilized with traction, it is manda-tory to rule out an atlanto-occipital dislocation or complete discoligamentous injuries before applying traction because of the inherent risk of rapid neurologi-cal deterioration, which can be irreversible

a b c

Figure 9 Traction

Gardner-Wells tongs.aAnteroposterior view;bview of spring-loaded stylet (unloaded);cview of spring-loaded stylet

(loaded);d,ecorrect positioning of the skull pins.

The initial weight should not exceed 5 – 7 kg (depending on body weight) and

increases incrementally (30 – 60 min) only after control imaging

Recommenda-tions for the maximum weight cannot be based on the literature However,

weights up to 60 kg have been reported [53], but we do not recommend to go to

that limit

Halo

The halo vest is the first conservative choice for unstable lesions

Since its introduction by Nickel [145, 146], the halo skeletal fixator has proved to

be the most rigid and effective method of cervical spine immobilization [116] It

was originally developed to immobilize the unstable cervical spine for surgical

arthrodesis in patients with poliomyelitis Longitudinal traction with a cranial

halo affords control and positioning in cervical flexion, extension, tilt, and

rota-tion as well as longitudinal distracrota-tion forces The optimal posirota-tion for anterior

halo pin placement is 1 cm superior to the orbital rim (eyebrow), above the lateral

two-thirds of the orbit, and below the greatest circumference of the skull This

area can be considered as a relatively “safe zone” ( Fig 10a, b) Ring or crown size

is determined by selection of a ring that provides 1 – 2 cm clearance around every