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 (r adiological ABC) for analyzing plain films [164]: A1: appropriateness: correct indication and right patient A2: adequacy: extent (occiput to T1, penetration, rotation/projection) A3: 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 32117 acute trauma patients. Cervical spine injuries were missed in 34 symptomatic patients: 23 patients either did not have radio- graphs or had inadequate radiographs 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 cervical-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- 838 Section Fractures sion views to a three film series increases sensitivity (99%) and specificity (93%) withahighpositive(89%)andnegative(99%)predictivevalue,withfalsenega- 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 14577 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 2605 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 14755 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] suggested 12 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 atlantodentalinterval>4mminadultsor>5mminchildren narrowed or widened disc space wide apophyseal joints According to Clark et al. [50] For the upper cerv ical 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 >1mm translation of basion to dens top (normal 4 –5 mm) on flexion/extension (Fig. 5a) >7mm bilateral overhang C1 – C2 (see Fig. 5b) >45° axial rotation (C1 – C2) to one side >4mm C1–C2 translation measurement (see Fig. 5a) <13mm posterior body C2 – posterior ring C1 (see Fig. 5a) avulsion fracture of transverse ligament According to White and Panjabi [206], modified Cervical Spine Injuries Chapter 30 839 abc Figure 5. Instability of the upper cervical spine According to White and Panjabi [206]. a Assessment 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). b Assessment of the stability of the atlas on an open-mouth (ap) view of the dens. c Assessment 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]. ab Figure 6. Instability of the lower cervical spine a Sagittal 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]. b Angulation 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 840 Section Fractures 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 fracture 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 alsoshowsifthedensseparatesfromtheanteriorarchofC1withincreasedrota- 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 1199 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 radiographyidentified 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 forsequelaeoftheinjury 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. Cervical Spine Injuries Chapter 30 841 Neurophysiology 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 function (hand function, 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] 842 Section Fractures 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 (see Fig. 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 neckpain requires different investigations and management. Cervical Spine Injuries Chapter 30 843 For patients presenting to the emergency room after a blunt trauma, a distinct algorithm [93] is suggested ( Fig. 7)anddiagnostic 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- tionafterplainradiography,thisgroupshouldreceiveaCTscan. 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- 844 Section Fractures 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 IorIIneckpain(noradiculopathyorstructuralpathology)afteramotorvehicle 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 bending 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 immobilization of the occipital-C1 junc- Cervical Spine Injuries Chapter 30 845 abcd ef Figure 8. Orthosis and casts a, b Soft collar, c, d Philadelphia collar, e, f Minerva 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 Sc ot ch 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)orextension(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. 846 Section Fractures abc de Figure 9. Traction Gardner-Wells tongs. a Anteroposterior view; b view of spring-loaded stylet (unloaded); c view of spring-loaded stylet (loaded); d, e correct 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 Thehalovestisthefirst 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 distraction forces. The optimal position 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 Cervical Spine Injuries Chapter 30 847 . 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. 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. clinical examination and MEP recordings allows differentia- tion between the recovery of motor function (hand function, ambulatory capac- ity) and that of impulse transmission of descending motor