Neurologic Deterioration Secondary to Unrecognized Spinal Instability Following Trauma–A Multicenter Study

Home , Degloving, Major trauma, Spinal cord injury, Spinal fracture

Allan D. Levi, MD, PhD,* R. John Hurlbert, MD, PhD,† Paul Anderson, MD,‡ Michael Fehlings, MD, PhD,§ Raj Rampersaud, MD,§ Eric M. Massicotte, MD,§ John C. France, MD, Jean Charles Le Huec, MD, PhD,¶ Rune Hedlund, MD,** and Paul Arnold, MD††

Study Design. A retrospective study was undertaken their neurologic injury. The most common reason for the that evaluated the medical records and imaging studies of missed injury was insufficient imaging studies (58.3%), a subset of patients with spinal injury from large level I while only 33.3% were a result of misread radiographs or trauma centers. 8.3% poor quality radiographs. The incidence of missed Objective. To characterize patients with spinal injuries injuries resulting in neurologic injury in patients with who had neurologic deterioration due to unrecognized spine fractures or strains was 0.21%, and the incidence as instability. a percentage of all trauma patients evaluated was 0.025%. Summary of Background Data. Controversy exists re- Conclusions. This multicenter study establishes that garding the most appropriate imaging studies required to missed spinal injuries resulting in a neurologic deficit “clear” the spine in patients suspected of having a spinal continue to occur in major trauma centers despite the column injury. Although most bony and/or ligamentous presence of experienced personnel and sophisticated im- spine injuries are detected early, an occasional patient aging techniques. Older age, high impact accidents, and has an occult injury, which is not detected, and a poten- patients with insufficient imaging are at highest risk. tially straightforward problem becomes a neurologic ca- Key words: spinal instability, trauma, spinal clearance, tastrophe. spinal cord injury, radiculopathy. Spine 2006;31:451–458 Methods. The study was designed as a retrospective review of patients who had neurologic deterioration as a direct result of an unrecognized fracture, subluxation, or soft tissue injury of the cervical, thoracic, or lumbar spine from 8 One of the major goals of caring for the trauma patient is level I trauma centers. Demographics, injury information, the early detection and treatment of acute spinal injuries, and neurologic outcome were collected. The etiology and thereby preventing delayed neurologic deterioration incidence of the missed injury were determined. from a missed spinal injury. Although extensive re- Results. A total of 24 patients were identified who were treated or referred to 1 of the participating trauma sources are used to screen patients, the success of trauma centers and had an adverse neurologic outcome as a result teams at attaining this goal is unclear. Several studies of the missed injury. The average age of the patientswas 50 have reviewed the issue of missed injuries in the trauma years (range 18–92), and average delay in diagnosis was population, and the reported incidence of significant 19.8 days. Radiculopathy developed in 5 patients, 16 had spinal cord injuries, and 3 patients died as a result of missed spinal injuries is low, with an exact figure depen- dent on the study population.1–5 However, most of these studies are authored by general trauma surgeons and/or radiologists, with many of the recent reports lacking sufficient follow-up. From the *Department of Neurosurgery and the Miami Project to Cure Paralysis, University of Miami, Miami, FL; †Division of Neurosurgery, Spine surgeons in academic centers who specialize in Department of Clinical Neurosciences, University of Calgary, Calgary, trauma have a unique perspective on the issue of clearing Canada; ‡Department of Orthopedic and Neurological Surgery & Re- habilitation, University of Wisconsin–Madison, Madison, WI; §Divi- the spine because they are often the last treating physi- sions of Orthopaedic and Neurosurgery, Toronto Western Hospital, cian in cases in which instability or neurologic deficits Krembil Neuroscience Center, University of Toronto, Toronto, Ontario, from spinal injuries go undetected. There are certain spi- Canada; Department of Orthopedics, Robert C. Byrd Health Sciences Center, West Virginia University, WV; ¶Department of Ortho- nal fractures that if left undetected, will have only rela- Trauma, Hopital Tripode Pellegrin; **Department of Orthopedic Sur- tively minor consequences to the patient. Although this gery, Karolinska Institute, Huddinge University Hospital; and ††De- may be recorded as a missed injury in some studies, par- partment of Neurosurgery, University of Kansas, Kansas City, KS. Acknowledgment date: December 7, 2004. First revision date: January ticularly studies that use spinal computerized tomogra- 11, 2005. Second revision date: February 22, 2005. Acceptance date: phy (CT) as an end point, the significance of such minor February 23, 2005. fractures is probably limited.6–9 Of major interest is the The manuscript submitted does not contain information about medical device(s)/drug(s). detection and treatment of an injury that if missed, may No funds were received in support of this work. No benefits in any result in neurologic compromise. Because caring for a form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript. patient who has an adverse event from a missed spinal Address correspondence and reprint requests to Allan D. Levi, MD, injury is unlikely to be forgotten by the attending spine PhD, The Miami Project to Cure Paralysis, University of Miami School surgeon, a retrospective review, even many years after of Medicine, Department of Neurological Surgery, 2nd Floor, D4-6, 1095 NW 14th Terrace, Miami, FL 33136; E-mail: alevi@med. the event, will still likely accurately reflect the trauma miami.edu center’s experience.

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An evaluation of a specific patient population with gathered from 8 centers, including 4 from the United missed spinal injuries that subsequently has neurologic States, 2 from Canada, and 2 from Europe. The retro- deterioration may enable identification of risk factors spective review extended over a period of 2–8 years, associated with such injuries and assist in the improve- depending on the center submitting data. The number of ment of existing spinal protocols. Because these cases are submitted cases ranged from as many as 7 patients to as relatively uncommon events, the number of patients re- few as 1. The incidence of missed fractures resulting in a quired for the study is large. The purpose of this multi- neurologic deficit was calculated using 2 different de- center review was to determine the incidence and clinical nominators. First, the incidence of missed spinal injures factors associated with missing a spinal injury that leads presenting with a neurologic deficit relative to the total to neurologic deterioration. number of diagnosed spine injuries at all participating Materials and Methods centers was 0.21%, or approximately 1 in 500 cases. Second, using the total trauma population (44,520) seen The study was designed as a retrospective review of patients at all institutions as the denominator, the incidence was who presented to the emergency department or trauma service 0.025%, or approximately 1 in 4000 cases. and who had neurologic deterioration as a direct result of an Mean patient age was 50 years (range 18–92). The unrecognized fracture, subluxation, or soft tissue injury of the time to delayed diagnosis ranged from as short as 0 days cervical, thoracic, or lumbar spine from 8 level I trauma cen- to as long as 2 years after injury. There were 2 cases that ters. Spinal surgeons, members of the Spine Trauma Study Group, were surveyed as to whether they had experience in presented 1 and 2 years after injury, and were clearly treating patient(s) who had received “spinal clearance” after a outliers when compared to the other 22 patients. When trauma evaluation and subsequently had significant neurologic these 2 cases were excluded, the average time to delay in deterioration from an unrecognized spinal injury. The Spine diagnosis was 19.8 days. Trauma Study Group is an international group of approxi- The most common etiology of spinal trauma in our mately 50 neurosurgical and orthopedic spine surgeons from cohort was a motor vehicle accident (MVA) occurring in 13 different countries who are dedicated to advancing spine 17 patients, with the remainder stemming from falls (6) trauma care through multicenter analysis and research related and 1 industrial-related accident (Figure 1). Many of the to spine trauma and spinal cord injury. MVAs were high velocity injuries. The majority of spinal Surgeons who had met the aforementioned criteria obtained injuries were cervical cases (21/24), including injuries to institutional review board approval to evaluate further the the occipito-cervical junction (Table 1). The thoracic in- medical records and determine the nature and outcome of the unrecognized instability. To estimate the incidence of missed juries were mainly at the thoracolumbar junction. Mul- spinal injuries, each center was requested to provide data on tiple, nonspinal injuries were present in 8 of 24 patients. patients who were evaluated for trauma over that same period. Many of these concomitant injuries were serious associ- Specific data requested included the number of spine fractures, ated long bone fractures or intra-abdominal injuries. strains or sprains in the cervical, thoracic, and lumbar spine, Closed head injuries, which are believed to be a signifi- and the total number of patients evaluated for trauma in a cant confounding variable when clearing the spine, were given year. Patients with missed injuries referred from other seen in 8/24 patients. institutions were included in the overall assessment of the data, The neurologic deficits sustained as a result of the but not in the calculations of incidence. missed injury were radiculopathies in 5 and spinal cord The data collected included age, sex, mechanism of injury, injuries in 19 patients, including 3 who died of their level of injury, delay of diagnosis (days), neurologic sequelae of severe spinal cord injury. In each case, the patient under- the missed spinal injury, follow-up neurologic assessment, associated injuries at presentation, hospital course, and etiology went further imaging studies that defined the cause of the for the missed injury. Neurologic assessment of the missed in- new neurologic finding. Within the spinal cord injury jury was broadly categorized as either a radiculopathy or spinal group, 3 patients had complete loss of sensory and motor cord injury. The clinical degree of the spinal cord injury was function below their level of injury (ASIA A), while the categorized according to the American Spinal Injury Associa- remainder had variable and incomplete loss of function tion (ASIA) scale.10 Death was considered an end point when the missed injury and subsequent neurologic adverse event was the primary contributor to the death. Exclusion criteria included patients with missed spinal injuries or fractures but without neurologic deterioration. Patients who had deterioration from causes other than a missed injury were also excluded, such as application of traction, inappropriate positioning on a stretcher (e.g., ankylosing spondylitis), surgery, failed fusion, persistent compression, etc. Patients with recognized spinal instability, who were treated “suboptimally,” and then had neurologic deterioration were also excluded. Results Figure 1. Pie chart showing the most common mechanisms of A total of 24 patients had an adverse neurologic outcome injury within the group of patients (n ϭ 24) who had delayed as a result of the missed spinal injury. The data were neurologic deterioration. Neurologic Deterioration Secondary to Unrecognized Spinal Instability • Levi et al 453

Table 1. Summary of Day of Delayed Diagnosis, Level and Type of Injury, Mechanism of Injury, Associated Injuries, Including Closed Head Injury, Neurologic Sequelae of Missed Injury, and Reason Injury was Missed

Day of Delayed Missed Mechanism of Associated Injuries/Closed Neurologic Sequelae Reason Injury was Diagnosis Spinal Injury Injury Head Injury of Missed Injury Missed

6 L1/L2 Fracture MVA None SCI, Conus, ASIA D X-rays misread 30 Occipitoanterior MVA CHI, GCS Ϫ3 Death X-rays misread dislocation Facial degloving//CHI, GCS 11 7 C6/C7 Subluxation MVA SCI, ASIA D Insufficient imaging 1 C1/C2 Dislocation Pedestrian–MVA Splenic Lac, L Tib/Fib fracture/ Death X-rays misread CHI, GCS 7 0 C4 Burst fracture with Fall CHI, GCS 14 SCI, ASIA A Insufficient imaging partial subluxation of C4 on C5 21 T10 Chance* Fall None SCI, ASIA D X-rays misread 17 T12/L1 Fracture Fall None SCI, ASIA A X-rays misread dislocation 7 C6–C7 Subluxation MVA None SCI, ASIA C Insufficient imaging 42 C6/C7 Facet fracture MVA None SCI, ASIA D Poor quality images dislocation 730 C1C2 Dislocation MVA None SCI, ASIA D Insufficient imaging 365 C4C5 Bilateral facet Industrial None SCI, ASIA D Insufficient imaging subluxation accident 30 C4C5 Bilateral facet MVA None Radiculopathy- Insufficient imaging subluxation bilateral 14 C6–C7 Bilateral facet MVA None Radiculopathy Insufficient imaging subluxation 20 C6 Unilateral facet MVA None Radiculopathy Insufficient imaging fracture 1 C5 Fracture MVA Wrist fracture SCI, ASIA A Insufficient imaging 2 C6/7 Fracture MVA Bilateral tib-fib, hemothorax SCI, ASIA C X-rays misread dislocation 84 C4 Fracture with MVA Upper extremity* SCI, ASIA C X-rays misread C3/C4 subluxation 4 C5/6 Subluxation Fall None SCI, ASIA D Insufficient imaging 70 Type II odontoid* Fall None SCI, ASIA D Insufficient imaging 2 Occipitoanterior MVA Splenic laceration and multiple SCI, ASIA D Insufficient imaging dislocation ortho injuries/CHI, GCS 13 17 C4 Tear drop fracture, MVA CHI, GCS 13 SCI, ASIA D Insufficient imaging unilateral C5/6 facet luxation 42 T1 Burst*, with C7T1 MVA T6 Stable compression* Radiculopathy Poor quality images facet dislocation 17 C6C7 Perched facet - MVA None Radiculopathy Insufficient imaging superior C7 facet fracture 1 C5C6 Bilateral facet Fall Pubic Rami*/thoracic Death X-rays misread dislocation compression*

GCS indicates Glasgow Coma Scale; SCI, Spinal Cord Injury. * ϭ fracture

(3 patients with ASIA C and 10 with ASIA D). None of graphic investigations, the spinal injury would likely not the patients with ASIA A recovered, while most of those have been missed. There are 2 typical examples of such a with incomplete injuries and radiculopathies had vari- scenario presented in case Nos. 1 and 2. The next most able degrees of improvement. There were 3 patients who common reason was that imaging studies were com- died as a result of their missed injury, and all of these pleted but misinterpreted; another example for such a patients had either high complete spinal cord injuries or case is presented in case No. 3. Finally, 2 injuries resulted were elderly and had complications directly attributable from poor quality imaging studies. to their spinal cord injury. We further analyzed the group of patients with insuf- Finally, we determined “what was the major reason ficient imaging studies (n ϭ 14) to determine if the clin- for the missed injury,” according to the treating surgeon. ical and radiographic evaluation performed was in accor- The options included: (1) insufficient imaging studies dance with the EAST Practice Management Guidelines for completed, (2) sufficient imaging studies completed but Identifying Cervical Spine Instability after Trauma4,5 or misinterpreted, and (3) poor quality imaging studies. The the Neurosurgery Guidelines for the Management of most common etiology (14 of 24 cases) for the missed Acute Cervical Spine and Spinal Cord Injuries,11 which injury was insufficient imaging studies completed (Figure included both recommendation standards and options. 2). The definition of “insufficient” in these cases is that The 2 guidelines in their entirety cover numerous aspects had another imaging been added to the patient’s radio- of clearing the spine, including clinical and radiologic 454 Spine • Volume 31 • Number 4 • 2006

Figure 2. Bar graph of the most common reason for a missed fracture resulting in a delayed neurologic injury. assessments. In the subcategory with missed injuries as a Case No. 3. A 47-year-old male presented to the trauma result of insufficient imaging studies, 4 patients had no center after a high-speed MVA and was evaluated for imaging studies performed, 8 would not have likely been complaints of back pain. He was discharged after tho- missed if fine-cut CT was performed, and 2 would likely racic and lumbar spine plain radiographs were reported not have been missed had magnetic resonance imaging to be normal. He returned 6 days later with a left foot- (MRI) or dynamic imaging been performed. drop and urinary retention. Imaging studies on his second admission revealed a T12L1 fracture dislocation Case Studies (Figure 5A) and compression of the conus medullaris on Case No. 1. A 46-year-old female presented to the trauma MRI. He underwent a T12 laminectomy, reduction of center after a high-speed MVA, and was evaluated and the fracture dislocation, and a posterior fusion from T10 treated for multiple injuries, including abdominal and to L2 with pedicle screw instrumentation (Figure 5B). long bone fractures. She underwent a lateral c-spine ra- His symptoms resolved at 3-month follow-up. diograph, and was cleared despite overlying shadows Case No. 4. A 92-year-old male presented to the emer- present on the films (Figure 3A) and the absence of an gency department after a fall. The patient had an associ- anteroposterior view. Thirty-six hours later, she had ated thoracic compression fracture as well as a pubic quadriparesis (ASIA D) and bilateral CN XII paresis. CT ramus fracture. The patient received spinal clearance and with sagittal reconstructions showed an atlanto-occipital was mobilized. Soon after, he had a C5 complete quad- dislocation (Figure 3B). She underwent stabilization in a riplegia. Supine imaging studies on admission revealed a halo-vest, followed by an occiput to C2 fusion. Her subtle listhesis at C5C6 with otherwise relatively good quadriparesis improved, but she had persistent com- alignment on supine films and were reported to show plaints of dysphagia, dysarthria, and numbness. only degenerative changes (Figure 6A). On mobilization, Case No. 2. A 43-year-old female presented to the trauma after “spinal clearance,” imaging studies just after injury center after a high-speed MVA, and was evaluated and revealed a high-grade listhesis with bilateral jumped fac- treated for multiple injuries, including a facial degloving ets at C5C6. The patient ultimately died of complica- injury and a closed head injury (Glasgow coma scale ϭ tions related to his spinal cord injury. 11). She underwent lateral and anteroposterior cervical Discussion spine radiographs and thin-cut CT, both of which were reported as normal and was cleared. Seven days later, she The issue of missed spinal fractures after trauma has was noted to have progressive weakness of her hands and been the subject of several reports. Based on the finding was unable to walk, even with assistance (ASIA D). of these reports and recommendations of knowledgeable Emergency MRI was performed and showed bilateral bodies, such as Advanced Trauma Life Support, pro- perched facets at C6C7, with signal change involving the posed minimum standards to clear the spine1–5,9,11 have interspinous ligament of C6C7 and associated cord com- been developed, although there is no universal agreement pression (Figure 4). She underwent emergent anterior on the precise protocol to be performed in an individual cervical discectomy and fusion at C6C7 with fibular al- trauma victim or center.12,13 The reported incidence of lograft and plate. She improved after surgery but contin- missed spinal fracture after trauma varies between ued to complain of persistent numbness in her hand at 0.001% and 4.6%.1–3 Several reports have emphasized last follow-up. the importance of CT in identifying fractures, which may Neurologic Deterioration Secondary to Unrecognized Spinal Instability • Levi et al 455

Figure 4. MRI of the cervical spine. T2-weighted image illustrates a C6C7 bilateral facet dislocation, with high-signal intensity (arrow) within the interspinous ligament and relative anterolisthesis of C6 on C7. There is compression of the spinal cord from the posterior aspect of the C7 vertebral body. The posterior longitudinal ligament is avulsed from the back of the C6 vertebral body (*).

larly linear nondisplaced fractures of the vertebral body, lamina, and/or transverse process, will have little clinical consequence to the patient. Most of these injuries will heal well without painful sequelae, whether or not the spine is immobilized. Other potential harmful outcomes from a missed fracture include chronic pain, deformity, and, most importantly, a delayed injury to the spinal cord and/or adjacent nerve root. Of available reports on missed spinal injuries, few distinguish among these po-

Figure 3. A, Lateral c-spine radiograph shows relatively normal alignment of the occiput on C1 lateral masses, but the view is obscured by earrings. B, Sagittally reconstructed CT clearly shows that the occipital condyle is separated and pushed forward, relative to the lateral mass of C1. be missed on plain radiographs,6,7 particularly fractures of the upper cervical spine. The present study did not examine patients with stable missed fractures or even Figure 5. A, Lateral lumbar spine radiograph reveals L1L2 fracture dislocation with relative anterolisthesis of L1 on L2 and a fracture of unstable fractures without neurologic deﬁcits. the anterosuperior corner of the L2 vertebral body. B, Postoperative There are several potential consequences of a missed lateral lumbar spine radiograph shows restoration of alignment after fracture or subluxation. Most missed fractures, particu- pedicle screw instrumentation was placed from T11 to L3. 456 Spine • Volume 31 • Number 4 • 2006

Figure 6. A, Lateral c-spine radiograph on admission illustrates a subtle listhesis at C5C6 with otherwise relatively good alignment on supine films. B, On mobilization after “spinal clearance,” the patient had a C5 quadriplegia and died directly as result of the missed injury. Imaging studies at injury revealed a high-grade listhesis with bilateral jumped facets. tential adverse events. Furthermore, to our knowledge, tients with such injuries were deemed to have a cleared no reports have focused on the patient population that spine and yet presented with a delayed catastrophic in- has an adverse neurologic event as a result of a missed jury.15 A closed head injury can significantly complicate spinal injury. the task of spinal clearance as one loses the ability to The incidence of missed spinal injuries resulting in a determine if the patient is having spine related pain and neurologic deficit is unknown, and is believed by most precludes performing an accurate neurologic examina- trauma surgeons and radiologists to be low. On the other tion. In our study, at least 25% of our patients had a hand, most spine surgeons working at large trauma cen- significant closed head injury (n ϭ 6/24). The respective ters have treated such patients and have an excellent admission Glasgow Coma Score of each patient was 3, 7, recall of such cases because they are at most times pre- 11, 13, 13, and 14 of a possible 15 points, which includes ventable injuries. Should a spine surgeon or group mem- verbal, eye, and motor assessment. In each case, during ber have forgotten a case, this would be reflected in the the course of hospitalization, the patient regained con- study as an underreporting of the true incidence of this sciousness and/or cerebral function, and was subse- problem. We determined the incidence of missed spine quently noted to have neurologic deterioration caused by injuries with a neurologic deficit relative to total spine a spinal cord injury. fractures and total trauma patients to be 0.21% and In this study, one of most important reasons for a 0.0025%, respectively. Many patients in our study were missed injury was insufficient imaging studies. What is elderly. The average age of our patient population (i.e., meant by insufficient? Some patients were cleared inap- 50 years) was significantly older than national stan- propriately on clinical grounds alone, and, therefore, dards.14 One potential reason for such this observation is some of these patients with missed injuries did not re- that superimposed degenerative changes may make the ceive any imaging. While others underwent plain radio- diagnosis of spinal injury more challenging. graphs alone. These imaging studies failed to detect a High-speed MVAs were the most common cause of a displaced fracture for a variety of reasons. A typical ex- cervical or thoracolumbar junction injury in our patient ample included shoulders obstructing the view of the population, which stresses the importance of considering cervicothoracic junction. Still another group of patients, mechanism of injury in “clearing” the spine. Patients particularly patients with associated closed head injury, with ankylosing spondylitis represent an extremely high- underwent adequate supine plain radiographs and high risk spine trauma patient population, and 2 of the pa- resolution CT of the entire cervical spine, and had dete- Neurologic Deterioration Secondary to Unrecognized Spinal Instability • Levi et al 457 rioration because a purely ligamentous injury went on to discretion of the treating physician. There were 2 pa- subluxation when the patient was mobilized. Such an tients, including the patient presented as case No. 2, who injury may have been prevented if carefully monitored serve to illustrate how the initial EAST protocol would flexion extension views or MRI was performed. Clearly, have missed the injury, while the Neurosurgery and the misread imaging and poor quality images were other im- current EAST guidelines would have gone on to image portant contributors to the cause of a missed injury, further this obtunded patient. MRI in case No. 2 was however, each are arguably more preventable than inad- able to detect the purely ligamentous injury (Figure 4). equate imaging studies. One would suspect that the revised EAST guidelines,5 No single radiographic study can adequately exclude which includes c-spine flexion and extension views, cervical spinal injury in all symptomatic patients. A would have also diagnosed this patient before having a 3-view cervical spine series supplemented with CT neurologic injury. The EAST group5 performed a meta- through areas that are difficult to visualize and/or are analysis (227 patients) in which no spinal cord injuries “suspicious” will detect the vast majority of spinal inju- were caused by the flexion/extension studies. ries and is considered the minimum combination of stud- In this multicenter study of large trauma hospitals, we ies required for clearance of the cervical spine in the found that missed spinal injuries with resultant neuro- symptomatic patient.4,11 These recommendations stem logic sequelae had a higher than expected occurrence. from the development of evidence-based guidelines for High-energy trauma, older age, closed head injury, and the treatment of acute spine and spinal cord injuries. patients with insufficient imaging are at highest risk. Ra- In the obtunded patient with a normal 3-view radio- diographic studies must be adequate and of good quality, graph series and appropriate CT of the cervical spine, the and should be supplemented by adjunctive tests when incidence of significant spine injury is less than 1%. there is any doubt as to the stability of the spine. Based on mechanism of injury and clinical judgment, the cervical spine in select patients may be considered cleared without further study. In the remainder of cases, Key Points flexion/extension performed under fluoroscopic visual- ● Neurologic deterioration from a missed spinal ization appears to be safe and effective for excluding injury continues to occur in the trauma setting. significant ligamentous injury, with a reported negative ● Insufficient imaging studies is the most common 13,16–19 predictive value of more than 99%. Patients who reason for a missed injury. are unable to cooperate with active flexion/extension ra- ● Adherence to published guidelines for spinal diographs because of pain or muscle spasm may be main- clearance will reduce the risk of such injuries. tained in a cervical collar until they are able to cooperate or may be studied with MRI. Acknowledgments MRI represents another option for clearance of the The authors thank Dr. Dan Resnick for reviewing the spine in this patient population, and negative MRI manuscript and David Wang, PhD, for his assistance within 48 hours of injury appears to eliminate effectively with manuscript submission. the likelihood of a significant ligamentous injury.20–23 However, the significance of a positive MRI study is cur- rently unclear.24 Indiscriminate MRI evaluation of the spine in the setting of trauma will result in a large num- References 25 ber of false-positive examinations, and the conse- 1. MacDonald RL, Schwartz ML, Mirich D. Diagnosis of cervical spine injury quences of prolonged unnecessary immobilization in the in motor vehicle crash victims: How many x-rays are enough? J Trauma 1990;30:392–7. obtunded patient are not insignificant. 2. Davis JW, Phreaner DL, Hoyt DB, et al. The etiology of missed cervical spine The biggest difference between the EAST guidelines injuries. J Trauma 1993;34:342–6. and the Neurosurgery recommendation standards and 3. Grossman MD, Reilly PM, Gillett T, et al. National survey of the incidence of cervical spine injury and approach to cervical spine clearance in U.S. trauma options is in the treatment of trauma patients with an centers. J Trauma 1999;47:684–90. “altered level of consciousness.” Initially, the EAST 4. Pasquale M, Fabian TC. Practice management guidelines for trauma from the guidelines would allow for clearance of the spine with Eastern Association for the Surgery of Trauma. J Trauma 1998;44:941–57. 5. Eastern Association for the Surgery of Trauma Web site. Available at: . “adequate 3-view plain radiographs (CT supplementa- 6. Link TM, Schuierer G, Hufendiek A. Substantial head trauma: Value of tion as necessary) and thin cut axial CT images through routine CT examination of the cervicocranium. Radiology 1995;196:741–5. C1 and C2.”4 Subsequent recommendations,5 which re- 7. Blacksin MF, Lee HJ. Frequency and significance of fractures of the upper cervical spine detected by CT in patients with severe neck trauma. AJR Am J viewed several recent publications on ligamentous insta- Roentgenol 1995;165:1201–4. 16,17,26 bility after trauma, included the use of “flexion/ 8. Schenarts PJ, Diaz J, Kaiser C, et al. Prospective comparison of admission extension lateral cervical spine fluoroscopy with static computed tomographic scan and plain films of the upper cervical spine in trauma patients with altered mental status. J Trauma 2001;51:663–8. images obtained at the extremes of flexion and exten- 9. Barba CA, Taggert J, Morgan AS, et al. A new cervical spine clearance sion” in patients with altered mental status, even when protocol using computed tomography. J Trauma 2001;51:652–7. plain radiographs and CT were negative. The Neurosur- 10. Levi ADO: Approach to the patient with spine trauma. In: Winn HR, ed. Youmans Neurological Surgery. 5th ed. Philadelphia, PA: Saunders; 2003: gery recommendation suggests further imaging to in- 4869–84. clude dynamic flexion and extension views or MRI at the 11. Hadley MN, Walters B. Radiographic assessment of the cervical spine in 458 Spine • Volume 31 • Number 4 • 2006

symptomatic trauma patients in guidelines for the management of acute 19. Patton JH, Kralovich KA, Cuschieri J. Clearing the cervical spine in victims cervical spinal injuries. Neurosurgery 2002;50:S36–43. of blunt assault to the head and neck: What is necessary? Am Surg 2000;66: 12. Ghanta MK, Smith LM, Polin RS, et al. An analysis of Eastern Association 326–30. for the Surgery of Trauma practice guidelines for cervical spine evaluation in 20. Lee SL, Sena M, Greenholz SK, et al. A multidisciplinary approach to the a series of patients with multiple imaging techniques. Am Surg 2002;68: development of a cervical spine clearance protocol: Process, rational, and 563–7. initial results. J Pediatr Surg 2003;38:358–62. 13. Lockey AS, Handley R, Willet K. ‘Clearance’ of cervical spine injury in the 21. Brooks RA, Willett KM. Evaluation of the Oxford protocol for total spinal obtunded patient. Injury 1998;29:493–7. clearance in the unconscious trauma patient. J Trauma 2001;50:862–7. 14. Nobunaga AI, Go BK, Karunas RB. Recent demographic and injury trends in 22. Frank JB, Lim CK, Flynn JM, et al. The efficacy of magnetic resonance people served by the Model Spinal Cord Injury Care Systems. Arch Phys Med imaging in pediatric cervical spine clearance. Spine 2002;27:1176–9. Rehabil 1999;80:1372–82. 23. Geck MJ, Yoo S, Wang JC. Assessment of cervical ligamentous injury in 15. Finkelstein JA, Chapman JR, Mirza S. Occult vertebral fractures in ankylos- trauma patients using MRI. J Spinal Disord 2001;14:371–7. ing spondylitis. Spinal Cord 1999;37:444–7. 24. Horn EM, Lekovic GP, Feiz-Erfan I, et al. Cervical magnetic resonance 16. Davis JW, Parks SN, Detlefs CL. Clearing the cervical spine in obtunded imaging abnormalities not predictive of cervical spine instability in traumat- patients: The use of dynamic fluoroscopy. J Trauma 1995;39:435–8. ically injured patients. J Neurosurg Spine 2004;1:39–42. 17. Sees DW, Rodriguez Cruz LR, et al. The use of bedside fluoroscopy to 25. Benzel EC, Hart BL, Ball PA. Magnetic resonance imaging for the evaluation evaluate the cervical spine in obtunded trauma patients. J Trauma 1998;45: of patients with occult cervical spine injury. J Neurosurg 1996;85:824–9. 768–71. 26. Ajani AE, Cooper DJ, Scheinkestel CD. Optimal assessment of cervical spine 18. Cox MW, McCarthy M, Lemmon G, et al. Cervical spine instability: Clear- trauma in critically ill patients: A prospective evaluation. Anaesth Intensive ance using dynamic fluoroscopy. Curr Surg 2001;58:96–100. Care 1998;26:487–91.