Cervical Spine Computed Tomography Scans Research Articles

Research into the anatomy of the subaxial cervical pedicle for ensuring screw insertion safety.

The study aimed to determine the optimal entry points and trajectories for posterior subaxial cervical pedicle screw (CPS) fixation. Computed tomography (CT) and Mimics software were used to evaluate the subaxial cervical pedicle in 42 cervical spine CT scans. The width of the cervical pedicle was measured and compared at medial angulations of 30°, 35°, 40°, 45°, 50°, 55°, and 60° relative to the midline sagittal plane. Based on an observational examination of the positions of all cervical 3-dimensional models and screws, the proposed entry point for C3-7 CPS was analyzed. Although the variations in C3-6 pedicle width (PW) among 45°, 50°, and 55° were not statistically significant, they were significantly larger than the differences among 30°, 35°, 40°, and 60° angles (P < .05). The differences in C7 PW between the 30°, 35°, 40°, and 45° angles were not statistically different even though the 30°, 35°, 40°, and 45° angles were significantly bigger. (P < .05). The proposed entry point for C3-7 CPS was below the junction of the lateral and lower borders of the superior articular process joint surface. The entry point for C3-7 levels was below the junction of the lateral and lower borders of the superior articular process joint surface. The optimal medial angulation for the posterior C3-6 CPS was 45°-55° and that for the posterior C7 CPS was 30°-45°. The sagittal angle of the posterior C3-7 CPS was parallel to the corresponding upper endplate.

Variation in Cervical Pedicle Morphology: Important Considerations for Posterior Cervical Procedures.

Safe posterior cervical spine surgery requires in-depth understanding of the surgical anatomy and common variations. The cervical pedicle attachment site to the vertebral body (VB) affects the location of exiting nerve roots and warrants preoperative evaluation. The relative site of attachment of the cervical pedicle has not been previously described. To describe the site of the pedicle attachment to the VB in the subaxial cervical spine. Cervical spine computed tomography scans without any structural, degenerative, or traumatic pathology as read by a board-certified neuroradiologist during 2021 were reviewed. Multiplanar reconstructions were created and cross-registered. The pedicle's attachment to the VB was measured relative to the VB height using a novel calculation system. Fifty computed tomography scans met inclusion criteria yielding 600 total pedicles between C3-T1 (100 per level). The average patient age was 26 ± 5.3 years, and 21/50 (42%) were female. 468/600 (78%) pedicles attached in the cranial third of the VB, 132/600 (22%) attached in the middle third, and 0 attached to the caudal third. The highest prevalence of variant anatomy occurred at C3 (36/100 C3 pedicles; 36%). In the subaxial cervical spine, pedicles frequently attach to the top third of the VB, but significant variation is observed. The rate of variation is highest at C3 and decreases linearly with caudal progression down the subaxial cervical spine to T1. This is the first report investigating this morphological phenomenon.

Assessment of cervical spine CT scans by emergency physicians: A comparative diagnostic accuracy study in a non-clinical setting.

ObjectivesTo determine and compare the diagnostic accuracy of assessing injuries on cervical spine computed tomography (CT) scans by trained emergency physicians and radiologists, both in a non‐clinical setting.MethodsIn this comparative diagnostic accuracy study, 411 cervical spine CT scans, of which 120 contained injuries (fractures and/or dislocations), were divided into 8 subsets. Eight emergency physicians received focused training and assessed 1 subset each before and after training. Four radiologists assessed 2 subsets each. Diagnostic accuracy between both groups was compared. The reference standard used was a multiverified data set, assessed by radiologists, neurosurgeons, and emergency physicians. The neurosurgeons also classified whether an "injury in need of stabilizing therapy" (IST) was present.ResultsPosttraining, the emergency physicians demonstrated increased sensitivity and specificity for identifying cervical spine injuries compared to pretraining: sensitivity 88% (95% confidence interval [CI] 80% to 93%) versus 80% (95% CI 72% to 87%) and specificity 89% (95% CI 85% to 93%) versus 86% (95% CI 81% to 89%). When comparing the trained emergency physicians to the group of radiologists, no difference in sensitivity was found, 88% (95% CI 80% to 83%); however, the radiologists showed a significantly higher specificity (P < 0.01): 99% (95% CI 96% to 100%). In the 12% (15 scans) with missed injuries, emergency physicians missed more ISTs than radiologists, 6 versus 4 scans; however, this difference was not significant (P = 0.45).ConclusionAfter focused training and in a non‐clinical setting, no significant difference was found between emergency physicians and radiologists in ruling out cervical spine injuries; however, the radiologists achieved a significantly higher specificity.

Radiologic evaluation of congenital anomalies of anterior and posterior arch of atlas in Omani subjects

The atlas (C1) is known to present congenital anomalies in its anterior and posterior arches. The reported incidence of C1 anomalies is varied among the ethnic groups. We sought to determine the prevalence and various existing variations of C1 arch congenital anomalies in Omani subjects. This study was carried out by reviewing the cervical spine computed tomography scans of all the patients who had been referred to the Radiology Department, Sultan Qaboos University Hospital. Descriptive statistics and chi-square test were employed to analyse the data. A total of 663 subjects aged ≥18 years were included in the present study. Overall prevalence of C1 arch anomalies was 4.37% with 4.07% of isolated posterior arch anomalies, 0.3% of combined anterior and posterior arch anomalies. Among isolated posterior arch anomalies, type A and type B posterior arch defects were found in 3.77% and 0.3% of cases, respectively. Atlanto-occipital assimilation was noted in one case of total study subjects. The prevalence rate of C1 arch anomalies is relatively high in Omani subjects. The baseline data of C1 arch anomalies reported in the present study has a great impact on clinical practice, due to the fact that studying and evaluating the types of congenital anomalies helps in their accurate diagnosis and early intervention.

Diagnostic Accuracy and Prognostic Significance of Point-Of-Care Ultrasound (POCUS) for Traumatic Cervical Spine in Emergency care setting: A Comparison of clinical outcomes between POCUS and Computed Tomography on a Cohort of 284 Cases and Review of Literature.

Background:The cervical spine is injured in approximately 3% of major trauma patients, and 10% of patients with serious head injury. Therefore, clearance of the cervical spine in multitrauma patients is a critically important task. This is particularly important, considering that there is a positive correlation between a Glasgow Coma Scale of <14 and cervical spine injury. Radiography is not sensitive enough to rule out cervical spine injury, especially as radiography done in the trauma setting is usually technically unsatisfactory.Objective:The current study aims to assess the diagnostic accuracy and prognostic significance of using bedside point-of-care ultrasound (POCUS) in traumatic cervical spine injuries compared to computed tomography (CT) as the reference standard.Materials and Methods:This comparative study enrolled 284 patients with severe multiple trauma at a tertiary care center between July 2017 and March 2020. The inclusion criteria included an indication of cervical spine CT scan, satisfaction of patients with participation in the study, and the lack of history of injury and severe traumatic events. The exclusion criteria were the history of a previous cervical spinal trauma, spondylosis, scoliosis, spinal tuberculosis, degenerative vertebral changes, and patients who refused to give consent to participate in research or CT scanning. The data were analyzed by SPSS software, and sensitivity, specificity, and positive predictive value (PPV)/negative predictive value (NPV) were determined based on CT findings.Results:The best window for the cervical spine was through the anterior triangle using the linear array probe (6–13 MHz). POCUS had a sensitivity of 78.5%, specificity of 98.4%, PPV of 93.2%, NPV of 92.8%, and accuracy of 93.2% in detecting all types of spinal injuries in comparison with CT scan as the standard modality. POCUS had a sensitivity of 100%, specificity of 92.3%, PPV of 62.3%, NPV of 100%, and accuracy of 91.7% in cases with the movement of injured particles. POCUS had a sensitivity of 32.2%, specificity of 100%, PPV of 100%, NPV of 91.4%, and accuracy of 90.8% in detecting the fracture of transverse process. POCUS had a sensitivity of 36.1%, specificity of 100%, PPV of 100%, NPV of 98.1%, and accuracy of 98.4% in ≤14-year age multitrauma patients. In comparison, the current study achieved a sensitivity of 79.4%, specificity of 95.7%, PPV of 92.1%, NPV of 86.3%, and accuracy of 88.6% in >14-year age multitrauma patients.Conclusion:POCUS for cervical spine is feasible using portable ultrasound machine and by neurosurgeons/radiologists/emergency physicians with basic training. It holds great potential in resource-starved settings and in unstable patients for ruling out unstable cervical spine injuries and injuries associated with the movement of fractured or dislocated particles. POCUS examination of the cervical spine was possible in the emergency setting and even in unstable patients and could be done without moving the neck. Future studies, ideally conducted as randomized control trials, are required to establish training and education standards, and to assess the feasibility and safety of POCUS as an alternative to radiography.

Traumatic shock and altered mentality following motor vehicle accident

Traumatic atlanto-occipital dislocation is associated with significant mortality and morbidity. We present an 18-year-old female who visited the emergency department after a motor vehicle accident. A cervical spine computed tomography scan showed the postero-inferior atlanto-occipital dissociation and several diagnostic methods coincided with the diagnosis of atlanto-occipital dislocation.

Congenital Osseous Anomalies of the Cervical Spine: Occurrence, Morphological Characteristics, Embryological Basis and Clinical Significance: A Computed Tomography Based Study.

Study DesignObservational retrospective computed tomography (CT) based study.PurposeTo analyze the congenital anomalies of the cervical spine, their morphological variations and their clinical significance.Overview of LiteratureStudies published to date have focused mainly on upper cervical anomalies; no study has comprehensively reported on anomalies of both the occipitocervical and subaxial cervical spine.MethodsNine hundred and thirty cervical spine CT scans performed in Ganga Hospital, Coimbatore, India between January 2014 and November 2017 were screened by two independent observers to document anomalies of both the upper and lower cervical spine. CT scans conducted for infection, tumor, and/or deformity were excluded. Different morphological variations, embryological basis, and clinical significance of the anomalies were discussed.ResultsOf the 930 CT scans screened, 308 (33.1%) had congenital anomaly. Of these, 184 (59.7%) were males and 124 (40.2.7%) were females, with a mean age of 44.2 years (range, 14–78 years). A total of 377 anomalies were identified, with 69 cases (7.4%) having more than one anomaly. Two hundred and fifty (26.8%) anomalies of the upper cervical region (occiput to C2–C3 disk space) were identified, with the most common upper cervical anomalies being high-riding vertebral artery (108 cases, 11.6%) and ponticulus posticus (PP) (75 cases, 8%). One hundred and twenty seven (13.6%) anomalies of the lower cervical spine (C3–C7) were noted, of which double foramen transversarium was the most common anomaly observed in 46 cases (4.8%).ConclusionsWe found that 33.1% of CT scans had at least one congenital anomaly. Some anomalies, such as abnormal facet complex and arch anomalies, have to be differentiated from fractures in a trauma patient. Other anomalies, like PP, have to be looked for during preoperative planning to avoid complications during surgery. Therefore, knowledge of these anomalies is important as different anomalies have different clinical courses and management.

Frequency and Type of Ponticulus Posticus and Lateralis in a Chinese Population: A CT-Based Analysis of 4047 Cases.

To investigate the prevalence and type of ponticulus posticus (PP) and ponticulus lateralis (PL) in the Chinese population by analyzing computed tomography (CT) scans, and to uncover the pathogenesis of PP and PL. A total of 4,047 cases were included in this study. We evaluated cervical spine CT scans with three dimensional reconstructions and collected age, gender, and presence of PP and PL in each case. If either or both were present, location and type were recorded. The overall prevalence of PP was 8.01%. The age of patients with PP was significantly higher than those without. Men had a higher prevalence of PP than women. The presence of PP was more common on the left side than the right. According to our previous classification, the most common type of a PP was AC (32.41%), followed by CC (20.06%) and CA (16.98%). The overall prevalence of PL was 4.67%, with no differences between age groups, genders or by location. The most common type of PL was AC (43.92%), followed by CA (35.98%) and CC (20.11%). The prevalence of PP and PL occurring in the same patient was 1.26%. Based on cervical spine CT scans of 4,047 Chinese patients, we found that the prevalence of PP and PL were 8.01% and 4.67%, respectively. PP was more common in older patients, which strongly suggests that PP may be a congenital osseous anomaly of the atlas that mineralizes during aging.

Incidental findings on cervical spine computed tomography scans: overlooked and unimportant?

Imaging of the cervical spine for trauma or degenerative disease includes multiple areas of the head and neck that may harbor incidental findings. We sought to determine the incidence of common "incidentalomas" on cervical spine CT scans, their importance, and how often these lesions are mentioned in reports. We retrospectively reviewed the cervical spine CTs and reports of all patients scanned between October 2017 and January 2018 for Tornwaldt cysts (TC), thyroglossal duct cysts and remnants (TGDC), laryngoceles (LC), pharyngoceles (PC), carotid artery calcified stenosis (CACS), and aberrant right subclavian arteries (ARSA). Descriptive statistics were performed, and the incidence of cancers (in PC and LCs) and strokes (in high-grade carotid stenosis) was assessed. Among 2116 patients, the incidences of findings were TC 6.6% (138/2100), TGDC 6.3% (122/1770), LC 9.4% (197/2100), PC 6.4% (135/2100), CACS 4.7% (100/2114), and ARSA 0.86% (18/2097). Of the 2116 patients studied, 600/2116 (28.3%) had at least one incidental finding. Only 2.9% (20/701) of incidentalomas were mentioned in the official reports. Cervical incidentalomas vary in rates from ARSA (0.86%) to LC (9.4%). They are rarely mentioned in radiologists' reports. Whether improved vigilance and reporting of these incidentalomas would benefit patient care should be explored.

Friday, September 28, 2018 4:05 PM–5:05 PM abstracts: new concepts: cervical spine: 245. Risk of atlantooccipital joint injury during C1 pedicle screw insertion: a CT-based morphology study of atlas

BACKGROUND CONTEXT C1 pedicle screw technique is increasingly popular for atlantoaxial screw-rod fixation. Many authors have reported anatomic studies for C1 pedicle screw insertion. Most of them focused on whether the pedicle screw would injury transverse foramen, vertebral groove and spinal dura. No study evaluates the risk of atlantooccipital joint injury during C1 pedicle screw insertion yet. PURPOSE To evaluate the risk of atlantooccipital joint injury when inserting C1 pedicle screw and analyse the related anatomic factors. STUDY DESIGN/SETTING A CT-based morphology study. PATIENT SAMPLE Two hundred study units. OUTCOME MEASURES Atlantooccipital joint penetration by the pedicle screw was defined as atlantooccipital joint injury. METHODS One hundred thin-cut upper cervical spine computed tomography (CT) scans which met our inclusion criteria were acquired. The sagittal plane of the planned C1 pedicle screw trajectory was reconstructed. Each sagittal plane was considered as a single unit. And then a 3.5-mm-diameter cylinder was draw to simulate a 3.5-mm-diameter pedicle screw inserting into atlas on each sagittal plane. Atlantooccipital joint penetration by the pedicle screw was defined as atlantooccipital joint injury. Those sagittal planes with atlantooccipital joint injury were carefully studied and the morphology of the atlas was observed and analyzed. RESULTS Two hundred study units were obtained from one hundred upper cervical spine CT scans. Virtual C1 pedicle screw insertion showed that atlantooccipital joint injury occurred in thirty-two units (16%) with bilaterally in eleven patients and unilaterally in ten patients. Over-concave superior articular facet of atlas, high junction of C1 pedicle and C1 lateral mass, and over-cephalad incline of C1 pedicle were observed in units with atlantooccipital joint injury. CONCLUSIONS Two hundred study units were obtained from one hundred upper cervical spine CT scans. Virtual C1 pedicle screw insertion showed that atlantooccipital joint injury occurred in thirty-two units (16%) with bilaterally in eleven patients and unilaterally in ten patients. Over-concave superior articular facet of atlas, high junction of C1 pedicle and C1 lateral mass, and over-cephalad incline of C1 pedicle were observed in units with atlantooccipital joint injury.

Comparison of Three Different Options for C7 Posterior Vertebral Anchor in the Indian Population-Lateral Mass, Pedicle, and Lamina: A Computed Tomography-Based Morphometric Analysis.

Study Design Radiological cohort study.PurposeThe options of posteriorly stabilizing C7 vertebra include using lateral mass, pedicle or lamina, as bony anchors. The current study is a computed tomography (CT)-based morphometric analysis of C7 vertebra of 100 Indian patients and discusses the feasibility of these different techniques.Overview of LiteratureC7 is a peculiar vertebra with unique anatomy, which poses challenges for each of these fixation modalities. There are no reports available in the literature, which discuss and compare the feasibility of diverse posterior C7 fixation techniques in Indian population.MethodsWe included 100 consecutive cervical spine CT scans of Indian patients performed between July 2016 and September 2016. We excluded CT scans with any significant congenital anomaly or other pathological lesions of C7 and patients with non-Indian ethnicity. Regarding screw placement, we assessed and studied various dimensions of the C7 lateral mass, pedicles, and laminae in relevant sections.ResultsThe mean age of our patients was 49.5±16.1 years. We included 56 male and 44 female patients. The mean anteroposterior and mediolateral dimensions of the lateral mass were 11.38±1.76 and 12.91±1.82 mm, respectively. The mean length of the lateral mass screw (Magerl technique) was 12.17±1.9 mm; 92% of patients could accommodate a lateral mass screw at least 10-mm long (unicortical), whereas 48% could accommodate a screw (unicortical) longer than 12 mm. Foramen transversarium was found in 30.5% of lateral masses. The mean outer and inner cortical widths of the pedicles were 6.5±0.71 mm and 3.72±0.61 mm, respectively. Approximately 58% of pedicles could accommodate 3.5-mm screws (based on the inner cortical pedicle width). The outer cortical and inner cortical widths of the laminae were 6.21±1.2 mm and 3.23±0.9 mm, respectively. Subsequently, 37% of the laminae could accommodate 3.5-mm screws. The mean angle of intralaminar screw trajectory was 50.7°±5.1°, and the mean length of the intralaminar screw was 32.6±3.05 mm. In addition, 96.4% and 60.7% of male patients could accommodate lateral mass screws longer than 10 mm and 12 mm, respectively. However, only 86.4% and 31.8% of female patients could accommodate 10- and 12-mm long lateral mass screws, respectively. Furthermore, 75% of male patients and 36% of female patients had pedicles that could accommodate 3.5-mm diameter screws, and 48.2% of male patients had laminae that could accommodate 3.5-mm screws; however, only 22.7% of female patients could accommodate 3.5-mm laminar screws.Conclusions Based on our CT-guided morphometric analysis, 92% and 48% of Indian patients could accommodate at least 10- and 12-mm long lateral mass screws, and 58% of pedicles and 37% of laminae could accommodate 3.5-mm screws. Thus, lateral mass screws (between 10- and 12-mm long) seem to be the safest feasible option for C7 fixation. In case of the need for an alternative mode of stabilization (pedicle or intralaminar screw), particularly in female patients, careful preoperative planning with a CT scan is of utmost importance.

How Common Is the Ponticulus Posticus?: A Computed Tomography Based Analysis of 2917 Patients.

A computed tomography (CT) study of the morphology of the C1 vertebra. Is to determine the prevalence of ponticulus posticus (PP) by analyzing CT scans performed on a large, diverse population in the northeast United States. This study also proposes a CT-based classification system both to aid in unifying the description of PP, and to aid in future research. The prevalence of PP varies from 5% to 68% in published studies. There may be geographic variation in the prevalence of PP. Our objective was to establish the prevalence of PP in the general population, and to develop a comprehensive classification system to describe PP. We evaluated cervical spine CT scans performed on patients in the emergency room of a level I trauma center over a 1-year period (January 1, 2014-December 31, 2014). The CT images were evaluated for the presence of a PP, and if present the following demographic data were collected: age, sex, race/ethnicity, and body mass index (BMI). We propose a novel classification system to standardize the description of PP identified on CT scan. Two thousand, nine hundred and seventeen cervical spine CT scans were reviewed in this study. The prevalence of PP was 22.5%. Men had a higher prevalence of PP than women (53.5% male vs. 46.5% female P ≤ 0.01). When compared with the overall population, African-Americans were more likely to have a PP (P ≤ 0.01), while Caucasian patients were less likely (P ≤ 0.01). The novel classification consisted of a two letter designation for each patient, with the first letter denoting the right sided arch and the second letter the left sided arch. Each side of the arch described as an A, B, or C type. The A type had no presence of a PP, B type had in incomplete PP, and C type had a complete PP. The most common type of a PP was CC encompassing 25% of the patients. The presence of a PP was more common in the left sided arch than the right side (B and C type Left 89.2% vs. B and C type Right 84.7%, P = 0.02). We found a 22.5% prevalence of PP in 2917 patients undergoing a cervical spine CT. This is the largest study to evaluating the prevalence of PP. 4.

Computerized Tomography-Based Morphometric Analysis of Subaxial Cervical Spine Pedicle in Asymptomatic Indian Population.

The purpose of this study was to analyze morphometry of the subaxial cervical spine pedicles in an Indian population based on computed tomography (CT), and thus assess the safety and feasibility of cervical pedicle screw in the subaxial cervical spine. CT scans of 500 subaxial cervical spine vertebrae were analyzed from 100 patients presenting to our institution and undergoing cervical spine CT scan for an unrelated cause as part of ATLS protocol. Pedicle width (PW), pedicle axis length (PAL), pedicle transverse angulation (PTA), and lateral pedicle distance (LPD) were calculated on axial CT scans, and pedicle height (PH), pedicle length (PL), superior pedicle distance (SPD), and pedicle sagittal angulation (PSA) were calculated on sagittal CT scans. The mean PW ranged from 4.3 mm at C3 to 5.7 mm at C7. Mean PH ranged from 5.5 mm at C3 to 6.1 mm at C7. Mean PTA ranged from 44.5° at C3 to 37.1° at C7. PSA ranged from 16.65° at C3 to 3.29° at C7. Mean LPD ranged from 1.6 mm at C3 to 3.4 mm at C6. Mean SPD ranged from 3.5 mm at C3 to 1.15 mm at C7. Mean PAL ranged from 29.6 mm at C3 to 33.04 mm at C7. Mean PL ranged from 5.2 mm at C3 to 5.78 mm at C7. Our CT-based morphometric study confirms that cervical pedicle screw placement is possible in most of the Indian population except at C3 in females. A thorough understanding of pedicle anatomy with proper CT-based preoperative planning can mitigate the risk associated with pedicle screw placement in subaxial cervical spine.

Radiologic Analysis of C2 to Predict Safe Placement of Pedicle Screws.

Preoperative assessment of C2 pedicle morphology is critical to safe pedicle screw placement. To avoid iatrogenic injury, complex digital templating software has been introduced; however, this technology may not be available in many centers. We report a technique for preoperative assessment of C2 pedicle screw placement safety based upon 2-dimensional sagittal computed tomography (CT) scan images and verify its utility in clinical practice. A total of 46 consecutive patients underwent cervical spine CT scans between 2005 and 2011. The C2 pedicle morphology was assessed on sagittal CT imaging by 5 independent reviewers to determine the feasibility and risk associated with pedicle screw placement. Thirty consecutive patients underwent C2 pedicle screw placement and were followed clinically for a minimum of 2 years. The ability to place a screw was noted, and accuracy of screw placement was assessed postoperatively by CT scan. The CT scan analysis demonstrated that 11% (5/46) of patients had sufficient pedicle size bilaterally to allow safe placement of long pedicle screws with a low risk of vertebral artery injury, whereas 15% (7/46) were considered a high risk bilaterally. Screw placement was deemed low risk in 28%, moderate risk in 38%, and high risk in 34%. Excellent intraobserver reliability and good interobserver reliability was observed. Clinically, 18 of 20 (90%) low-risk and 21 of 24 (88%) moderate-risk pedicle screws were placed safely versus 5 of 16 (31%) high-risk pedicle screws (P < .001). Using the described technique for evaluating the C2 pedicle via sagittal CT scan images allows for safe and reliable pedicle screw placement without relying upon complex digital templating software, which may have limited availability. II. This study aids in the surgical decision-making behind the placement of C2 pedicle screws using CT scans without reliance upon complex digital templating software.

"Inline" Axial Reconstructed CT Scans Provide a Significantly Larger Assessment of C2 Pedicle Diameter for Screw Placement Compared With "Standard" Axial Scans: Implications for Surgical Planning.

Radiologic analysis. The objective was to compare C2 pedicle diameter and screw feasibility on reconstructed axial computed tomography (CT) cuts created "Inline" (IL) with the intended pedicle screw tract versus unaltered "Standard" (STD) axial cuts. Axial CT cuts through the C2 pedicle are commonly evaluated when planning pedicle screw fixation as medial aberrancies of the vertebral artery can significantly narrow pedicle diameter. STD axial CT cuts provided by radiology departments are typically formatted orthogonal to the long axis of the neck or the vertical plumb, which is often not IL with the axis of the intended C2 pedicle screw tract. A total of 89 cervical spine CT scans obtained by a single radiology department over 2 years (35 male, 54 female; mean age 64.9 y) were reviewed. STD axial cuts were not manipulated but were assessed as provided. IL axial cuts were created along the intended C2 pedicle screw tract using free, open-source DICOM viewer software. Inner and outer pedicle diameters were measured on axial cuts most closely approximating the isthmus of the intended tract. On STD cuts, the mean outer and inner pedicle diameters were 5.05±1.45 and 2.01±1.31 mm, respectively. By contrast, IL measurements yielded significantly larger outer and inner diameters: 5.85±1.78 and 2.68±1.47 mm (P<0.01). IL measurement predicted a higher number of pedicles amenable to insertion of a 3.5 mm screw with safety margins of 1 to 3 mm. Reformatted IL axial cuts through the intended path of C2 pedicle screws provide significantly larger assessments of C2 pedicle diameter than those obtained on STD cuts. IL measurements predict C2 screw insertion feasibility in a substantially higher number of pedicles. As assessment of IL cuts may alter surgical decision-making at no added cost or radiation exposure, we suggest that they be obtained whenever considering C2 pedicle screw placement.

Incidence of combined cranial and cervical spine injuries in patients with blunt minor trauma: are combined CT examinations of the head and cervical spine justified?

Background The use of computed tomography (CT) scans of the head and cervical spine has markedly increased in patients with blunt minor trauma. The actual likelihood of a combined injury of head and cervical spine following a minor trauma is estimated to be low. Purpose To determine the incidence of such combined injuries in patients with a blunt minor trauma in order to estimate the need to derive improved diagnostic guidelines. Material and Methods A total of 1854 patients were retrospectively analyzed. All cases presented to the emergency department and in all patients combined CT scans of head and cervical spine were conducted. For the following analysis, only 1342 cases with assured blunt minor trauma were included. Data acquisition covered age, sex, and presence of a head injury as well as presence of a cervical spine injury or both. Results Of the 1342 cases, 46.9% were men. The mean age was 65.6 years. CT scans detected a head injury in 116 patients; of these, 70 cases showed an intracranial hemorrhage, 11 cases a skull fracture, and 35 cases an intracranial hemorrhage as well as a skull fracture. An injury of the cervical spine could be detected in 40 patients. A combined injury of the head and cervical spine could be found in one patient. Conclusion The paradigm of the coincidence of cranial and cervical spine injuries should be revised in patients with blunt minor trauma. Valid imaging decision algorithms are strongly needed to clinically detect high-risk patients in order to save limited resources.

Trends in CT Request and Related Outcomes in a Pediatric Emergency Department

To study and to establish the overall trends of computed tomography (CT) use and associated outcomes in the pediatric emergency department (PED) at Royal Hospital, Oman, from 2010 to 2014. The hospital electronic medical record was retrospectively searched to find children (from birth to 12 years old) who had visited the PED and the number of CT requests between 1 January 2010 and 31 December 2014. The types of CT examinations ordered were analyzed according to anatomical location and were as follows; head, abdomen/pelvis, chest, cervical spine/neck, and others. There were a total of 67 244 PED visits during the study period, 569 of which received 642 CT scans. There was a remarkable rise in CT uses per 1000 visits from 7 in 2010 to 12 in 2014. There was a 56% hike in CT requests from 87 in 2010 to 175 in 2014 while the number of pediatric emergency visits rose by about 28% from 11 721 to 15 052. Although head CT scans were the most common, cervical spine CT scans had the highest rate of increase (600%) followed by the chest (112%), head (54%) and abdomen (13%). There were no significant changes in other CT scan requests. The cost of CT scans increased from $18 096 to $36 400 during the study period, which increased the average PED cost by about $2 per visit. The average time between a CT being requested and then performed was 1.24 hours. CT use in the pediatric emergency department has risen significantly at a rate that markedly exceeds the growth of emergency visits. This is associated with an increase in PED costs and longer waiting times.

Evaluation of Cervical Spine Clearance by Computed Tomographic Scan Alone in Intoxicated Patients With Blunt Trauma.

Current trauma guidelines dictate that the cervical spine should not be cleared in intoxicated patients, resulting in prolonged immobilization or additional imaging. Modern computed tomography (CT) technology may obviate this and allow for immediate clearance. To analyze cervical spine clearance practices and the utility of CT scans of the cervical spine in intoxicated patients with blunt trauma. We performed a prospective observational study of 1668 patients with blunt trauma aged 18 years and older who underwent cervical spine CT scans from March 2014 to March 2015 at an American College of Surgeons-verified Level I trauma center. Intoxication was determined by serum alcohol levels and urine drug screens. Physical examination and CT scan findings were evaluated for cervical spine injuries (CSI) and the incidence of missed injuries. Clinically relevant CSIs requiring cervical stabilization. The hypotheses formed prior to data collection were that cervical CT scans are sensitive and specific enough to diagnose CSIs that require stabilization and that normal CT scans are sufficient to clear CSIs in intoxicated patients. Of 1668 patients, 1103 (66.1%) were male, with a mean (SD) age of 49 (20) years and a mean (SD) Injury Severity Score of 10 (9). Vehicular (734 [44.0%]) and falls (579 [34.7%]) were the most common mechanisms for hospitalization. Intoxication was identified in 632 of 1429 of patients tested (44.2%; 425 [29.7%] by serum alcohol levels and 350 [24.5%] by urine drug screens). Half (316 [50.0%]) were admitted with cervical spine immobilization, and 38 (12%) of these were solely owing to the presence of intoxication. There were 65 abnormal CT scans (10.3%) in the intoxicated group. Among 567 normal CT scans, 4 (0.7%) had central cord syndrome found on initial physical examination, and 1 (0.2%) had a symptomatic unstable ligament injury that was misread as normal on CT scan but was abnormal on magnetic resonance imaging. The 316 patients kept in a cervical collar for intoxication had no missed CSIs but were kept immobilized for a mean (SD) of 12 (19) hours. Computed tomographic scans had an overall negative predictive value of 99.2% for patients with CSIs and a negative predictive value of 99.8% for ruling out CSIs that required immobilization or stabilization. In this study, alcohol or drug intoxication was common and resulted in significant delays to cervical spine clearance. Computed tomographic scans were highly reliable for identifying all clinically significant CSIs. Spine clearance based on a normal CT scan among intoxicated patients with no gross motor deficits appears to be safe and avoids prolonged and unnecessary immobilization.

CT Alone for Cervical Spine Clearance in Intoxicated Patients

Because computed tomography (CT) is considered insensitive for ligamentous injuries, many intoxicated patients with concern for cervical spine injury are kept in a cervical collar or undergo magnetic resonance imaging (MRI), even after a normal CT scan. Growing evidence questions whether truly unstable injuries are missed by modern CT. These researchers prospectively assessed rates of spinal injuries missed by modern cervical spine CT scans in 1668 …

Cervical Footprint Anthropometry in Indian Population: Implications on Design of Artificial Disc Replacement Devices.

Study DesignCross-sectional study.PurposeTo accurately measure the dimensions of cervical endplates based on computed tomography (CT) scans in Indian population and assess accuracy of match with currently available cervical disc prostheses.Overview of LiteratureThe dimensions of currently available cervical disc replacement implants are based on early published geometrical measurements of vertebrae endplates for Caucasian population. To author's knowledge, similar study has not been published for patients from Indian subcontinent.MethodsCT scans of cervical spine of patients from Indian subcontinent were collected and reviewed. Seventy patients (54 men and 16 women; aged 18–56 years with average of 37 years) who underwent CT scans of cervical spine were included in study. 3D CT scans of sub axial cervical spine (C3 to C7) were analyzed. The anterior-posterior (AP) and central mediolateral (CML) dimensions of superior and inferior endplates from C3 to C7 were measured using digital measuring system.ResultsA total of 560 endplates of 70 patients were included in the study. The AP diameter of cervical endplates ranged from 0.87 to 2.47 cm. The CML diameters ranged from 0.84 to 2.98 cm. For levels C3/C4 and C4/C5 for AP dimension Prestige-LP (90.5%) and Prodisc-C (89%) discs showed higher percentage of matching than Discover discs (58.5%). For CML diameter, Prestige-LP (69.5%), Prodisc-C (70%) and Discover (39.5%) discs showed almost similar matching with measured endplates. For levels C5/C6 and C6/C7 for AP dimension, Prestige-LP (67.25%), Prodisc-C (49.35%) and Discover (51.5%) discs showed similar matching. For CML diameter Prestige-LP (32%), Prodisc-C (27.5%) and Discover (42.2%) discs showed poor matching with measured endplates.ConclusionsThis study indicates need for redesign of cervical disc prostheses to match Indian patients. The collected anthropometric dimensions from this study may be used to design and develop indigenous artificial total disc replacement prosthesis and even cervical cages in India. With the present study being a small pilot study, the authors recommend anthropometric CT measurements in larger number of Indian patients in order to validate footprint dimensions for designing better-matched prosthesis.