Atlanto-occipital Dissociation Research Articles

Upper cervical spine instability systematic review: a bibliometric analysis of the 100 most influential publications.

Instability in the upper cervical spine, although rare, can be devastating. This spectrum of conditions includes occipitocervical instability, atlantoaxial instability and atlantoaxial rotatory displacement. Knowledge of the literature can provide better understanding of disease processes and management, and aid in clinical decision making. The objective of this study was to perform a bibliometric analysis to formulate a comprehensive review of the most cited publications. A systematic search of the literature was conducted using the Clarivate Web of Science database. The search query was '"Atlanto-occipital dislocation" OR "atlanto-occipital dissociation" OR "atlantoaxial rotatory displacement" OR "atlantoaxial instability"'. The top 100 articles based on frequency of citation were included in our study. Data extracted from articles included frequency of citation, year of publication, country of origin, journal of publication, level of evidence and article type. Our initial search yielded 257 results that met the criteria. Articles not pertaining to atlanto-occipital instability were removed. Citation frequency ranged from 15 to 195. The most cited article was "Traumatic Anterior Atlanto-Occipital Dislocation" published by Powers et al. in 1979. The most productive decade was 2000-2009 with 45 publications. All decades showed a progressive increase in the number of papers published except for 2010-2019. Overall, 19 countries contributed and the most productive was the United States (n=61). The articles found in our search were cited a total of 4,095 times (3,463 without self-citations) averaging 40.95 citations per publication. The goal of a bibliometric study is to assess trends in a specific field of study, provide evidence for the impact of an individual or field of study's research, and highlight potential areas for future research. While the number of citations does not necessarily reflect publication quality, it reflects overall influence based on recognition by peers in the field. Publications from the last 20 years have emphasized the use of newer technologies such as computed tomography (CT) and magnetic resonance imaging (MRI) to aid in diagnosis. Our study highlights the lack of high-level evidence articles and underscores that our understanding of these conditions in both pediatric and adult patients is maturing.

Survival rates in atlanto-occipital dissociation: a look at the past 20 years

Atlanto-occipital dissociation (AOD) has historically been considered a fatal injury. Recent small case series, however, have suggested that AOD injuries have become increasingly survivable. There has not been an adequately powered study that confirms this. The aim of this study is to assess whether the survival rate for patients with AOD increased over time. Retrospective case series. Patients with traumatic AOD identified from our Level 1 Trauma Center database. Mortality following traumatic AOD. Patients with traumatic AOD from 1996 to 2019 were retrospectively identified from our Level 1 Trauma Center database using International Classification of Diseases 9 and 10 codes. Patients were stratified into two cohorts- those diagnosed before August 1, 2015 and after. A total of 52 patients met our inclusion criteria and were analyzed. Mean age was 34.41 (11.71), with 34 (65.4) females, and 26 (50) Hispanics. Mean BMI was 28.13 (7.30), mean injury severity score was 40.79 (21.72), and mean Glasgow coma scale was 5.91 (4.72). Overall, 33 patients died (63.5%). The mortality rate before 2015 was 81.80%, this number dropped down to 50% for those who were treated post 2015 (p=.01). This study demonstrates that patients treated recently for AOD at a level 1 trauma center were more likely to survive than patients treated in the past at the same center. Possible reasons for the improved survival rate seen in this study include: increased awareness of AOD, improved diagnostic protocols with more uniform computed tomography based imaging, and advances in the care of these patients.

Unilateral atlanto-occipital injury: A case series and detailed radiographic description.

ContextAtlanto-occipital dissociation is a highly lethal ligamentous injury at the craniocervical junction (CCJ). Previous studies have described rare cases of milder forms of atlanto-occipital injury (AOI) which might be managed nonoperatively, but there is a paucity of literature on this subject.Aims:We retrospectively reviewed our institutional experience to characterize the injury patterns, treatments, and clinical courses of patients with unilateral AOI.Methods:We included patients with radiographic evidence of unilateral occipitocervical joint capsular disruption, distraction, or edema ± injury of the apical ligament, tectorial membrane, anterior atlanto-occipital membrane, posterior atlanto-occipital membrane, alar ligaments, or cruciate ligament. The long-term outcomes were gathered from medical records, and six patients were available for Neck Disability Index via phone call at the time of the study.Results:Eight patients were included in the study. The mean age was 45.1 years ± 26.5. Causes of trauma included motor vehicle collision for five patients (5/8, 62.5%), falls for two (2/8, 25), and assault for one (1/8, 12.5%). All patients had a widened condyle-C1 interval >2 mm. Three patients underwent occipitocervical fusion, one patient underwent atlantoaxial fusion, and another received subaxial fusions for other injuries. Three patients underwent no surgical intervention. All patients were seen at least once as an outpatient following hospital discharge. There were no delayed neurologic injuries or deaths.Conclusions:We propose that ligamentous injury at the CCJ functions more as a spectrum rather than dichotomous diagnosis, of which a subset can likely be safely managed nonoperatively.

131 Characterizing atlanto-occipital dissociation and its association with pediatric traumatic cardiac arrest: A descriptive case series

Abstract Primary Subject area Emergency Medicine - Paediatric Background Atlanto-occipital dislocation (AOD) is a type of cervical spine injury (CSI) that is commonly fatal or associated with severe neurologic consequences. Although rare, AOD is now more commonly recognized in children as improved prehospital care allows for more patients to reach trauma centres and undergo definitive imaging. Patients with AOD often present with cardiorespiratory instability and prompt diagnosis is crucial. However, diagnosis may be delayed due to variation in imaging practices and lack of literature on this topic. Objectives Primary objective: Describe the demographic characteristics, clinical presentation, and long-term outcomes of children with AOD, compared to other upper CSI. Secondary objective: Describe the frequency of AOD and other upper CSI in pediatric traumatic cardiac arrest (PTCA) and the utility of a lateral c-spine radiograph in this setting. Design/Methods This was a retrospective, single-centre case series of all pediatric trauma patients age < 16 years diagnosed with upper CSI seen at a tertiary pediatric trauma centre from 2000-2020. Patients were included if they had evidence of bony or ligamentous injury from C0-2. The diagnosis of upper CSI was ascertained on autopsy, when available, then cross-sectional imaging, then plain radiographs, when the other modalities were unavailable. Data was obtained from manual chart review and analyzed using descriptive statistics. Results Thirty-six patients were excluded for not meeting upper CSI criteria. Of 93 patients with upper CSI, 24 had AOD: 14 (15%) complete and 10 (11%) incomplete (Table 1). The mechanism of injury was motor-vehicle-collision in 23 (96%) of these patients, and a fall in one (4%). All patients with complete AOD presented in PTCA and only one (7%) survived. Of seven patients with AOD who received a lateral c-spine x-ray during resuscitation, 5 (71%) had identifiable injuries. In contrast, of the 10 patients with incomplete AOD, only 1 (10%) presented in arrest and none died. Only one patient received an x-ray during resuscitation, which showed the injury but went undetected, and 100% of final diagnoses were made through CT. The majority of incomplete AOD patients were managed non-operatively and had minimal to mild disability. Conclusion In our study population, complete AOD was highly fatal with all patients presenting in PTCA. In contrast, incomplete AOD carried a more favorable prognosis with 100% survival and minimal-mild disability. If there is suspicion for AOD, a lateral c-spine XR in the trauma bay can aid in early diagnosis, guiding neurosurgical management and/or goals of care discussions.

P151. Survival rates in atlanto-occipital dissociation: A look at the past 20 years

<h3>BACKGROUND CONTEXT</h3> Atlanto-occipital dissociation (AOD) has historically been considered a fatal injury. Recent small case series, however, have suggested that AOD injuries have become increasingly survivable. There has not been an adequately powered study that confirms this. <h3>PURPOSE</h3> The aim of this study was to assess whether the survival rate for patients with AOD increased over time. <h3>STUDY DESIGN/SETTING</h3> Retrospective case series. <h3>PATIENT SAMPLE</h3> Patients with traumatic AOD identified from our Level 1 Trauma Center database <h3>OUTCOME MEASURES</h3> Mortality following traumatic AOD. <h3>METHODS</h3> Patients with traumatic AOD from 1996 to 2019 were retrospectively identified from our Level 1 Trauma Center database using International Classification of Diseases 9 and 10 codes. Patients were stratified into two cohorts- those diagnosed before August 1, 2015 and after. <h3>RESULTS</h3> A total of 52 patients met the inclusion criteria with a mean age of 35.3, ISS of 42.8, and admission GCS of 4.5. Thirty-two patients in total died. Mortality rate was 78% pre-2015 and 48% post-2015 respectively (p=.0191). Increased ISS and decreased GCS scores were associated with a significant decrease in survival rate. <h3>CONCLUSIONS</h3> AOD has been implicated as a cause of death in as high as 31% of motor vehicle fatalities. However, our study suggests that clinicians have been more vigilant in early diagnosis and treatment of AOD, as mortality rates have decreased over time. Possible reasons for the improved survival rate seen in this study include: increased awareness of AOD, improved protocols/ more uniform CT based imaging, and advances in the care of these patients. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

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.

Atlanto-occipital dissociation.

Atlanto-occipital dissociation (AOD) is arare and unstable injury of the craniocervical junction, associated with very high morbidity and mortality. The most common cause of this injury is high energy trauma with hyperextension of the cranium, such as car accidents. Due to specific anatomical predispositions, children and young adults are the frequently affected populations. Improving pre-hospital and early emergency care has resulted in ahigher sensitivity of AOD diagnosis. Aretrospective analysis of all patients with cervical spine trauma, treated at the Masaryk Hospital Trauma Center between 2008 and 2018, identified 7 patients with AOD. The cohort consisted of 5 males and 2 females, with amean age of 19,6 years and with the age range 9 to 35 years. All cases occurred as aresult of acar accident. All patients in the cohort had findings of ahighly unstable C0-C1 injury on their CT scans on admission. Four patients died early, while undergoing CPR in the emergency department. Two patients were in severe neurological states, with lesions of the upper cervical spinal cord and medulla oblongata on MRI. These patients were treated with external halo fixation and died within 3 days of the trauma. Only one patient with anew progressive neurological deficit was successfully treated using acute occipitocervical stabilization and fusion. The increasing incidence of AOD requires an early diagnosis, which minimizes the risk of successive clinical deterioration. The diagnostic method of choice is the C1-condyle interval (CCI) CT assessment along with cervical spine MRI. Standard treatment of stable patients with unstable AOD injuries consists in posterior occipitocervical stabilization and fusion of C0-C2.

Tectorial membrane injury in adult and pediatric trauma patients: a retrospective review and proposed classification scheme.

Traumatic tectorial membrane injuries have different radiologic presentations in adult versus pediatric patients. The purpose of this study was to identify and classify the different types of tectorial membrane injuries that occur in the adult and pediatric populations. Patients who suffered tectorial membrane injury were identified retrospectively using the keywords 'tectorial membrane," "craniocervical ligament tear/injury," and "atlanto-occipital dissociation" included in radiology reports between 2012 and 2018 using Nuance mPower software. All relevant imaging studies were reviewed by two certificates of additional qualification-certified neuroradiologists. Detailed descriptions of injuries were recorded along with any relevant additional findings, including clinical history. Ten adults and six pediatric patients were identified with acute traumatic injuries of the tectorial membrane. Ninety percent of the adult patients sustained complete disruptions inferior to the clivus, or subclival, with 22% of tears at the level of the basion and 78% at the level of the odontoid tip. In contrast, 83% of pediatric patients suffered a stripping injury of the tectorial membrane located posterior to the clivus, or retroclival. Stretch injuries of the tectorial membrane were identified in 10% of adults and 17% of pediatric patients. The juvenile-type injury, which causes retroclival epidural hematoma, was determined to preferentially occur in patients less than or equal to 14years of age with a high level of statistical significance (p value = 0.0014). A classification system for tectorial membrane injuries is proposed based on this data: type 1-retroclival stripping injury (more common in pediatric patients); type 2a-subclival disruption at the basion and type 2b-subclival disruption at the odontoid (both more common in adult patients); and type 3-thinning of the tectorial membrane.

Posttraumatic Anatomical Injuries of the Craniovertebral Junction and Treatment Implications: Part II.

This paper is PartII of a two-part report. In PartI of the report, injuries of the occipital bone, atlanto-occipital dissociation and the atlanto-occipital joint space were discussed. This part of the report discusses atlantoaxial dislocation and fractures of the atlas and axis.

Part 2: CBCT EVALUATION OF ATLANTOAXIAL/ATLANTO-OCCIPITAL JOINTS FOR CERVICAL INSTABILITY RISK ASSESSMENT

Background The VAAI1 index measures the vertical relationship of the atlas and axis. Based on prior studies, value less than 0.8 might present a predisposition towards cervical instability. Objective The objective of this study was to determine the potential risk for atlantoaxial/atlanto-occipital instability2 in patients who underwent CBCT imaging of the head at a University-based Maxillofacial Radiology clinic. Material and Methods After an IRB approval, a preliminary study was performed on patients undergoing either pre-implant assessment of jaws or reported for evaluation of atypical facial pain and measurements were recorded. A total of 100 CBCT volumes of patients were identified for the selected craniocervical measurements. It is anticipated that these measurements would provide a risk estimate for cervical instability that could potentially result in spinal cord injury. All CBCT volumes were acquired using Carestream CS9300 machine (Carestream, Atlanta, GA) Results Based on the preliminary results, the average VAAI measurement was 0.7626, the average BAI was 4.970 mm; the average BDI was 5.043 mm and the average PR was 0.6961. Discussion Apart from VAAI, BDI and BAI, the Powers3 ratio was utilized in this study to see atlantoaxial dissociation of subjects (normal Powers ratio= 1:1) A ratio over 1 indicates an Atlanto-Occipital Dissociation (AOD). Basion-axial interval (BAI) is the horizontal distance between basion and the posterior cortex of the axis(normal= Conclusions Based on the preliminary results of this CBCT study, it was clear that the VAAI, BAI, BDI and Powers ratios are all useful markers for early diagnosis of potential atlanto-occipital dissociation injuries. Since the cervical vertebrae are captured on CBCT taken for other purposes, it is an added advantage to be able to assess AOD using these volumes.

Part 1: CBCT EVALUATION OF ATLANTOAXIAL/ATLANTO-OCCIPITAL JOINTS FOR CERVICAL INSTABILITY RISK ASSESSMENT

Background In dental radiography, the vertical atlantoaxial index (VAAI)1 measures the vertical relationship of the atlas and the axis. Based on prior studies, value less than 0.8 might present a predisposition toward cervical instability. The Powers ratio (PR) is the ratio between the distance of 2 lines: (B–P): from basion to posterior arch of C1 (O–A): from opisthion to the anterior arch of atlas. The normal ratio is 1:1, if the ratio exceeds 1, it indicates atlanto-occipital instability. The basion–axial interval (BAI) is the horizontal distance between basion and posterior dens.4 The basion–dens interval (BDI) is the distance between the basion and the tip of the dens.4 Objective The objective of this study was to determine the potential risk for atlantoaxial/atlanto-occipital instability2 in patients who underwent cone beam computed tomography (CBCT) imaging of the head. The research was conducted at the Oral and Maxillofacial Radiology clinic of the University of Pennsylvania School of Dental Medicine (Philadelphia, PA). Materials and Methods After institutional review board approval, a preliminary study was performed on patients undergoing either preimplantation assessment of jaws or evaluation of atypical facial pain, and measurements were recorded. A total of 50 CBCT volumes were identified for the selected craniocervical cephalometric measurements. Analysis of the CBCT volumes and cephalometry were performed to record various craniocervical measurements and determine the potential risk of atlantoaxial atlanto-occipital instability. The measurements were done by using the midsagittal-view CBCT images. These measurements included BAI, BDI, VAAI, and PR. It was anticipated that these measurements would provide a risk estimate for cervical instability that could potentially result in spinal cord injury. All CBCT volumes were acquired by using the Carestream CS9300 machine (Carestream, Atlanta, GA). Results Based on the preliminary results, the average VAAI measurement was 0.7626, the average BAI was 4.970 mm, the average BDI was 5.043 mm, and the average PR was 0.6961. Discussion Apart from VAAI, BDI, and BAI, the PR3 was utilized in this study to find out the atlantoaxial dissociation (normal PR = 1:1). A ratio over 1 indicates atlanto-occipital dissociation (AOD. BAI is the horizontal distance between basion and the posterior cortex of the axis (normal ≤12 mm). BDI is the distance between the basion and the tip of the dens (normal ≤8.5 mm). Both BAI and BDI are used to diagnose AOD injuries.

Independent predictors of survival after traumatic atlanto-occipital dissociation.

Atlanto-occipital dissociation (AOD) occurs when the skull base is forcibly separated from the vertebral column. Existing literature on AOD is sparse and risk factors for mortality are unknown. This study determined independent predictors of survival after AOD. Patients who sustained AOD were identified from the National Trauma Data Bank (2007-2014). Those arriving without signs of life or with missing mortality data were excluded. Study groups were defined as patients who survived to hospital discharge versus patients who died in hospital. Demographics, injury data, interventions, and outcomes were compared between groups using univariate analysis. Multivariate logistic regression was used to determine independent predictors of survival. After applying exclusion criteria, 1,489 patients (<1% of National Trauma Data Bank) were identified. Median age was 37 years (interquartile range [IQR), 20-59 years], and 59% of patients were male. Atlanto-occipital dissociation occurred almost exclusively after blunt mechanisms (97%), most commonly motor vehicle collisions (66%). Median injury severity score (ISS) was 25 (IQR, 10-36), with 22% mortality. Median time to death was 1,358 minutes (IQR, 281-4,451 minutes), approximately 23 hours. Independent predictors of survival were higher Glasgow Coma Scale score on admission (p < 0.001), lower ISS (p = 0.011), lower Abbreviated Injury Scale score for the head (p = 0.001), and the lack of need for exploratory laparotomy (p < 0.001). Time to neurosurgical intervention of the spine was not predictive of survival (p > 0.05). Patients who survived had a median hospital length of stay of 5 days (IQR, 1-14 days) and intensive care unit length of stay of 1 day (IQR, 0-7 days). The most common discharge destination was home (n = 393 [34%]). Traumatic AOD is not uniformly fatal, with 78% of patients who arrive alive to hospital surviving to discharge. When death occurs, it is typically within the first 23 hours. Lower ISS and higher Glasgow Coma Scale score on admission independently predict survival, while time to neurosurgical intervention does not. Survivors have a short hospital stay and are commonly discharged home. This study suggests that AOD among patients who arrive alive to hospital may not be as devastating as previously considered. Progonostic/Epidemiological, level III; Therapeutic, level IV.

Traumatic atlanto-occipital dissociation: No longer a death sentence

BackgroundTraumatic atlanto-occipital dissociation is considered highly unstable and was once believed to be uniformly fatal. With recent advances in prehospital care, coupled with early diagnosis and stabilization, these injuries are potentially survivable. The aim of this study was to identify potentially modifiable risk factors associated with improved outcomes after a traumatic atlanto-occipital dissociation. MethodsPatients with traumatic atlanto-occipital dissociation over a 17-year period were identified and stratified by age, sex, injury severity, and severity of shock. Time to diagnosis, time to and method of stabilization, and mortality were compared. Multivariable logistic regression was performed to determine which factors were independent predictors of mortality. ResultsFifty-two patients were identified with a mean age of 44, an admission Glasgow Coma Score of 8, and an Injury Severity Score of 34; of these 52 patients, 38 (73%) underwent stabilization. Overall mortality was 33%. Of the survivors, 34 patients (97%) were discharged neurologically intact. One patient was discharged with neurologic deficits. Multivariable logistic regression identified admission Glasgow Coma Score (odds ratio 0.7; 95% confidence interval 0.552–0.877) as the only independent predictor of death after traumatic atlanto-occipital dissociation. ConclusionTraumatic atlanto-occipital dissociation remains a rare injury following blunt trauma. Clinical presentation is a predictor of mortality. Prompt diagnosis is crucial in promoting rapid stabilization and improving survivability. Survival to hospital discharge portends improved functional outcome.

Diagnosis of atlanto-occipital dissociation: Standardised measurements of normal craniocervical relationship in finless porpoises (genus Neophocaena) using postmortem computed tomography

Due to the different craniocervical structures in humans and cetaceans, a standardised method assessing the normal craniocervical relationship in cetaceans is lacking, causing difficulties in defining the presence of atlanto-occipital dissociation (AOD) in cetaceans. The present study aimed to 1) describe a novel standardised method of determining the normal craniocervical relationships, and 2) define the 95% accuracy range of the normal craniocervical relationship in finless porpoises (genus Neophocaena), that allowed AOD diagnosis. Fifty-five out 83 stranded or by-caught finless porpoise carcasses were analyzed in term of their craniocervical relationship in dorsal-ventral and medial-lateral dimension, using postmortem computed tomography measurements. The normal craniocervical relationship in both dorsal-ventral (mean BD/OV: 0.87 ± 0.24 [2 SD]) and medial-lateral dimension (mean VR/VL: 0.98 ± 0.17 [2 SD]) was first defined. The 95% accuracy ranges of the normal craniocervical relationship in dorsal-ventral (0.63–1.11) and medial-lateral dimension (0.82–1.15) were proposed. The baseline ranges could facilitate AOD assessment, and provide an objective means of record for AOD related injury and death of cetaceans caused by anthropogenic trauma. The technique developed may be applied to live cetaceans with abnormal craniocervical relationship to aid diagnosis and guide corrective therapy.

Anomaly-Related Pathologic Atlantoaxial Displacement in Pediatric Patients.

To analyze clinical and radiologic features of pathologic atlantoaxial displacement (PAAD) in pediatric patients and to compose a treatment algorithm for anomaly-related PAAD. Criteria of different types of PAAD and treatment algorithms have been widely reported in the literature but are difficult to apply to patients with odontoid abnormalities, C2-C3 block, spina bifida C1, and children. We evaluated results of treatment of 29 pediatric patients with PAAD caused by congenital anomalies of the craniovertebral junction (CVJ), treated in Ilizarov Center in 2009-2017, including 20 patients with atlantoaxial displacement (AAD) and 9 patients with atlantoaxial rotatory fixation. There were 14 males (48.3%) and 15 females (51.7%). We singled out 3 groups of patients: nonsyndromic (6 patients, 20.7%), Klippel-Feil syndrome (13 patients, 44.8%), and syndromic (10 patients, 34.5%). Odontoid abnormalities and C1 dysplasia were widely represented in the syndromic group. Local symptoms predominated in the nonsyndromic and KFS groups. In the syndromic group, all patients had AAD and myelopathy. A pronounced decrease of space available for chord C1 and increase of anterior atlantodental interval were noted compared with other groups. We present a unified treatment algorithm of pediatric anomaly-related PAAD. Syndromic AAD are often accompanied by anterior and central dislocation and myelopathy and atlantooccipital dissociation. These patients require early aggressive surgical treatment. Nonsyndromic and Klippel-Feil syndrome AAD, atlantoaxial subluxation, and atlantoaxial fixation often manifest by local symptoms and need to eliminate CVJ instability. Existing classifications of symptomatic atlantoaxial displacement are not always suitable for patients with CVJ abnormalities.

Ability of magnetic resonance imaging to accurately determine alar ligament integrity in patients with atlanto-occipital injuries.

Objective:The objective of this study is to evaluate the the reliability of magnetic resonance imaging (MRI) in diagnosing alar ligament disruption in patients with potential atlanto-occipital dissociation (AOD).Materials and Methods:Three-blinded readers performed retrospective review on 6 patients with intra-operative confirmed atlanto-occipital dissocation in addition to a comparison cohort of patients with other cervical injuries that did not involve the atlanto-occipital articulation. Ligament integrity was graded from 1 to 3 as described by Krakenes et al. The right and left ligaments were assessed separately. Inter-observer agreement by patient, by group (AOD vs. non-AOD), and intra-observer agreement was calculated using weighted Cohen's kappa.Results:Interobserver agreement of alar ligament grade for individual patients ranged from slight to fair (κ = 0.05–0.30). Interobserver agreement of alar ligament grade for each group (AOD vs. non-AOD) ranged from fair to substantial (κ = 0.37–0.66). No statistically significant difference in categorical analysis of groups (AOD vs. non-AOD) and grade (0–1 vs. 2–3) was observed. Intraobserver agreement of individual patient's alar ligament grade ranged from moderate to substantial (κ = 0.50–0.62).Conclusion:The use of MRI to detect upper cervical ligament injuries in AOD is imperfect. Our results show inconsistent and unsatisfactory interobserver and intraobserver reliability in evaluation of alar ligament injuries. While MRI has immense potential for detection of ligamentous injury at the craniovertebral junction, standardized algorithms for its use and interpretation need to be developed.

Cervical spine injuries in young children: pattern and outcomes in accidental versus inflicted trauma

BackgroundThe aim of the study was to compare the cervical spine (c-spine) pattern of injury and outcomes in children below 3 y with a head injury from confirmed inflicted versus accidental trauma. MethodsAfter Institutional Review Board approval, data were prospectively collected between July 2011 and January 2016. Inclusion criteria were age below 3 y, a loss of consciousness, and any one of the following initial head computed tomography (CT) findings (subdural hematoma, intraventricular, intraparenchymal, subarachnoid hemorrhage, or cerebral edema). A protocol of brain and neck magnetic resonance imaging and magnetic resonance angiography was instituted. Brain and neck imaging results, clinical variables, and outcomes were recorded. Data were compared by t-test for continuous and Fisher exact test for categorical variables. Results73 children were identified, 52 (71%) with inflicted and 21 (29%) with accidental trauma. The median age was 11 mo; (range: 1-35 mo). Ten (14%) had c-spine injuries, 7/52 (13%) inflicted, and 3/21 (14%) accidental. The mechanism was shaking for all inflicted and motor vehicle accident or pedestrian struck for accidental c-spine injuries. The inflicted group were significantly younger (P = 0.03), had higher Injury Severity Scores (P = 0.02), subdural hematomas (P = 0.03), fractures (P = 0.03), retinal hemorrhages (P = 0.02), brain infarcts (P = 0.01), and required cardiopulmonary resuscitation (P = 0.01). Seven with inflicted trauma died from brain injury (9.5%), one had atlanto-occipital dissociation. Six mortalities (86%) had no c-spine injury. Six with inflicted c-spine injuries survived with neurologic impairment, whereas three with accidental survived without disability, including one atlanto-occipital dissociation. ConclusionsCompared to accidental trauma, young children with inflicted c-spine injuries have more multisystem trauma, long-term disability from brain injury, and an injury pattern consistent with shaking.

Cervical spine imaging for young children with inflicted trauma: Expanding the injury pattern

AimThe purpose of this study was to document the incidence and pattern of cervical spine (c-spine) injuries in children below 36months with inflicted trauma. MethodsAn IRB approved, prospective cohort study was performed between July 2011 and January 2016. Inclusion criteria were: age below 36months, loss of consciousness after inflicted trauma, and one initial head computed tomography finding: a subdural, intraventricular, intraparenchymal, subarachnoid hemorrhage, diffuse axonal injury, hypoxic injury, or cerebral edema. A protocol of brain and neck magnetic resonance imaging and angiography was obtained within 48h. Variables were compared by t-test and Fisher-exact test. ResultsThere were 53 children (median age: five months; range: 1–35months), 38 males (71.7%), of which seven died (13.2%). C-spine injury was identified in 8 (15.1%): ligamentous injury (2), vertebral artery shear injury (1), atlantooccipital dissociation (AOD) (1), cord injury with cord epidural hematoma (2), and isolated cord epidural hematoma (2). Retinal hemorrhages (p=0.02), shaking (p=0.04), lower Glasgow coma score (GCS) (p=0.01), brain infarcts (p=0.01), and hypoxic/ischemic injury (p=0.01) were associated with c-spine injury. One with AOD died. Six had significant disability. ConclusionFor small children with inflicted trauma, the c-spine injury incidence is 15.1%. The injury pattern includes retinal hemorrhages, shaking, lower GCS, and brain injury. Evaluation of shaken infants should include c-spine imaging. Level of evidenceLevel 2 A- This is a prospective cohort study with complete follow-up to hospital discharge or death. In all cases, inflicted trauma was confirmed. Owing to the nature of child abuse, the precise time of injury is not known. All children underwent a strict imaging protocol on arrival to hospital that was supervised on a prospective basis.

Outcome of conservatively treated occipital condylar fractures - A retrospective study.

Introduction:Occipital condyle fracture (OCF) is rare. It may, however, pose a serious threat to the patient due to destabilization of the craniocervical junction. Correct diagnosis and effective treatment are essential to prevent long-term complications. The aim of this study was to retrospectively investigate our current treatment program with focus on the functional outcome. Diagnosis and classification systems were evaluated for their usefulness in the clinical practice.Materials and Methods:We retrospectively reviewed all patients treated conservatively for an occipital condylar fracture from 2010 to 2015 at our department. Fracture classifications were performed according to three established systems. The patients were followed up with clinical examination and plain radiographs at weeks 2, 6, and 12 with the addition of a dynamic flexion-extension X-ray at week 14.Results:Totally 24 patients met the inclusion criteria. One was lost to follow-up and two ended treatment before completing the full treatment program due to a clinical decision. Fracture displacement was neither detected nor was any neurological deficits observed. Most patients were pain free after 6 weeks. After 14 weeks’ treatment, two patients still had neck pain; the rest were pain free.Conclusions:Our data suggest that twelve weeks’ conservative treatment is not necessary for unilateral OCFs without atlanto-occipital dissociation (AOD). We recommend 6 weeks of conservative treatment, with clinical control and flexion-extension radiographs before ending treatment. Plain radiography is of limited value in the clinical control of this fracture type. Anderson and Montesano and Tuli et al. classification systems fulfill an academic role. We found the classification system by Mueller et al. to be more helpful in everyday clinical practice.

Post-mortem CT evaluation of atlanto-occipital dissociation

Atlanto-occipital dissociation injury is an important injury in forensic pathology practice. Radiological diagnosis of atlanto-occipital dissociation clinically is assessed by direct measurement of occipito-vertebral skeletal relationships. Different measurements may be used to diagnose atlanto-occipital dissociation, including the basion-dens interval (BDI) and basion-axial interval (BAI). It is not known whether the normal ante-mortem measurements of BDI and BAI described in the literature are applicable to post-mortem CT images of the occipito-cervical junction (OCJ) or whether these measurements could be affected by early post-mortem changes. This study aims to compare post-mortem BDI and BAI measurements with ante-mortem values. Post-mortem CT scans of the cervical spines of 100 deceased adults were reviewed, and the BDI and BAI were measured. Different parameters were recorded in each case. The results from this study suggest that there are no effects of post-mortem changes on the measurement of BAI as relied upon clinically. There appear to be some effects of fully established rigor mortis on BDI measurement, shortening it. This may have consequences for the post mortem diagnosis of atlanto-occipital dissociation.