AOSpine Thoracolumbar Spine Injury Classification Research Articles

Neurosurgery compared to orthopedic spine consultation: A single level I trauma center experience

IntroductionBoth Orthopedic Surgery (OS) and Neurosurgery (NS) perform spine surgery in the setting of trauma. However, it is unknown whether outcomes differ between these specialties. This study compares management and outcomes for vertebral fractures between NS and OS, hypothesizing similar operation rate, length of stay (LOS), and readmission. Research questionDo outcomes differ between NS and OS in the management of vertebral fractures following trauma? MethodsA retrospective single-center study was conducted on adult patients with cervical, thoracic, lumbar, and sacral fractures treated at a single trauma center, where no standardized pathway exists across NS and OS. Patients were compared for injury profile, diagnostic imaging, and operative techniques as well as LOS, mortality, and complications. ResultsA total of 630 vertebral fracture patients (OS:350 (55.6%); NS:280 (44.4%)) were included. NS utilized magnetic resonance imaging (MRI) more commonly (36.4% vs. 22.6%, p < 0.001). NS patients more often underwent operation (13.2% vs. 7.4%, p = 0.016) despite similar fracture number and severity (p > 0.05). Post-operative complications, LOS, and readmission rates were similar between cohorts (p > 0.05). Discussion and conclusionDespite similar injury profiles, NS had higher rates of MRI usage and operative interventions in the context of traumatic spine fractures. Despite differences in management, major clinical outcomes were similar between NS and OS. However, we do call for further standardization of evaluation and treatment of patients based on established algorithms from such as the AOSpine Thoracolumbar Spine Injury Classification System (ATLICS).

Automated detection and classification of acute vertebral body fractures using a convolutional neural network on computed tomography.

Acute vertebral fracture is usually caused by low-energy injury with osteoporosis and high-energy trauma. The AOSpine thoracolumbar spine injury classification system (AO classification) plays an important role in the diagnosis and treatment of the disease. The diagnosis and description of vertebral fractures according to the classification scheme requires a great deal of time and energy for radiologists. To design and validate a multistage deep learning system (multistage AO system) for the automatic detection, localization and classification of acute thoracolumbar vertebral body fractures according to AO classification on computed tomography. The CT images of 1,217 patients who came to our hospital from January 2015 to December 2019 were collected retrospectively. The fractures were marked and classified by 2 junior radiology residents according to the type A standard in the AO classification. Marked fracture sites included the upper endplate, lower endplate and posterior wall. When there were inconsistent opinions on classification labels, the final result was determined by a director radiologist. We integrated different networks into different stages of the overall framework. U-net and a graph convolutional neural network (U-GCN) are used to realize the location and classification of the thoracolumbar spine. Next, a classification network is used to detect whether the thoracolumbar spine has a fracture. In the third stage, we detect fractures in different parts of the thoracolumbar spine by using a multibranch output network and finally obtain the AO types. The mean age of the patients was 61.87 years with a standard deviation of 17.04 years, consisting of 760 female patients and 457 male patients. On vertebrae level, sensitivity for fracture detection was 95.23% in test dataset, with an accuracy of 97.93% and a specificity of 98.35%. For the classification of vertebral body fractures, the balanced accuracy was 79.56%, with an AUC of 0.904 for type A1, 0.945 for type A2, 0.878 for type A3 and 0.942 for type A4. The multistage AO system can automatically detect and classify acute vertebral body fractures in the thoracolumbar spine on CT images according to AO classification with high accuracy.

Reliability and Reproducibility Analysis of the AOSpine Thoracolumbar Spine Injury Classification System in Korea

Reliability and Reproducibility Analysis of the AOSpine Thoracolumbar Spine Injury Classification System in Korea

Концепция лечения взрывных переломов и переломов тел позвонков с дистракцией и ротацией грудного и поясничного отделов позвоночника по принципу остаточной фиксированности

Актуальность. Для решения задачи создания концепции и алгоритма лечения прежде всего необходимо разработать рабочую классификацию, на основе которой будет построена концепция. Предложенная классификация должна обеспечить выбор наиболее эффективных методов лечения у каждого больного, одновременно максимально безопасных и малотравматичных. Классификационное распределение основано на диагностических признаках переломов тел позвонков, а именно определении морфологических факторов, приводящих к патологическим изменениям. Именно выявление характера и тяжести повреждения позвоночного сегмента позволяет предвидеть дальнейшее развитие деформации и оценивать эффективность использования определенного метода лечения в конкретной клинической ситуации. Материалы и методы. Общее число больных с травматическими повреждениями грудного и поясничного отделов позвоночника составило 113. Средний возраст пациентов — 34,3 года. Мужчин было 67,9 %, женщин — 32,1 %. Проведено ретроспективное исследование историй болезни, данных клинического обследования, рентгенологических, КТ, МРТ до и после лечения. Критерии включения: неосложненные и осложненные взрывные переломы и переломы тел позвонков с дистракцией и ротацией грудного и поясничного отделов позвоночника. Согласно универсальной классификации повреждений грудного и поясничного отделов позвоночника Magerl et al., которая является классификацией AOSpine Thoracolumbar Spine Injury Classification System, различают: неполный взрывной перелом типа А 3.1 и неполный взрывной перелом с раскалыванием типа А 3.2, полный взрывной перелом типа А 3.3, перелом тела позвонка типа А с дистракцией типа АВ (тип В 1.2, В 2.3) и перелом тела позвонка типа А с ротацией типа АС (тип С 1.3). В зависимости от наличия неврологической симптоматики пациентов распределили на тех, кто имел несложные (74 человека; 65,4 %) и осложненные (39; 34,5 %) повреждения. Результаты. Разработка классификации предполагает анализ диагностических критериев, а разработка концепции лечения — анализ эффективности определенного метода лечения. Предложенная рабочая хирургическая классификация создана на основе классификаций Magerl et al., TLIСS и распределения внутренних напряжений McCormack, а также результатов собственных экспериментальных и клинических исследований. В результате собственных клинико­экспериментальных исследований доказано, что с увеличением степени разрушения тела позвонка растет величина кифотической деформации на уровне повреждения. Таким образом, величина первичной кифотической деформации позвоночника напрямую зависит от степени разрушения тела позвонка (степень фрагментации). Выводы. Разработана концепция лечения пациентов с взрывными переломами и переломами тел позвонков с дистракцией и ротацией, которая позволяет выбрать оптимальный метод лечения на основании трех признаков: степени фрагментации тела позвонка, деформирования позвоночника по принципу остаточной фиксированности и деформирования позвоночного канала.

The reliability of the AOSpine Thoracolumbar Spine Injury Classification System in children: an international validation study.

PurposeTo evaluate the AOSpine Thoracolumbar Spine Injury Classification System and if it is reliable and reproducible when applied to the paediatric population globally.MethodsA total of 12 paediatric orthopaedic surgeons were asked to review MRI and CT imaging of 25 paediatric patients with thoracolumbar spine traumatic injuries, in order to determine the classification of the lesions observed. The evaluators classified injuries into primary categories: A, B and C. Interobserver reliability was assessed for the initial reading by Fleiss’s kappa coefficient (kF) along with 95% confidence intervals (CI). For A and B type injuries, sub-classification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff’s alpha (αk) along with bootstrapped 95% CIs. A second round of classification was performed one-month later. Intraobserver reproducibility was assessed for the primary classifications using Fleiss’s kappa and sub-classification reproducibility was assessed by Krippendorff’s alpha (αk) along with 95% CIs.ResultsIn total, 25 cases were read for a total of 300 initial and 300 repeated evaluations. Adjusted interobserver reliability was almost perfect (kF = 0.74; 95% CI 0.71 to 0.78) across all observers. Sub-classification reliability was substantial (αk= 0.67; 95% CI 0.51 to 0.81), Adjusted intraobserver reproducibility was almost perfect (kF = 0.91; 95% CI 0.83 to 0.99) for both primary classifications and for sub-classifications (αk = 0.88; 95% CI 0.83 to 0.93).ConclusionThe inter- and intraobserver reliability for the AOSpine Thoracolumbar Spine Injury Classification System was high amongst paediatric orthopaedic surgeons. The AOSpine Thoracolumbar Spine Injury Classification System is a promising option as a uniform fracture classification in children.Level of EvidenceIII

Superiority of thoracolumbar injury classification and severity score (TLICS) over AOSpine thoracolumbar spine injury classification for the surgical management decision of traumatic spine injury in the pediatric population.

Thoracolumbar fractures are the most common kind of spine injury in children. Several types of spine injury can occur, and for this reason, treatment algorithms have been put in place for the management of these patients. At present, the thoracolumbar injury classification and severity score system (TLICS) and the thoracolumbar AOSpine injury score (AOSpine score) aimed at providing treatment recommendations. We aimed to assess the reliability, in children, of the TLICS scoring and AOSpine scoring systems, and to define the superiority of one of the methods of scoring, to spread its use in routine clinical management in the pediatric spine trauma. A retrospective chart review of consecutive children admitted to a Level 1 trauma center for traumatic thoracolumbar fractures, between 2006 and 2019, was performed. We compared the management we performed in clinical practice in children with spine trauma, to the decisional algorithms based on the TLICS and AOSpine scores. According to these scores, surgical treatment should be performed when the TLICS score ≥ 5 and the AOSpine score > 5; and surgical or conservative treatment was considered reasonable when the TLICS score = 4 and the AOSpine score = 4 or 5. Surgical indications were based on the clinical status, the anatomy of the fracture, and the risk of sagittal imbalance of the growing spine. Fifty-four patients met the inclusion criteria. We demonstrated that both the AOSpine score and the TLICS scores had a significant correlation for surgical management decision of spine trauma (p < 0.0001). We found a high concordance between surgical decision making in the pediatric clinical practice and the TLICS score. In our pediatric cohort, there were significantly more patients with TLICS ≥ 5 (n = 47, 87%) than with AOSpine score > 5 (n = 26, 46%, p < 0.0001). There were significantly more patients with TLICS ≥ 4 (n = 53, 98%), than with AOSpine score ≥ 4 (n = 42, 77%, p = 0.001). ConclusionsThe TLICS score was significantly more appropriate than the AOSpine score, for the surgical treatment decision in children, especially when considering the future risk of sagittal imbalance.

Burst fractures lead to a fracture-associated intervertebral vacuum phenomenon: a case series of 305 traumatic fractures of the thoracolumbar spine

Intervertebral vacuum phenomenon (IVP) is mainly seen as a sign of degenerative disc diseases. Although studies have shown that IVP also occurs after traumatic injuries to the spine, its clinical relevance in spinal fractures remains unknown. Therefore, the aim of this study was to analyse the prevalence, demographic parameters and fracture morphology in patients with fracture-associated IVP (FAVP) of the thoracolumbar spine. In this retrospective cohort study, patients with traumatic fractures of the thoracolumbar spine who were admitted between January 2014 and December 2015 were included. CT scans were assessed for the presence of intervertebral areas of gaseous radiolucency, which were defined as IVP. Fractures were classified according to the AOSpine Thoracolumbar Spine Injury Classification System. Demographic and anamnestic data, including age, sex and trauma mechanism, were documented. A total of 201 patients with 305 fractures were included. Seventy-three patients with 98 fractures had follow-up CTs. Sixty-eight patients had IVP, of whom 46 patients had FAVP. On the follow-up CT, a significant correlation was found between A3 fractures and FAVP, while initial FAVP was significantly correlated with age and low-velocity trauma mechanisms. Initial degenerative IVP also showed a significant correlation with age. FAVP occurred significantly more often in burst fractures and therefore may lead to disc degeneration due to nutritional supply disturbances via the vertebral endplate. As surgical management strategies for burst fractures are intensively discussed, the appearance of FAVP should be taken in consideration.

The Reliability of the AOSpine Thoracolumbar Classification System in Children: Results of a Multicenter Study.

The purpose of this study was to determine whether the new AOSpine thoracolumbar spine injury classification system is reliable and reproducible when applied to the pediatric population. Nine POSNA (Pediatric Orthopaedic Society of North America) member surgeons were sent educational videos and schematic papers describing the AOSpine thoracolumbar spine injury classification system. The material also contained magnetic resonance imaging and computed tomography imaging of 25 pediatric patients with thoracolumbar spine injuries organized into cases to review and classify. The evaluators classified injuries into 3 primary categories: A, B, and C. Interobserver reliability was assessed for the initial reading by Fleiss kappa coefficient (kF) along with 95% confidence interval (CI). For A and B type injuries, subclassification was conducted including A0 to A4 and B1 to B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff alpha (αk) along with bootstrapped 95% CI. Imaging was reviewed a second time by all evaluators ~1 month later. All imaging was blinded and randomized. Intraobserver reproducibility was assessed for the primary classifications using Fleiss kappa and subclassification reproducibility was assessed by Krippendorff alpha (αk) along with 95% CI. Interpretations for reliability estimates were based on Landis and Koch (1977): 0 to 0.2, slight; 0.2 to 0.4, fair; 0.4 to 0.6, moderate; 0.6 to 0.8, substantial; and >0.8, almost perfect agreement. Twenty-five cases were read for a total of 225 initial and 225 repeated evaluations. Adjusted interobserver reliability was almost perfect (kF=0.82; CI, 0.77-0.87) across all raters. Subclassification reliability was substantial (αK=0.79; CI, 0.62-0.90). Adjusted intraobserver reproducibility was almost perfect (kF=0.81; CI, 0.71-0.90) for both primary classifications and for subclassifications (αk=0.81; CI, 0.73-0.86). The reliability for the AOSpine thoracolumbar spine injury slassification System was high amongst POSNA surgeons when applied to pediatric patients. Given a lack of a uniform classification in the pediatric population, the AOSpine thoracolumbar spine injury classification system has the potential to be used as the first universal spine fracture classification in children. Level III.

Operative versus Non-Operative Management of Traumatic Thoracolumbar Injuries according to the AO Spine Thoracolumbar Spine Injury Classification System

AbstractIntroduction The AOSpine Thoracolumbar Spine Injury Classification (AOSTSIC) system has been proposed to better characterize injury morphologies and improve the classification of thoracolumbar (TL) spine trauma. However, the indications for surgical treatment according to the AOSTSIC system are still debated. Additionally, the proposed Thoracolumbar AOSpine Injury Score (AOSIS) is quite complex, which may preclude its use in daily practice. The objective of this review is to discuss the AOSTSIC system and its indications for initial nonoperative versus surgical management of acute TL spine trauma.Methods We analyzed the literature for each injury type (and subtype, when pertinent) according to the AOSTSIC system as well as their potential treatment options.Results Patients with AOSTSIC subtypes A0, A1, and A2 are neurologically intact in the vast majority of the cases and initially managed nonoperatively. The treatment of A3- and A4-subtype injuries (burst fractures) in neurologically-intact patients is still debated with great controversy, with initially nonoperative management being considered an option in select patients. Surgery is recommended when there are neurological deficits or failure of nonoperative management, with the role of magnetic resonance findings in the Posterior Ligamentous Complex (PLC) evaluation still being considered controversial. Injuries classified as type B1 in neurologically-intact patients may be treated, initially, with nonoperative management, provided that there are no ligamentous injury and non-displacing fragments. Due to severe ligamentous injury, type-B and type-C injuries should be considered as unstable injuries that must be surgically treated, regardless of the neurological status of the patient.Conclusions Until further evidence, we provided an easy algorithm-based guide on the spinal trauma literature to help surgeons in the decision-making process for the treatment of TL spine injuries classified according to the new AOSTSIC system.

Determination of Any Correlation between Sagittal Spinopelvic Configuration and Progressive Collapse of Acute Osteoporotic Compression Spine Fractures: A Retrospective Radiological Analysis.

Study DesignA retrospective cohort study.PurposeThe aim of this study was to determine any correlations between spinopelvic configuration and progressive collapse following acute osteoporotic compression spine fractures.Overview of LiteratureFew studies have investigated the risk factors for progressive osteoporotic compression spine fractures. However, the correlation between the spinopelvic configuration, which is a crucial to optimize the management of lumbar degenerative diseases, and progressive collapse following acute osteoporotic compression spine fractures was not analyzed.MethodsWe retrospectively identified all patients treated for thoracolumbar fractures in Assaf Harofe Medical Center between January 2008 and July 2013. Pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT) were measured for the pelvic parameters. For each patient, we classified the fracture according to the AOSpine Thoracolumbar Spine Injury Classification System. Height loss was measured initially and at a minimum of 3-month follow-up. The difference between initial and final height loss was documented as height loss difference.ResultsThe study included 124 patients comprised 86 women and 38 men. The mean patient age was 69±9.6 years. The mean length of follow-up was 14±15 months. No significant effect of the PI, PT, and SS angles on the vertebral fracture level (p>0.05) was found. Similarly, no significant relationship between the PI, PT, and SS angle and the fracture type according to the AO classification (p>0.05) was found. There was no correlation between PI, PT, and SS angles and initial height loss, final height loss and height loss difference (p>0.05)ConclusionsThe spinopelvic configuration represented by the PI, PT, and SS angle does not influence progressive collapse following acute osteoporotic compression spine fractures.

The AOSpine thoracolumbar spine injury classification system: A comparative study with the thoracolumbar injury classification system and severity score in children.

Background:There is no uniform classification in the pediatric population for thoracolumbar (TL) fractures, nor any operative guidelines. This study evaluates the AOSpine TL spine injury classification in the pediatric population and compares it to the thoracolumbar injury classification system (TLICS), which has previously been validated in pediatric spine trauma.Methods:Twenty-eight patients with operative TL injuries were identified from 2006 to 2016. Inclusion criteria included available imaging, operative records, age <18, and posterior approach. Each case was classified by AOSpine TL spine injury classification and TLICS. Each classification was compared to documented intraoperative posterior ligamentous complex (PLC) integrity as well as each other.Results:Utilizing the AOSpine TL spine injury classification, 7 patients had type A injuries, 15 patients had type B injuries, and 6 patients had type C injuries; 21 patients had injuries classified as involving the PLC. Using TLICS, 16 patients had burst fractures, 6 patients had distraction injuries, and 6 patients had translation injuries; 21 patients had injuries classified as involving the PLC. Spearman correlation analysis substantiated convergence of AOSpine TL spine injury classification scores to TLICS scores (r = 0.75; 95% confidence interval, CI = 0.51 to 0.98; P < .001). Concordance between PLC integrity by each classification and intraoperative evaluation was 96% (27/28) of cases (k = 0.91; 95% CI = 0.73 to 1.08). Neurologic status was 100% concordant between the AOSpine TL spine injury classification and TLICS.Conclusion:There is high statistical correlation between the AOSpine TL spine injury classification and TLICS, and to intraoperative evaluation of the PLC, suggesting that the AOSpine TL spine injury classification is applicable to the pediatric population.Level of evidence:III.

164. The reliability of the AOSpine thoracolumbar spine injury classification system in children: results of a multicenter study

BACKGROUND CONTEXT In the adult population, there have been significant endeavors in developing classification systems of thoracolumbar injuries. These systems evolved from simple morphologic classifications to more complex systems based on fracture morphology (injury mechanism), evaluation of posterior ligamentous integrity, and neurologic status of the patient. There does not yet exist a dedicated classification system for pediatric thoracolumbar fractures despite the discordance in presentation. Pediatric thoracolumbar fractures vary in morphology, severity, and morbidity. Treatments vary from observation to surgery depending on factors such as fracture stability, displacement, and neurologic status. PURPOSE The purpose of this study was to determine if the new AOSpine thoracolumbar spine injury classification system is reliable and reproducible when applied to the pediatric population. STUDY DESIGN/SETTING Multicenter review of single institutional case series. PATIENT SAMPLE Patients under the age of 18 years who had been treated operatively for a thoracolumbar fracture between 2006 and 2016 were identified. Inclusion criteria included patients with preinjury computed tomography (CT) scans and magnetic resonance imaging (MRI) and who were less than 18 years of age. OUTCOME MEASURES Classification through AOSpine Thoracolumbar Spine Injury Classification System METHODS A group of nine POSNA (Pediatric Orthopaedic Society of North America) member surgeons were sent an electronic link containing educational videos and schematic papers describing the AOSpine Thoracolumbar Spine Injury Classification System. The link also contained MRI (magnetic resonance imaging) and CT (computed tomography) imaging of 25 pediatric patients with thoracolumbar spine injuries organized into cases to review and classify. The evaluators classified injuries into 3 primary categories: A, B, and C. Interobserver reliability was assessed for the initial reading across all 9 raters by Fleiss's kappa coefficient (kF) along with 95% confidence intervals (CI). For A and B type injuries, subclassification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff's alpha (αk) along with bootstrapped 95% CIs. Imaging was reviewed a second time by all 9 evaluators approximately one month from the initial read. All patient imaging was blinded and randomized for each read independently. Intraobserver reproducibility was assessed for the primary classifications using Fleiss's kappa and subclassification reproducibility was assessed by Krippendorff's alpha (αk) along with 95% CIs. Interpretations for reliability estimates were based on Landis and Koch (1977): 0-0.2, slight; 0.2-0.4, fair; 0.4-0.6, moderate; 0.6-0.8, substantial; and >0.8, almost perfect agreement. RESULTS Twenty-five cases were read by 9 raters for a total of 225 initial and 225 repeated evaluations. Interobserver reliability was almost perfect (kF = 0.82; CI = 0.77 - 0.87) across all 9 raters. Subclassification reliability was substantial (αK = 0.79; CI = 0.62 - 0.90). Intraobserver reproducibility was almost perfect (kF= 0.81; CI = 0.71 - 0.90) for both primary classifications and for subclassifications (αk = 0.81; CI = 0.73 - 0.86). CONCLUSIONS The reliability for the AOSpine classification system was high amongst POSNA surgeons when applied to pediatric patients. Given a lack of a uniform classification in the pediatric population, the AOSpine Thoracolumbar Spine Injury Classification System has the potential to be used as the first universal spine fracture classification in children. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Reliability and Agreement of Different Spine Fracture Classification Systems: An Independent Intraobserver and Interobserver Study

Currently, no spinal classification system has achieved universal acceptance. Therefore, it is important to choose a reliable classification within clinical practice. The objective of this study was to determine and compare the intraobserver and interobserver agreement of the Load Sharing Classification (LSC), the Thoracolumbar Injury Classification System (TLICS), and the AOSpine Thoracolumbar Spine Injury Classification System. In this web-based intraobserver and interobserver study (www.spine.hostei.com), plain radiographs and computed tomographic scans of traumatic thoracolumbar fractures (T12-L2) were evaluated. By use of a questionnaire, fractures were classified according to the LSC, the TLICS, and the AOSpine classification. Data were analyzed with SPSS (Version 21, 76 Chicago, Illinois, USA). Intraobserver and interobserver agreement was determined by the Cohen κ. Statistical significance was defined as P < 0.05. Data from 91 patients were classified twice by 7 board-certified spine surgeons. The intraobserver and interobserver reliability considering the LSC total score was noted as fair (intraobserver/interobserver reliability: κ= 0.26/0.22). Considering the resulting TLICS total score, a moderate intraobserver agreement (κ= 0.41) was noted, whereas the interobserver results presented only fair reliability (κ= 0.23). In contrast to the LSC and the TLICS, the AOSpine classification showed substantial agreement considering the fracture type (A;B;C) (intraobserver/interobserver reliability: κ= 0.71/0.61) and moderate agreement considering the fracture subtype (e.g., A0;A1;…;B1;…) (intraobserver/interobserver reliability: κ= 0.57/0.48). In conclusion, the reliability of the AOSpine fracture classification is superior to the TLICS and the LSC. Therefore, this classification system could best be applied within clinical practice.

Thoracolumbar fractures classification using the smartphone

A recent clinical study found that diagnosing and classifying thoracolumbar fractures using a portable smartphone is as reliable as using a workstation-based picture archiving communication system (PACS) (1). This reliability is comparable to studies of reliability based on the use of PACS work-stations only (2). Substantial agreement for the AO and the Denis classifications was found. The AOspine thoracolumbar spine Injury classification system (AO-TLICS) strongly influences management, with fractures scoring more than five points considered surgical candidates (3); fractures classified as B2 fractures would score 6 points, B3 score 7 points, and C score 8 points ( Figure 1 ). Unsurprisingly, a statistical correlation is seen between the agreement of fracture management and the grading of fracture severity using the AO-TLICS quantification score.

Reliability of the AOSpine thoracolumbar spine injury classification system and thoracolumbar injury classification and severity score (TLICS)

Several classification schemes have been proposed for thoracolumbar spinal injuries over the years, with the goal of facilitating communication and streamlining selection of optimal treatment strategies. None of these have achieved universal acceptance. An ideal classification system is expected to categorize injuries in a way that permits identification of any injury, uses concise and descriptive terminology, reflects the mechanism of injury and biomechanical forces involved, guides choice of treatment, has easily recognizable clinical and radiological characteristics, describes and grades the severity of neurological injury, grades both osseous and ligamentous injury, and predicts the natural history and treatment end results (1).

Clinical importance of posterior vertebral height loss on plain radiography when conservatively treating osteoporotic vertebral fractures

PurposeTo predict spinal canal compromise, the assessment of plain radiography with magnetic resonance imaging (MRI) can aid the detection of vertebral body collapse and prevent the development of neurological deficits. MethodsPatients who suffered osteoporotic vertebral fractures (OVFs) between January 2012 and December 2014 underwent consecutive radiological assessments, including measurements of anterior height loss (AHL), posterior height loss (PHL), and the kyphotic angle (KA). The fracture morphology was classified by AOSpine thoracolumbar spine injury classification system. MRI was performed at the initial assessment and the extent of canal encroachment (CE) was calculated in all patients. Follow-up computed tomography (CT) or MRI was performed in patients exhibiting significant height loss in follow-up radiography. The fracture patterns in T1- and T2-weighted MRI were also assessed. ResultsA total of 485 patients visited our institute for treatment of OVFs and 97 were enrolled; 15 were male and 82 were female. The mean age at initial visit was 70.3±14.6years. The initial spinal CE was correlated with the initial PHL and the initial AHL. The follow-up CE was correlated with age, the initial PHL, and the difference between the initial and last PHL (ΔPHL(initial-last)). OVFs with both endplate fractures have a greater tendency of posterior wall collapse than those with single endplate fracture. On initial T1-weighted sagittal MRI, a diffuse low signal change pattern of the fractured vertebra was correlated with PHL. Delayed neurological deficits developed in four patients. These patients underwent surgical intervention. ConclusionsIn patients with simple compression fractures, attention should be paid to the posterior vertebral body and both endplates as well as the T1-weighted MRI findings to allow early detection of spinal canal compromise, which can have devastating consequences.

Reliability and reproducibility analysis of the AOSpine thoracolumbar spine injury classification system by Chinese spinal surgeons.

The objective of this study was to analyze the interobserver reliability and intraobserver reproducibility of the new AOSpine thoracolumbar spine injury classification system in young Chinese orthopedic surgeons with different levels of experience in spinal trauma. Previous reports suggest that the new AOSpine thoracolumbar spine injury classification system demonstrates acceptable interobserver reliability and intraobserver reproducibility. However, there are few studies in Asia, especially in China. The AOSpine thoracolumbar spine injury classification system was applied to 109 patients with acute, traumatic thoracolumbar spinal injuries by two groups of spinal surgeons with different levels of clinical experience. The Kappa coefficient was used to determine interobserver reliability and intraobserver reproducibility. The overall Kappa coefficient for all cases was 0.362, which represents fair reliability. The Kappa statistic was 0.385 for A-type injuries and 0.292 for B-type injuries, which represents fair reliability, and 0.552 for C-type injuries, which represents moderate reliability. The Kappa coefficient for intraobserver reproducibility was 0.442 for A-type injuries, 0.485 for B-type injuries, and 0.412 for C-type injuries. These values represent moderate reproducibility for all injury types. The raters in Group A provided significantly better interobserver reliability than Group B (P<0.05). There were no between-group differences in intraobserver reproducibility. This study suggests that the new AO spine injury classification system may be applied in day-to-day clinical practice in China following extensive training of healthcare providers. Further prospective studies in different healthcare providers and clinical settings are essential for validation of this classification system and to assess its utility.

Clinical and radiological factors affecting progressive collapse of acute osteoporotic compression spinal fractures

Osteoporotic compression spine fractures have a different clinical course and outcomes when compared to spinal fractures occurring in the younger population. Only a few studies have investigated the risk factors for progressive osteoporotic compression spine fractures. The purpose of this study was to investigate clinical and radiological factors related to progressive collapse following acute osteoporotic compression spine fractures. We retrospectively identified all patients treated for thoracolumbar fractures in our institution between January 2008 and July 2013. Included cases were examined by plain radiographs and CT scans. For each patient we classified the fracture according to the AOSpine Thoracolumbar Spine Injury Classification System. The difference between initial and final height loss and initial and final local kyphosis was documented as height loss difference and kyphotic angle difference. The presence of old fractures and intravertebral cleft were also documented. The study included 153 patients, comprising 102 women and 51 men. The mean patient age was 68.9years. The mean length of follow up was 15months. A statistically significant correlation was found between patient age, final height loss, height loss difference and kyphotic angle difference. Height loss difference and kyphotic angle difference were significantly correlated to type of fracture according to the AO classification system. The height loss difference was 18.1% in A1 type fractures, 27.1% in A2 type fractures, 24.2% in A3 type fractures and 25.7% in A4 type fractures. During a minimum 3-month follow up of conservative treatment for acute osteoporotic vertebral compression fractures, age and the AOSpine Thoracolumbar Spine Injury Classification System were predictive factors for progressive collapse.

Reliability assessment of AOSpine thoracolumbar spine injury classification system and Thoracolumbar Injury Classification and Severity Score (TLICS) for thoracolumbar spine injuries: results of a multicentre study.

The aim of this multicentre study was to determine whether the recently introduced AOSpine Classification and Injury Severity System has better interrater and intrarater reliability than the already existing Thoracolumbar Injury Classification and Severity Score (TLICS) for thoracolumbar spine injuries. Clinical and radiological data of 50 consecutive patients admitted at a single centre with a diagnosis of an acute traumatic thoracolumbar spine injury were distributed to eleven attending spine surgeons from six different institutions in the form of PowerPoint presentation, who classified them according to both classifications. After time span of 6weeks, cases were randomly rearranged and sent again to same surgeons for re-classification. Interobserver and intraobserver reliability for each component of TLICS and new AOSpine classification were evaluated using Fleiss Kappa coefficient (k value) and Spearman rank order correlation. Moderate interrater and intrarater reliability was seen for grading fracture type and integrity of posterior ligamentous complex (Fracture type: k=0.43±0.01 and 0.59±0.16, respectively, PLC: k=0.47±0.01 and 0.55±0.15, respectively), and fair to moderate reliability (k=0.29±0.01 interobserver and 0.44+/0.10 intraobserver, respectively) for total score according to TLICS. Moderate interrater (k=0.59±0.01) and substantial intrarater reliability (k=0.68±0.13) was seen for grading fracture type regardless of subtype according to AOSpine classification. Near perfect interrater and intrarater agreement was seen concerning neurological status for both the classification systems. Recently proposed AOSpine classification has better reliability for identifying fracture morphology than the existing TLICS. Additional studies are clearly necessary concerning the application of these classification systems across multiple physicians at different level of training and trauma centers to evaluate not only their reliability and reproducibility, but also the other attributes, especially the clinical significance of a good classification system.

Reliability of the evaluation of posterior ligamentous complex injury in thoracolumbar spine trauma with the use of computed tomography scan.

The AOSpine thoracolumbar (TL) spine injury classification system is based mainly on computed tomography (CT). The main purpose of this study was to evaluate the reliability of CT scan in the diagnosis of posterior ligamentous complex (PLC) injury in thoracolumbar spine trauma (TLST). We performed a cross-sectional study of 43 patients with TLST. CT scans were evaluated independently by three spine surgeons on two separate occasions, 2 months apart. The reliability of PLC injury parameters was assessed by the Kappa coefficient (κ) and the average percentage of these parameters was established. Injuries were classified according to the AOSpine classification as type A (compression), B (anterior and/or posterior tension band injuries) or C (dislocation) injury and the reliability of the classification was calculated. On average, PLC injury was identified in 91.4% of type B or C injuries. Tension band injury and dislocation were found in 90.5% of type B and 93.2% of type C injuries. The intraobserver reliability for the PLC injury parameters ranged from 0.518 to 1.000, except for increased interspinous distance (IID). Interobserver reliability ranged from 0.303 to 0.688. When the patients were evaluated as a whole, dislocation showed the highest κ (0.656 and 0.688). When type A or B injuries were assessed, the highest κ were found for IID (0.533 and 0.511) and tension band injury (0.486 and 0.452). The κ for AOSpine classification was 0.526 and 0.645 in both assessments. In this study, the use of CT scan as the only diagnostic tool could identify PLC injury in most cases and demonstrated satisfactory reliability. Dislocation could satisfactorily diagnose type C injury, while IID was the best parameter to differentiate between type A and B injuries.