Rigid spine injuries - A comprehensive review on diagnostic and therapeutic challenges.

Injuries to the rigid spine have a distinguished position in the broad spectrum of spinal injuries due to altered biomechanical properties. The rigid spine is more prone to fractures. Two ossification bone disorders that are of particular interest are Ankylosing Spondylitis (AS) and Diffuse Idiopathic Skeletal Hyperostosis (DISH). DISH is a non-inflammatory condition that leads to an anterolateral ossification of the spine. AS on the other hand is a chronic inflammatory disease that leads to cortical bone erosions and spinal ossifications. Both diseases gradually induce stiffening of the spine. The prevalence of DISH is age-related and is therefore higher in the older population. Although the prevalence of AS is not age-related the occurrence of spinal ossification is higher with increasing age. This association with age and the aging demographics in industrialized nations illustrate the need for medical professionals to be adequately informed and prepared. The aim of this narrating review is to give an overview on the diagnostic and therapeutic measures of the ankylosed spine. Because of highly unstable fracture configurations, injuries to the rigid spine are highly susceptible to neurological deficits. Diagnosing a fracture of the ankylosed spine on plain radiographs can be challenging. Moreover, since 8% of patients with ankylosing spine disorders (ASD) have multiple non-contagious fractures, a CT scan of the entire spine is highly recommended as the primary diagnostic tool. There are no consensus-based guidelines for the treatment of spinal fractures in ASD. The presence of neurological deficit or unstable fractures are absolute indications for surgical intervention. If conservative therapy is chosen, patients should be monitored closely to ensure that secondary neurologic deterioration does not occur. For the fractures that have to be treated surgically, stabilization of at least three segments above and below the fracture zone is recommended. These fractures mostly are treated via the posterior approach. Patients with AS or DISH share a significant risk for complications after a traumatic spine injury. The most frequent complications for patients with thoracolumbar burst fractures are respiratory failure, pseudoarthrosis, pneumonia, and implant failure.

Validation of the AO Spine CROST (Clinician Reported Outcome Spine Trauma) in the clinical setting.

PURPOSE: To evaluate feasibility, internal consistency, inter-rater reliability, and prospective validity of AO Spine CROST (Clinician Reported Outcome Spine Trauma) in the clinical setting. METHODS: Patients were included from four trauma centers. Two surgeons with substantial amount of experience in spine trauma care were included from each center. Two separate questionnaires were administered at baseline, 6-months and 1-year: one to surgeons (mainly CROST) and another to patients (AO Spine PROST-Patient Reported Outcome Spine Trauma). Descriptive statistics were used to analyze patient characteristics and feasibility, Cronbach's α for internal consistency. Inter-rater reliability through exact agreement, Kappa statistics and Intraclass Correlation Coefficient (ICC). Prospective analysis, and relationships between CROST and PROST were explored through descriptive statistics and Spearman correlations. RESULTS: In total, 92 patients were included. CROST showed excellent feasibility results. Internal consistency (α = 0.58-0.70) and reliability (ICC = 0.52 and 0.55) were moderate. Mean total scores between surgeons only differed 0.2-0.9 with exact agreement 48.9-57.6%. Exact agreement per CROST item showed good results (73.9-98.9%). Kappa statistics revealed moderate agreement for most CROST items. In the prospective analysis a trend was only seen when no concerns at all were expressed by the surgeon (CROST = 0), and moderate to strong positive Spearman correlations were found between CROST at baseline and the scores at follow-up (rs = 0.41-0.64). Comparing the CROST with PROST showed no specific association, nor any Spearman correlations (rs = -0.33-0.07). CONCLUSIONS: The AO Spine CROST showed moderate validity in a true clinical setting including patients from the daily clinical practice.

Understanding Decision Making as It Influences Treatment in Thoracolumbar Burst Fractures Without Neurological Deficit: Conceptual Framework and Methodology.

STUDY DESIGN: This paper presents a description of a conceptual framework and methodology that is applicable to the manuscripts that comprise this focus issue. OBJECTIVES: Our goal is to present a conceptual framework which is relied upon to better understand the processes through which surgeons make therapeutic decisions around how to treat thoracolumbar burst fractures (TL) fractures. METHODS: We will describe the methodology used in the AO Spine TL A3/4 Study prospective observational study and how the radiographs collected for this study were utilized to study the relationships between various variables that factor into surgeon decision making. RESULTS: With 22 expert spine trauma surgeons analyzing the acute CT scans of 183 patients with TL fractures we were able to perform pairwise analyses, look at reliability and correlations between responses and develop frequency tables, and regression models to assess the relationships and interactions between variables. We also used machine learning to develop decision trees. CONCLUSIONS: This paper outlines the overall methodological elements that are common to the subsequent papers in this focus issue.

Using Equipoise to Determine the Radiographic Characteristics Leading to Agreement on Best Treatment for Thoracolumbar Burst Fractures Without Neurologic Deficits.

STUDY DESIGN: Retrospective analysis of prospectively collected data. OBJECTIVES: Our goal was to assess radiographic characteristics associated with agreement and disagreement in treatment recommendation in thoracolumbar (TL) burst fractures. METHODS: A panel of 22 AO Spine Knowledge Forum Trauma experts reviewed 183 cases and were asked to: (1) classify the fracture; (2) assess degree of certainty of PLC disruption; (3) assess degree of comminution; and (4) make a treatment recommendation. Equipoise threshold used was 77% (77:23 distribution of uncertainty or 17 vs 5 experts). Two groups were created: consensus vs equipoise. RESULTS: Of the 183 cases reviewed, the experts reached full consensus in only 8 cases (4.4%). Eighty-one cases (44.3%) were included in the agreement group and 102 cases (55.7%) in the equipoise group. A3/A4 fractures were more common in the equipoise group (92.0% vs 83.7%, P < .001). The agreement group had higher degree of certainty of PLC disruption [35.8% (SD 34.2) vs 27.6 (SD 27.3), P < .001] and more common use of the M1 modifier (44.3% vs 38.3%, P < .001). Overall, the degree of comminution was slightly higher in the equipoise group [47.8 (SD 20.5) vs 45.7 (SD 23.4), P < .001]. CONCLUSIONS: The agreement group had a higher degree of certainty of PLC injury and more common use of M1 modifier (more type B fractures). The equipoise group had more A3/A4 type fractures. Future studies are required to identify the role of comminution in decision making as degree of comminution was slightly higher in the equipoise group.

What Factors Influence Surgeons in Decision-Making in Thoracolumbar Burst Fractures? A Survey-Based Investigation of a Panel of Spine Surgery Experts.

STUDY DESIGN: Cross-sectional survey study. OBJECTIVE: To investigate factors affecting decision-making in thoracolumbar burst-fractures without neurologic deficit. METHODS: A 40-question survey addressing expert-related, economic, and radiological factors was distributed to 30 international trauma experts. Descriptive statistics were used to assess the impact of these factors on operative or non-operative management preferences. RESULTS: Out of 30 experts, 27 completed the survey. The majority of respondents worked at level 1 trauma centers (81.5%) within university settings (77.8%). They were primarily orthopedic surgeons (66.7%) and had over 10 years of experience (70.4%). About 81% found distinguishing between A3 and A4 fractures relevant for decision-making. Most experts (59%) treated A3 fractures non-surgically, while only 30% treated A4 fractures conservatively. Compensation systems did not influence treatment recommendations, and hospital measures promoting surgeries did not significantly affect distribution. Radiological factors, such as local kyphosis (25/27), fracture comminution (23/27), overall sagittal balance (21/27), and spinal canal narrowing (20/27), influenced decisions. CONCLUSION: Incomplete burst fractures (A3) are predominantly treated non-surgically, while complete burst fractures (A4) are primarily treated surgically. Compensation, third-party incentives, and outpatient care did not significantly impact decision-making. Radiological factors beyond the AO Spine thoracolumbar classification system seem to be essential and warrant further evaluation.

Predictive Algorithm for Surgery Recommendation in Thoracolumbar Burst Fractures Without Neurological Deficits.

STUDY DESIGN: Predictive algorithm via decision tree. OBJECTIVES: Artificial intelligence (AI) remain an emerging field and have not previously been used to guide therapeutic decision making in thoracolumbar burst fractures. Building such models may reduce the variability in treatment recommendations. The goal of this study was to build a mathematical prediction rule based upon radiographic variables to guide treatment decisions. METHODS: Twenty-two surgeons from the AO Knowledge Forum Trauma reviewed 183 cases from the Spine TL A3/A4 prospective study (classification, degree of certainty of posterior ligamentous complex (PLC) injury, use of M1 modifier, degree of comminution, treatment recommendation). Reviewers' regions were classified as Europe, North/South America and Asia. Classification and regression trees were used to create models that would predict the treatment recommendation based upon radiographic variables. We applied the decision tree model which accounts for the possibility of non-normal distributions of data. Cross-validation technique as used to validate the multivariable analyses. RESULTS: The accuracy of the model was excellent at 82.4%. Variables included in the algorithm were certainty of PLC injury (%), degree of comminution (%), the use of M1 modifier and geographical regions. The algorithm showed that if a patient has a certainty of PLC injury over 57.5%, then there is a 97.0% chance of receiving surgery. If certainty of PLC injury was low and comminution was above 37.5%, a patient had 74.2% chance of receiving surgery in Europe and Asia vs 22.7% chance in North/South America. Throughout the algorithm, the use of the M1 modifier increased the probability of receiving surgery by 21.4% on average. CONCLUSION: This study presents a predictive analytic algorithm to guide decision-making in the treatment of thoracolumbar burst fractures without neurological deficits. PLC injury assessment over 57.5% was highly predictive of receiving surgery (97.0%). A high degree of comminution resulted in a higher chance of receiving surgery in Europe or Asia vs North/South America. Future studies could include clinical and other variables to enhance predictive ability or use machine learning for outcomes prediction in thoracolumbar burst fractures.

Interobserver Reliability in the Classification of Thoracolumbar Fractures Using the AO Spine TL Injury Classification System Among 22 Clinical Experts in Spine Trauma Care.

STUDY DESIGN: Reliability study utilizing 183 injury CT scans by 22 spine trauma experts with assessment of radiographic features, classification of injuries and treatment recommendations. OBJECTIVES: To assess the reliability of the AOSpine TL Injury Classification System (TLICS) including the categories within the classification and the M1 modifier. METHODS: Kappa and Intraclass correlation coefficients were produced. Associations of various imaging characteristics (comminution, PLC status) and treatment recommendations were analyzed through regression analysis. Multivariable logistic regression modeling was used for making predictive algorithms. RESULTS: Reliability of the AO Spine TLICS at differentiating A3 and A4 injuries (N = 71) (K = .466; 95% CI .458 - .474; P < .001) demonstrated moderate agreement. Similarly, the average intraclass correlation coefficient (ICC) amongst A3 and A4 injuries was excellent (ICC = .934; 95% CI .919 - .947; P < .001) and the ICC between individual measures was moderate (ICC = .403; 95% CI .351 - .461; P < .001). The overall agreement on the utilization of the M1 modifier amongst A3 and A4 injuries was fair (K = .161; 95% CI .151 - .171; P < .001). The ICC for PLC status in A3 and A4 injuries averaged across all measures was excellent (ICC = .936; 95% CI .922 - .949; P < .001). The M1 modifier suggests respondents are nearly 40% more confident that the PLC is injured amongst all injuries. The M1 modifier was employed at a higher frequency as injuries were classified higher in the classification system. CONCLUSIONS: The reliability of surgeons differentiating between A3 and A4 injuries in the AOSpine TLICS is substantial and the utilization of the M1 modifier occurs more frequently with higher grades in the system.

Expert Opinion, Real-World Classification, and Decision-Making in Thoracolumbar Burst Fractures Without Neurologic Deficits?

STUDY DESIGN: Retrospective analysis of prospectively collected data. OBJECTIVES: To compare decision-making between an expert panel and real-world spine surgeons in thoracolumbar burst fractures (TLBFs) without neurological deficits and analyze which factors influence surgical decision-making. METHODS: This study is a sub-analysis of a prospective observational study in TL fractures. Twenty two experts were asked to review 183 CT scans and recommend treatment for each fracture. The expert recommendation was based on radiographic review. RESULTS: Overall agreement between the expert panel and real-world surgeons regarding surgery was 63.2%. In 36.8% of cases, the expert panel recommended surgery that was not performed in real-world scenarios. Conversely, in cases where the expert panel recommended non-surgical treatment, only 38.6% received non-surgical treatment, while 61.4% underwent surgery. A separate analysis of A3 and A4 fractures revealed that expert panel recommended surgery for 30% of A3 injuries and 68% of A4 injuries. However, 61% of patients with both A3 and A4 fractures received surgery in the real world. Multivariate analysis demonstrated that a 1% increase in certainty of PLC injury led to a 4% increase in surgery recommendation among the expert panel, while a .2% increase in the likelihood of receiving surgery in the real world. CONCLUSION: Surgical decision-making varied between the expert panel and real-world treating surgeons. Differences appear to be less evident in A3/A4 burst fractures making this specific group of fractures a real challenge independent of the level of expertise.

The AO Spine Thoracolumbar Injury Classification System and Treatment Algorithm in Decision Making for Thoracolumbar Burst Fractures Without Neurologic Deficit.

STUDY DESIGN: Prospective Observational Study. OBJECTIVE: To determine the alignment of the AO Spine Thoracolumbar Injury Classification system and treatment algorithm with contemporary surgical decision making. METHODS: 183 cases of thoracolumbar burst fractures were reviewed by 22 AO Spine Knowledge Forum Trauma experts. These experienced clinicians classified the fracture morphology, integrity of the posterior ligamentous complex and degree of comminution. Management recommendations were collected. RESULTS: There was a statistically significant stepwise increase in rates of operative management with escalating category of injury (P < .001). An excellent correlation existed between recommended expert management and the actual treatment of each injury category: A0/A1/A2 (OR 1.09, 95% CI 0.70-1.69, P = .71), A3/4 (OR 1.62, 95% CI 0.98-2.66, P = .58) and B1/B2/C (1.00, 95% CI 0.87-1.14, P = .99). Thoracolumbar A4 fractures were more likely to be surgically stabilized than A3 fractures (68.2% vs 30.9%, P < .001). A modifier indicating indeterminate ligamentous injury increased the rate of operative management when comparing type B and C injuries to type A3/A4 injuries (OR 39.19, 95% CI 20.84-73.69, P < .01 vs OR 27.72, 95% CI 14.68-52.33, P < .01). CONCLUSIONS: The AO Spine Thoracolumbar Injury Classification system introduces fracture morphology in a rational and hierarchical manner of escalating severity. Thoracolumbar A4 complete burst fractures were more likely to be operatively managed than A3 fractures. Flexion-distraction type B injuries and translational type C injuries were much more likely to have surgery recommended than type A fractures regardless of the M1 modifier. A suspected posterior ligamentous injury increased the likelihood of surgeons favoring surgical stabilization.

From Radiographic Evaluation to Treatment Decisions in Neurologically Intact Patients With Thoraco-lumbar Burst Fractures.

We propose that the key to improving care for these patients is to truly understand the processes that take place from the interpretation of radiographic findings, through the assessment of the severity of various injuries, to inclusion within a classification category and finally to selecting a specific treatment.

The changing landscape of spinal injuries: A narrative review.

In the past, spinal trauma was frequent in high- and middle-income regions of the world with high rates of automobility and was considered a "young men's disease." However, over the last 2 decades, both of these factors have changed dramatically. This has had important implications for our methods of diagnosis, treatment, and the organization of care.

The Diagnostic Process of Spinal Post-traumatic Deformity: An Expert Survey of 7 Cases, Consensus on Clinical Relevance Does Exist.

STUDY DESIGN: Survey of cases. OBJECTIVE: To evaluate the opinion of experts in the diagnostic process of clinically relevant Spinal Post-traumatic Deformity (SPTD). SUMMARY OF BACKGROUND DATA: SPTD is a potential complication of spine trauma that can cause decreased function and quality of life impairment. The question of when SPTD becomes clinically relevant is yet to be resolved. METHODS: The survey of 7 cases was sent to 31 experts. The case presentation was medical history, diagnostic assessment, evaluation of diagnostic assessment, diagnosis, and treatment options. Means, ranges, percentages of participants, and descriptive statistics were calculated. RESULTS: Seventeen spinal surgeons reviewed the presented cases. The items' fracture type and complaints were rated by the participants as more important, but no agreement existed on the items of medical history. In patients with possible SPTD in the cervical spine (C) area, participants requested a conventional radiograph (CR) (76%-83%), a flexion/extension CR (61%-71%), a computed tomography (CT)-scan (76%-89%), and a magnetic resonance (MR)-scan (89%-94%). In thoracolumbar spine (ThL) cases, full spine CR (89%-100%), CT scan (72%-94%), and MR scan (65%-94%) were requested most often. There was a consensus on 5 out of 7 cases with clinically relevant SPTD (82%-100%). When consensus existed on the diagnosis of SPTD, there was a consensus on the case being compensated or decompensated and being symptomatic or asymptomatic. CONCLUSIONS: There was strong agreement in 5 out of 7 cases on the presence of the diagnosis of clinically relevant SPTD. Among spine experts, there is a strong consensus to use CT scan and MR scan, a cervical CR for C-cases, and a full spine CR for ThL-cases. The lack of agreement on items of the medical history suggests that a Delphi study can help us reach a consensus on the essential items of clinically relevant SPTD. LEVEL OF EVIDENCE: Level V.

Spinal Post-traumatic Deformity: An International Expert Survey Among AO Spine Knowledge Forum Members.

STUDY DESIGN: Survey among spine experts. OBJECTIVE: To investigate the different views and opinions of clinically relevant spinal post-traumatic deformity (SPTD). SUMMARY OF BACKGROUND DATA: There is no clear definition of clinically relevant SPTD. This leads to a wide variation in characteristics used for diagnosis and treatment indications of SPTD. To understand the current concepts of SPTD a survey was conducted among spine trauma surgeons. METHODS: Members of the AO Spine Knowledge Forum Trauma participated in an online survey. The survey was divided in 4 domains: Demographics, criteria to define SPTD, risk factors, and management. The data were collected anonymously and analyzed using descriptive statistics, absolute, and relative frequencies. Consensus on dichotomous outcomes was set to 80% of agreement. RESULTS: Fifteen members with extensive experience in treatment of spinal trauma participated, representing the 5 AO Spine Regions. Back pain was the only criterion for definition of SPTD with complete agreement. Consensus (≥80%) was reached for kyphotic angulation outside normative ranges and impaired function. Eighty-seven percent and 100% agreed that a full-spine conventional radiograph was necessary in diagnosing and treating SPTD, respectively. The "missed B-type injury" was rated at most important by all but 1 participant. There was no agreement on other risk factors leading to clinically relevant SPTD. Concerning the management, all participants agreed that an asymptomatic patient should not undergo surgical treatment and that neurological deficit is an absolute surgical indication. For most of the participants the preferred surgical treatment of acute injury in all spine regions but the subaxial region is posterior fixation. CONCLUSION: Some consensus exists among leading experts in the field of spine trauma care concerning the definition, diagnosis, risk factors, and management of SPTD. This study acts as the foundation for a Delphi study among the global spine community.

AO Spine upper cervical injury classification system: a description and reliability study.

BACKGROUND CONTEXT: Prior upper cervical spine injury classification systems have focused on injuries to the craniocervical junction (CCJ), atlas, and dens independently. However, no previous system has classified upper cervical spine injuries using a comprehensive system incorporating all injuries from the occiput to the C2-3 joint. PURPOSE: To (1) determine the accuracy of experts at correctly classifying upper cervical spine injuries based on the recently proposed AO Spine Upper Cervical Injury Classification System (2) to determine their interobserver reliability and (3) identify the intraobserver reproducibility of the experts. STUDY DESIGN/SETTING: International Multi-Center Survey. PATIENT SAMPLE: A survey of international spine surgeons on 29 unique upper cervical spine injuries. OUTCOME MEASURES: Classification accuracy, interobserver reliability, intraobserver reproducibility. METHODS: Thirteen international AO Spine Knowledge Forum Trauma members participated in two live webinar-based classifications of 29 upper cervical spine injuries presented in random order, four weeks apart. Percent agreement with the gold-standard and kappa coefficients (ƙ) were calculated to determine the interobserver reliability and intraobserver reproducibility. RESULTS: Raters demonstrated 80.8% and 82.7% accuracy with identification of the injury classification (combined location and type) on the first and second assessment, respectively. Injury classification intraobserver reproducibility was excellent (mean, [range] ƙ=0.82 [0.58-1.00]). Excellent interobserver reliability was found for injury location (ƙ = 0.922 and ƙ=0.912) on both assessments, while injury type was substantial (ƙ=0.689 and 0.699) on both assessments. This correlated to a substantial overall interobserver reliability (ƙ=0.729 and 0.732). CONCLUSIONS: Early phase validation demonstrated classification of upper cervical spine injuries using the AO Spine Upper Cervical Injury Classification System to be accurate, reliable, and reproducible. Greater than 80% accuracy was detected for injury classification. The intraobserver reproducibility was excellent, while the interobserver reliability was substantial.

Long-Term Reliability and Validity of the AO Spine PROST (Patient-Reported Outcome Spine Trauma).

STUDY DESIGN: Cross-sectional validation study. OBJECTIVE: The aim was to validate the AO Spine Patient-Reported Outcome Spine Trauma (PROST) at a minimum of 12 months posttrauma and to evaluate patient characteristics, types of spine fractures, and treatment strategies as determinants of AO Spine PROST scores. SUMMARY OF BACKGROUND DATA: The reliability and validity of the AO Spine PROST as a measure of health-related quality of life for more than 12 months after onset of spine trauma is unclear. MATERIALS AND METHODS: Patients with a traumatic spine injury were recruited from a level-1 trauma center. They were asked to complete the AO Spine PROST, EuroQoL 5D-5L (EQ-5D-5L), and either Oswestry disability index (ODI) or neck disability index (NDI) for concurrent validity. Internal consistency was assessed by calculating the Cronbach α and item-total correlation coefficients. Test-retest reliability was evaluated using intraclass correlation coefficients. Spearman correlation tests were performed for the AO Spine PROST in correlation with the EQ-5D-5L, and either ODI or NDI. Determinants for AO Spine PROST score were analyzed using multivariate regression models. RESULTS: A total of 175 patients participated in the cross-sectional arm and 49 in the test-retest arm of the study. Median duration of follow-up was 94.5 months. No floor or ceiling effects were seen. Internal consistency was excellent (α=0.98, item-total correlation coefficient: 0.73-0.91) as well as test-retest reliability (intraclass correlation coefficient=0.81). Satisfactory correlations were seen for the EQ-5D-5L (0.76; P <0.001), ODI (0.69; P <0.001), and NDI (0.68; P <0.001) with the AO Spine PROST. Multivariate linear regression models showed that having ≥1 comorbidities, duration of return to work within the range of 7 to 43 months and no return to work were significant independent determinants for a worse AO Spine PROST score. CONCLUSIONS: Very good long-term reliability and validity results were found for the AO Spine PROST.

Variations in management of A3 and A4 cervical spine fractures as designated by the AO Spine Subaxial Injury Classification System.

OBJECTIVE: Optimal management of A3 and A4 cervical spine fractures, as defined by the AO Spine Subaxial Injury Classification System, remains controversial. The objectives of this study were to determine whether significant management variations exist with respect to 1) fracture location across the upper, middle, and lower subaxial cervical spine and 2) geographic region, experience, or specialty. METHODS: A survey was internationally distributed to 272 AO Spine members across six geographic regions (North America, South America, Europe, Africa, Asia, and the Middle East). Participants' management of A3 and A4 subaxial cervical fractures across cervical regions was assessed in four clinical scenarios. Key characteristics considered in the vignettes included degree of neurological deficit, pain severity, cervical spine stability, presence of comorbidities, and fitness for surgery. Respondents were also directly asked about their preferences for operative management and misalignment acceptance across the subaxial cervical spine. RESULTS: In total, 155 (57.0%) participants completed the survey. Pooled analysis demonstrated that surgeons were more likely to offer operative intervention for both A3 (p < 0.001) and A4 (p < 0.001) fractures located at the cervicothoracic junction compared with fractures at the upper or middle subaxial cervical regions. There were no significant variations in management for junctional incomplete (p = 0.116) or complete (p = 0.342) burst fractures between geographic regions. Surgeons with more than 10 years of experience were more likely to operatively manage A3 (p < 0.001) and A4 (p < 0.001) fractures than their younger counterparts. Neurosurgeons were more likely to offer surgical stabilization of A3 (p < 0.001) and A4 (p < 0.001) fractures than their orthopedic colleagues. Clinicians from both specialties agreed regarding their preference for fixation of lower junctional A3 (p = 0.866) and A4 (p = 0.368) fractures. Overall, surgical fixation was recommended more often for A4 than A3 fractures in all four scenarios (p < 0.001). CONCLUSIONS: The subaxial cervical spine should not be considered a single unified entity. Both A3 and A4 fracture subtypes were more likely to be surgically managed at the cervicothoracic junction than the upper or middle subaxial cervical regions. The authors also determined that treatment strategies for A3 and A4 subaxial cervical spine fractures varied significantly, with the latter demonstrating a greater likelihood of operative management. These findings should be reflected in future subaxial cervical spine trauma algorithms.

Diagnostic accuracy of computed tomography angiography (CTA) for diagnosing blunt cerebrovascular injury in trauma patients: a systematic review and meta-analysis.

OBJECTIVES: Previous literature showed that the diagnostic accuracy of computed tomographic angiography (CTA) is not equally comparable with that of the rarely used golden standard of digital subtraction angiography (DSA) for detecting blunt cerebrovascular injuries (BCVI) in trauma patients. However, advances in CTA technology may prove CTA to become equally accurate. This study investigated the diagnostic accuracy of CTA in detecting BCVI in comparison with DSA in trauma patients. METHODS: An electronic database search was performed in PubMed, EMBASE, and Cochrane Library. Summary estimates of sensitivity, specificity, positive and negative likelihood, diagnostic odds ratio, and 95% confidence intervals were determined using a bivariate random-effects model. RESULTS: Of the 3293 studies identified, 9 met the inclusion criteria. Pooled sensitivity was 64% (95% CI, 53-74%) and specificity 95% (95% CI, 87-99%) The estimated positive likelihood ratio was 11.8 (95%, 5.6-24.9), with a negative likelihood ratio of 0.38 (95%, 0.30-0.49) and a diagnostic odds ratio of 31 (95%, 17-56). CONCLUSION: CTA has reasonable specificity but low sensitivity when compared to DSA in diagnosing any BCVI. An increase in channels to 64 slices did not yield better sensitivity. There is a risk for underdiagnosis of BCVI when only using DSA to confirm CTA-positive cases, especially in those patients with low-grade injuries. KEY POINTS: • Low sensitivity and high specificity were seen in identifying BCVI with CTA as compared to DSA. • Increased CTA detector channels (≤ 64) did not lead to higher sensitivity when detecting BCVI. • The use of CTA instead of DSA may lead to underdiagnosis and, consequently, undertreatment of BCVI.

Blunt cerebrovascular injury: incidence and long-term follow-up.

PURPOSE: Blunt cerebrovascular injuries (BCVI), which can result in ischemic stroke, are identified in 1-2% of all blunt trauma patients. Computed tomography angiography (CTA) scanning has improved and is the diagnostic modality of choice in BCVI suspected patients. Data about long-term functional outcomes and the incidence of ischemic stroke after BCVI are limited. The aim of this study was to determine BCVI incidence in relation to imaging modality improvements and to determine long-term functional outcomes. METHODS: All consecutive trauma patients from 2007 to 2016 with BCVI were identified from the level 1 trauma center prospective trauma database. Three periods were identified where CTA diagnostic modalities for trauma patients were improved. Long-term functional outcomes using the EuroQol six-dimensional (EQ-6D™) were determined. RESULTS: Seventy-one BCVI patients were identified among the 12.122 (0.59%) blunt trauma patients. In the first period BCVI incidence among the overall study cohort, polytrauma, basilar skull fracture and cervical trauma subgroups was found to be 0.3%, 0.9%, 1.2%, 4.6%, respectively, which more than doubled towards the third period (0.8, 2.4, 1.9 and 8.5% respectively). Ischemic stroke as a result of BCVI was found in 20 patients (28%). In-hospital stroke rate was lower in patients receiving antiplatelet therapy (p < 0.01). Six in-hospital deaths were BCVI related. Long-term follow-up (follow-up rate of 83%) demonstrated lower functional outcomes compared to Dutch reference populations (p < 0.01). Ischemic stroke was identified as a major cause of functional impairment at long-term follow-up. CONCLUSIONS: Improved CTA diagnostic modalities have increased BCVI incidence. Furthermore, BCVI patients reported significant functional impairment at long-term follow-up. Antiplatelet therapy showed a significant effect on in-hospital stroke rate reduction.

The Current Status of Spinal Posttraumatic Deformity: A Systematic Review.

STUDY DESIGN: Systematic Review. OBJECTIVE: To systematically analyze the definitions and descriptions in literature of "Spinal Posttraumatic Deformity" (SPTD) in order to support the development of a uniform and comprehensive definition of clinically relevant SPTD. METHODS: A literature search in 11 international databases was performed using "deformity" AND "posttraumatic" and its synonyms. When an original definition or a description of SPTD (Patient factors, Radiological outcomes, Patient Reported Outcome Measurements and Surgical indication) was present the article was included. The retrieved articles were assessed for methodological quality and the presented data was extracted. RESULTS: 46 articles met the inclusion criteria. "Symptomatic SPTD" was mentioned multiple times as an entity, however any description of "symptomatic SPTD" was not found. Pain was mentioned as a key factor in SPTD. Other patient related parameters were (progression of) neurological deficit, bone quality, age, comorbidities and functional disability. Various ways were used to determine the amount of deformity on radiographs. The amount of deformity ranged from not deviant for normal to >30°. Sagittal balance and spinopelvic parameters such as the Pelvic Incidence, Pelvic Tilt and Sacral Slope were taken into account and were used as surgical indicators and preoperative planning. The Visual Analog Scale for pain and the Oswestry Disability Index were used mostly to evaluate surgical intervention. CONCLUSION: A clear-cut definition or consensus is not available in the literature about clinically relevant SPTD. Our research acts as the basis for international efforts for the development of a definition of SPTD.

Development and reliability of the AOSpine CROST (Clinician Reported Outcome Spine Trauma): a tool to evaluate and predict outcomes from clinician's perspective.

PURPOSE: To report on the development of AOSpine CROST (Clinician Reported Outcome Spine Trauma) and results of an initial reliability study. METHODS: The AOSpine CROST was developed using an iterative approach of multiple cycles of development, review, and revision including an expert clinician panel. Subsequently, a reliability study was performed among an expert panel who were provided with 20 spine trauma cases, administered twice with 4-week interval. The results of the developmental process were analyzed using descriptive statistics, the reliability per parameter using Kappa statistics, inter-rater rater agreement using intraclass correlation coefficient (ICC), and internal consistency using Cronbach's α. RESULTS: The AOSpine CROST was developed and consisted of 10 parameters, 2 of which are only applicable for surgically treated patents ('Wound healing' and 'Implants'). A dichotomous scoring system ('yes' or 'no' response) was incorporated to express expected problems for the short term and long term. In the reliability study, 16 (84.2%) participated in the first round and 14 (73.7%) in the second. Intra-rater reliability was fair to good for both time points (κ = 0.40-0.80 and κ = 0.31-0.67). Results of inter-rater reliability were lower (κ = 0.18-0.60 and κ = 0.16-0.46). Inter-rater agreement for total scores showed moderate results (ICC = 0.52-0.60), and the internal consistency was acceptable (α = 0.76-0.82). CONCLUSIONS: The AOSpine CROST, an outcome tool for the surgeons, was developed using an iterative process. An initial reliability analysis showed fair to moderate results and acceptable internal consistency. Further clinical validation studies will be performed to further validate the tool.