Thoracolumbar Burst Fracture: McCormack Load-sharing Classification: Systematic Review and Single-arm Meta-analysis.

STUDY DESIGN: A systematic review and single-arm meta-analysis of randomized clinical trials. OBJECTIVE: The aim of this study was to evaluate whether the load-sharing classification (LSC) is reliable to predict the best surgical approach for thoracolumbar burst fracture (TBF). SUMMARY OF BACKGROUND DATA: There is no previous review evaluating the efficacy of the use of LSC as a guide in the surgical treatment of burst fractures. METHODS: On April 19th, 2019, a broad search was performed in the following databases: EMBASE, PubMed, Cochrane, SCOPUS, Web of Science, LILACS, and gray literature. This study was registered on the International Prospective Register of Systematic Reviews. We included clinical trials involving patients with TBF undergoing posterior surgical treatment, classified by load-sharing score, and that enabled the analysis of the outcomes loss of segmental kyphosis and implant failure (IF). We performed random- or fixed-effects models meta-analyses depending on the data homogeneity. Heterogeneity between studies was estimated by I2 and τ2 statistics. RESULTS: The search identified 189 references, out of which nine studies were eligible for this review. All articles presenting LSC up to 6 proved to be reliable in indicating that only posterior instrumentation is necessary, without screw failures or loss of kyphosis correction. For cases where the LSC was >6, only 2.5% of the individuals presented IF upon posterior approach alone. For loss of kyphosis correction, only 5% of patients had this outcome where LSC >6. For both outcomes together, we had 6% of postoperative problems (I2 = 77%, τ2 < 0.0015, P < 0.01). CONCLUSION: Load-sharing scores up to 6 are 100% reliable, only requiring posterior instrumentation for stabilization. For scores >6, the risk of implant breakage and loss of kyphosis correction in posterior fixation alone is low. Thus, other factors should be considered to define the best surgical approach to be adopted.Level of Evidence: 1.

Computational techniques to segment and classify lumbar compression fractures.

Vertebral fractures are important indicators of osteoporosis. Fractures with partial collapse of vertebral bodies are referred to as vertebral compression fractures (VCFs) that are usually non-traumatic in nature. Some common causes of VCFs are trauma, bone failure related to osteoporosis (benign) and metastatic cancer (malignant). This paper aims at developing a system for computer-aided diagnosis to help in the detection, labeling and segmentation of lumbar vertebral body (VB) and to further classify each VB into normal, malignant and benign VCFs. After the initial preprocessing, morphological, shape and angular features are used in the detection, labeling and segmentation steps. Various shape and statistical texture features are extracted from the segmented VB and are fed to the classifier for the final decision. The segmentation and classification results obtained were compared with the ground truth manual segmentation of the lumbar VB and the decision labels of the fractures provided by the experts. The dice similarity coefficient (DSC) for segmentation reached up to 94.27%, and the classification results show that shape and texture features together are able to correctly classify with an accuracy rate of 95.34%. The final outcomes are expected to be useful in the analysis of vertebral compression fractures.

High-energy Lateral Compression Type 1 Injuries of the Pelvis: A Spectrum of Injury.

Lateral compression type 1 pelvic fractures comprise a spectrum of injuries of varying stability. The clinician should be cognizant of signs and symptoms of instability including complete sacral fractures, bilateral ramus fractures, displacement greater than 1 cm, high-energy mechanism, and inability to bear weight. Management of these injuries is controversial, but the clinician should consider examination under anesthesia and potentially surgical stabilization.

A special superior cortex compressive fracture of femoral neck: Two case reports.

RATIONALE: Garden type I femoral neck fractures are incomplete stable fractures with impaction in valgus fractures that the question of whether there exists Garden type I femoral neck fracture is currently uncertain. There is still disagreement on the existence of the Garden type I fractures. PATIENT CONCERNS: Herein we report 2 cases with the Garden type I femoral neck fractures. Both of them had a history of simple fall. DIAGNOSES: The X-ray showed incomplete fractures of the femoral neck and the Garden classification is type I. Further computed tomography and magnetic resonance imaging were used to confirm the diagnosis of this type fracture, which showed that the superior cortex of femoral neck was discontinuous and the inferior cortex remains intact. INTERVENTIONS: The conservative treatment schedule including immobilization of the affected lower limb, strict bed rest, bed-to-wheelchair transfer training, and half-to-full weight bearing mobilization were chosen to treat the patients. OUTCOMES: Both of them achieved fracture union with conservative treatment at 3-month follow-up. No secondary displacement, signal of osteonecrosis of the femoral head or other complications occurred during 24-month follow-up in 2 cases. LESSONS: Although the Garden type I femoral neck fractures are rare, our report is in line with the real existence of it.

The impact of magnetic resonance imaging in the diagnostic and classification process of osteoporotic vertebral fractures.

INTRODUCTION: Standard radiographs are still considered as the gold standard for the early assessment of thoraco-lumbar osteoporotic vertebral fractures (OVFs), although several studies demonstrated superior accuracy of magnetic resonance imaging (MRI) in the diagnostic process of OVFs. The aim of this study was to quantify the misdiagnosis rate of OVFs and analyse the impact of MRI on early diagnosis and classification, compared to standard radiographs alone. MATERIALS AND METHODS: A total of 173 patients were enrolled in this study. All participants were 55 years of age or older (60 years for men) and complained acute back pain with suspected thoracolumbar OVFs without history of high-energy trauma. Diagnosis of OVF was initially performed on standard radiographs obtained in the emergency room. Then, all the patients underwent MRI scan with short-tau inversion recovery (STIR) sequencing within 7 days. We compared the level and number of fractures identified on standard radiographs with the MRI scan results. The discordance between radiographic and MRI diagnosis was quantified. Fractures were classified according to AO Spine Classification. RESULTS: Mean age of the study participant was 74.2 years (range 55-92). They were 100 males and 73 females. MRI modified initial diagnosis in 52% (90/173) of our patients: in 43.9% of patients MRI identified one or more new thoracolumbar fracture. In 14 cases (8.1%) MRI disproved the evidence of any thoracolumbar fracture, even those recognized at plain X-rays. Bone bruise was detected by MRI in 19 vertebral bodies in 8 patients (4.6%) at levels that were classified as unremarkable on X-ray alone. In addition, 63 patients (36.4%) presented a total of 93 old fractures. The classification of fracture pattern after MRI changed in 28.90% of the patients (changes mostly involved AO type A1 patterns). CONCLUSIONS: Underdiagnosis of osteoporotic vertebral fractures is a common problem due to a lack of radiographic detection. Our results showed that the extensive use of MRI imaging allows better accuracy in the diagnostic process and in the classification assessment, compared to conventional radiographs. Further investigation should provide additional information about the impact of early MRI on treatment and management of elderly patients with suspected OVFs, including the decision to hospitalize or not, and how it could affect clinical outcome and social costs.

Cooperative strategy for a dynamic ensemble of classification models in clinical applications: the case of MRI vertebral compression fractures.

PURPOSE: In clinical practice, the constructive consultation among experts improves the reliability of the diagnosis and leads to the definition of the treatment plan for the patient. Aggregation of the different opinions collected by many experts can be performed at the level of patient information, abnormality delineation, or final assessment. METHODS: In this study, we present a novel cooperative strategy that exploits the dynamic contribution of the classification models composing the ensemble to make the final class assignment. As a proof of concept, we applied the proposed approach to the assessment of malignant infiltration in 103 vertebral compression fractures in magnetic resonance images. RESULTS: The results obtained with repeated random subsampling and receiver operating characteristic analysis indicate that the cooperative system statistically improved ([Formula: see text]) the classification accuracy of individual modules as well as of that based on the manual segmentation of the fractures provided by the experts. CONCLUSIONS: The performances have been also compared with those obtained with those of standard ensemble classification algorithms showing superior results.

Shape, texture and statistical features for classification of benign and malignant vertebral compression fractures in magnetic resonance images.

PURPOSE: Vertebral compression fractures (VCFs) result in partial collapse of vertebral bodies. They usually are nontraumatic or occur with low-energy trauma in the elderly secondary to different etiologies, such as insufficiency fractures of bone fragility in osteoporosis (benign fractures) or vertebral metastasis (malignant fractures). Our study aims to classify VCFs in T1-weighted magnetic resonance images (MRI). METHODS: We used the median sagittal planes of lumbar spine MRIs from 63 patients (38 women and 25 men) previously diagnosed with VCFs. The lumbar vertebral bodies were manually segmented and statistical features of gray levels were computed from the histogram. We also extracted texture and shape features to analyze the contours of the vertebral bodies. In total, 102 lumbar VCFs (53 benign and 49 malignant) and 89 normal lumbar vertebral bodies were analyzed. The k-nearest-neighbor method, a neural network with radial basis functions, and a naïve Bayes classifier were used with feature selection. We compared the classification obtained by these classifiers with the final diagnosis of each case, including biopsy for the malignant fractures and clinical and laboratory follow up for the benign fractures. RESULTS: The results obtained show an area under the receiver operating characteristic curve of 0.97 in distinguishing between normal and fractured vertebral bodies, and 0.92 in discriminating between benign and malignant fractures. CONCLUSIONS: The proposed classification methods based on shape, texture, and statistical features have provided high accuracy and may assist in the diagnosis of VCFs.

Thoracolumbar compression fractures - experimental study and clinical case analysis.

BACKGROUND: Epiphyseal stabilisation and reduction with the use of ligamentotaxis are employed in the surgical treatment of compression fractures of the spine. The mechanism of ligamentotaxis has not been fully elucidated. Therefore, it is fundamental to analyse various clinical data to determine the study area relevant to the elucidation of this mechanism. MATERIAL AND METHODS: We developed criteria for data selection from patient medical records for a newly-created database regarding cases of thoracolumbar vertebral body fractures. We also developed rules for assigning cases to a specific group according to the AO/Magerl classification. The methodology of fracture assessment involved the results of visualization of the spinal segment including the injured vertebral bodies and their virtual and material models. To this end, preoperative CT images were processed with specialised computer software. RESULTS: A biomechanically-oriented classification of clinical cases in the database was carried out based on 3D-CAD virtual models of spinal segments and models of individual injured vertebral bodies and RP material models in FDM technology. We indicated cases in which ligamentotaxis could be of use. CONCLUSIONS: Our analysis of ligamentotaxis research shows that the focus should be on cases of comminuted and nonosteoporotic fractures. Supporting work-up with 3D-CAD virtual and RP material models of spinal structures appears to be useful not only for the purposes of the present study but also in medical practice.

Early mobilization with customized TLSO brace in thoracolumbar burst fractures.

OBJECTIVE: This study aimed to research the effectiveness of customized thoracolumbosacral orthosis treatment for stable burst type thoracolumbar vertebral fractures without neurological deficits. METHODS: The study included 26 patients (14 males, 12 females; mean age: 46.03 years; range: 18 to 64 years) conservatively treated for thoracolumbar (T11-L2) burst type vertebral fractures according to Denis classification between 2002 and 2009. Etiology were a fall from various heights in 12 patients (46.2%), motor vehicle accidents as an occupant in 7 (26.9%) and as a pedestrian in 4 (15.4%), and simple fall in 3 (11.5%). None of the patients had neurologic deficit and no damage was found in the posterior ligamentous complex in MRI evaluations. Denis pain and functional scales were used in the clinical evaluation. Local kyphosis angle, sagittal index and height loss percentage were measured in the radiologic evaluation. Post-fracture and follow-up values were compared. Mean follow-up period was 41.30 (range: 14 to 80) months. RESULTS: Mean pain and functional scores were 1.65 and 1.15 points, respectively, at the final follow-up. Twenty patients returned to their pre-trauma work and activities completely and six patients with small limitations. Mean period for returning to work was 3.64 (range: 2 to 6) months. Local kyphosis angle, sagittal index and height loss percentage values increased significantly at follow-up (p<0.05). CONCLUSION: The conservative treatment of stable thoracolumbar burst fractures is widely accepted. Early mobilization with customized TLSO brace appears to produce effective functional results despite loss of vertebral body height.

Reproducibility of three classifications of proximal humeral fractures / Reprodutibilidade de três classificações de fraturas na região proximal do úmero

OBJECTIVE: To propose a new system for classifying proximal humeral neck fractures, and to evaluate intra- and interobserver agreement using the Neer system that is the most commonly used in the area and the Arbeit Gemeinschaft für Osteosynthesefragen system created by an European group, and a new classification system proposed by the authors of this study. METHODS: A total of 56 patients with proximal humeral fractures were selected, and submitted to digitized simple radiography in antero-posterior shoulder and scapular profile. Radiographs were analyzed by three observers at time one, and then three and six weeks later. The kappa coefficient modified by Fleiss was used for the analysis. RESULTS: The mean intra-observer Kappa agreement index (k=0.687) of the new classification, was higher than both the Neer classification (k=0.362) and the Arbeit Gemeinschaft für Osteosynthesefragen (k=0.46). The mean interobserver Kappa agreement index (0.446) of the new classification, also had better results than both the Neer classification (k=0.063) and the Arbeit Gemeinschaft für Osteosynthesefragen (k=0.028). CONCLUSION: the new classification considering bone compression had higher results for intra- and interobserver compared to the Neer system, and the Arbeit Gemeinschaft für Osteosynthesefragen system.

OBJETIVO: Propor um novo sistema para classificação das fraturas que envolvem o colo do úmero e avaliar a concordância intra e interobservador do sistema de classificação de Neer (a mais utilizada em nosso meio), do sistema proposto pelo grupo europeu Arbeit Gemeinschaft für Osteosynthesefragen e de um novo sistema de classificação proposto pelos autores. MÉTODOS: Foram selecionados 56 pacientes com fraturas da região proximal do úmero, com radiografias simples digitalizadas nas incidências anteroposterior do ombro e perfil da escápula. Quatro observadores avaliaram as imagens radiográficas em três momentos diferentes, com intervalos de 3 semanas. Os dados foram analisados segundo o coeficiente de concordância kappa, modificado por Fleiss. RESULTADOS: O índice de concordância kappa intraobservador médio da nova classificação (k=0,687) foi superior ao da classificação de Neer (k=0,362) e da Arbeit Gemeinschaft für Osteosynthesefragen (k=0,46). O índice de concordância kappa interobservador da nova classificação (k=0,446) também apresentou um valor médio maior que o da classificação de Neer (k=0,063) e da Arbeit Gemeinschaft für Osteosynthesefragen (k=0,028). CONCLUSÃO: A nova classificação, que considera o conceito de compressão óssea, apresentou melhores resultados inter e intraobservador, em relação às classificações de Neer e Arbeit Gemeinschaft für Osteosynthesefragen.

Mineralization pattern of vertebral bone material following fragility fracture of the spine.

Little is known whether trabecular bone matrix mineralization is altered at the site of osteoporotic vertebral fractures. Bone mineralization density distribution (BMDD) was assessed in trabecular bone of acute, single-level compression fractures of the spine at various stages of fracture repair using quantitative backscattered electron imaging (qBEI). The grading of the repair stage was performed by histological methods. From 20 patients, who underwent either kyphoplasty (n=18) or vertebroplasty (n=2), a vertebral bone biopsy was taken prior to cement augmentation. Six patients took bisphosphonates (BP) prior to fracture. Three study groups were formed: N1=early-, N2=late-healing and B=BP treatment at late healing stage. In general, all groups had an altered BMDD when compared to historical normative reference data. Mean matrix mineralization (CaMean) was significantly (p<0.001) lower in all groups (N1: -5%, N2: -16%, and B2: -16%). In N2, CaMean was -13.1% (p<0.001) lower than N1. At this stage, deposition of new bone matrix and/or formation of woven bone are seen, which also explains the more heterogeneous matrix mineralization (CaWidth). Moreover, BP treatment (B2) led to a significant reduction in CaWidth (-28.5%, p<0.001), when compared to N2. Bone tissue from vertebrae with acute compression fractures reveals a large variation in matrix mineralization depending on the stage of repair. Bisphosphonate treatment does affect the mineralization pattern of tissue repair. The low mineralization values found in early stage of repair suggest that altered bone material properties may play a role in the occurrence of fragility fractures of the spine.

Fuzzy approach for reducing subjectivity in estimating occupational accident severity.

Quantifying or, more generally, estimating the severity of the possible consequences of occupational accidents is a decisive step in any occupational risk assessment process. Because of the lack of historic information (accident data collection and recording are incipient and insufficient, particularly in construction) and the lack of practical tools in the construction industry, the estimation/quantification of occupational accident severity is a notably arbitrary process rather than a systematic and rigorous assessment. This work proposes several severity functions (based on a safety risk assessment) to represent biomechanical knowledge with the aim of determining the severity level of occupational accidents in the construction industry and, consequently, improving occupational risk assessment quality. We follow a fuzzy approach because it makes it possible to capture and represent imprecise knowledge in a simple and understandable way for users and specialists.

Reproducibility of three classifications of proximal humeral fractures.

OBJECTIVE: To propose a new system for classifying proximal humeral neck fractures, and to evaluate intra- and interobserver agreement using the Neer system that is the most commonly used in the area and the Arbeit Gemeinschaft für Osteosynthesefragen system created by an European group, and a new classification system proposed by the authors of this study. METHODS: A total of 56 patients with proximal humeral fractures were selected, and submitted to digitized simple radiography in antero-posterior shoulder and scapular profile. Radiographs were analyzed by three observers at time one, and then three and six weeks later. The kappa coefficient modified by Fleiss was used for the analysis. RESULTS: The mean intra-observer Kappa agreement index (k = 0.687) of the new classification, was higher than both the Neer classification (k = 0.362) and the Arbeit Gemeinschaft für Osteosynthesefragen (k = 0.46). The mean interobserver Kappa agreement index (0.446) of the new classification, also had better results than both the Neer classification (k = 0.063) and the Arbeit Gemeinschaft für Osteosynthesefragen (k = 0.028). CONCLUSION: the new classification considering bone compression had higher results for intra- and interobserver compared to the Neer system, and the Arbeit Gemeinschaft für Osteosynthesefragen system.

OTA highlight paper predicting future displacement of nonoperatively managed lateral compression sacral fractures: can it be done?

PURPOSE: This study was designed to assess the rate of displacement in nondisplaced sacral fractures and to determine if certain fracture patterns are more prone to future displacement. DESIGN: Retrospective. SETTING: Two Level I trauma centers. PATIENTS: Patients consisted of those sustaining a lateral compression pelvic fracture whose age was 17 years or older, had less than 5 mm of initial sacral displacement, were the result of a high-energy mechanism, and had radiographs documenting bony union. INTERVENTION: By protocol, patients meeting these criteria were mobilized and maintenance of alignment was documented by serial radiographs. RESULTS: All fractures were classified according to the Orthopaedic Trauma Association classification system, the Young and Burgess mechanistic classification system, and to the location of the sacral fracture as described by Denis. In addition, sacral fractures were classified as complete or incomplete. Additionally, the number and location of rami fractures were recorded. Of the initial 117 fractures, 23 were determined to displace and largely consisted of a single fracture pattern. Fractures consisting of a complete sacral fracture combined with bilateral rami fractures displaced at a rate of 68% (15 of 22). In contrast, incomplete sacral fractures with an ipsilateral rami injury had no displaced unions. CONCLUSION: Incomplete lateral compression sacral fractures that are associated with ipsilateral rami fractures can be treated nonoperatively and are unlikely to displace. In contrast, those with a complete sacral fracture and bilateral rami fractures displace at a significantly greater rate.

Young-Burgess classification of pelvic ring fractures: does it predict mortality, transfusion requirements, and non-orthopaedic injuries?

OBJECTIVES: The objectives of this study were to evaluate the ability of the Young-Burgess classification system to predict mortality, transfusion requirements, and nonorthopaedic injuries in patients with pelvic ring fractures and to determine whether mortality rates after pelvic fractures have changed over time. DESIGN: Retrospective review. SETTING: Level I trauma center. PATIENTS: One thousand two hundred forty-eight patients with pelvic fractures during a 7-year period. INTERVENTION: None. MAIN OUTCOME MEASUREMENTS: Mortality at index admission, transfusion requirement during first 24 hours, and presence of nonorthopaedic injuries as a function of Young-Burgess pelvic classification type. Mortality compared with historic controls. RESULTS: Despite a relatively large sample size, the ability of the Young-Burgess system to predict mortality only approached statistical significance (P = 0.07, Kruskal-Wallis). The Young-Burgess system differentiated transfusion requirements--lateral compression Type 3 (LC3) and anteroposterior compression Types 2 (APC2) and 3 (APC3) fractures had higher transfusion requirements than did lateral compression Type 1 (LC1), anteroposterior compression Type 1 (APC1), and vertical shear (VS) (P < 0.05)--but was not as useful at predicting head, chest, or abdomen injuries. Dividing fractures into stable and unstable types allowed the system to predict mortality rates, abdomen injury rates, and transfusion requirements. Overall mortality in the study group was 9.1%, unchanged from original Young-Burgess studies 15 years previously (P = 0.3). CONCLUSIONS: The Young-Burgess system is useful for predicting transfusion requirements. For the system to predict mortality or nonorthopaedic injuries, fractures must be divided into stable (APC1, LC1) and unstable (APC2, APC3, LC2, LC3, VS, combined mechanism of injury) types. LC1 injuries are very common and not always benign (overall mortality rate, 8.2%).

Does 2.5 cm of symphyseal widening differentiate anteroposterior compression I from anteroposterior compression II pelvic ring injuries?

OBJECTIVE: It has been proposed that 2.5 cm of diastasis of the symphysis pubis corresponds with injury to the anterior sacroiliac ligament and differentiates Young-Burgess anteroposterior compression Type I and II pelvic ring injuries. We hypothesized that if a pelvis has greater than 2.5 cm of symphysis pubis diastasis, the anterior sacroiliac ligaments are disrupted and the pelvic floor has failed. METHODS: Pure torsional moment was applied to cadaveric human pelves with the hemipelvis either unconstrained (n = 10) or constrained to move only in the plane of rotation (n = 10). We recorded displacement of the symphysis pubis and sacroiliac joint and the applied torque that corresponded with failure of the anterior sacroiliac ligaments. RESULTS: Average symphysis pubis diastasis at the point of anterior sacroiliac ligament failure was 2.2 cm (n = 20; range, 1-4.5 cm); however, 80% of the values were outside the range of 2 to 3 cm. Symphysis pubis diastasis in male specimens averaged 2.5 cm and in female specimens, 1.8 cm (P = 0.06). The sacrospinous and sacrotuberous ligaments that make up the pelvic floor were not injured in unconstrained testing (zero of 10 specimens) but were at least attenuated in constrained testing (10 of 10 specimens), either simultaneously or after anterior sacroiliac ligament failure. CONCLUSIONS: We were not able to confirm 2.5 cm of symphysis pubis diastasis as a valid differentiation point between anteroposterior compression I and II injuries because significant morphologic variation seems to exist. Our data support that anterior sacroiliac ligament disruption is likely for displacement greater than 4.5 cm and unlikely for values less than 1.8 cm. Our study suggests that sacrospinous and sacrotuberous ligaments might not rupture at the same time as the anterior sacroiliac ligament.