New classification for bone type at dental implant sites: a dental computed tomography study.

OBJECTIVE: This study proposed a new classification method of bone quantity and quality at the dental implant site using cone-beam computed tomography (CBCT) image analysis, classifying cortical and cancellous bones separately and using CBCT for quantitative analysis. METHODS: Preoperative CBCT images were obtained from 128 implant patients (315 sites). First, measure the crestal cortical bone thickness (in mm) and the cancellous bone density [in grayscale values (GV) and bone mineral density (g/cm3)] at the implant sites. The new classification for bone quality at the implant site proposed in this study is a "nine-square division" bone classification system, where the cortical bone thickness is classified into A: > 1.1 mm, B:0.7-1.1 mm, and C: < 0.7 mm, and the cancellous bone density is classified into 1: > 600 GV (= 420 g/cm3), 2:300-600 GV (= 160 g/cm3-420 g/cm3), and 3: < 300 GV (= 160 g/cm3). RESULTS: The results of the nine bone type proportions based on the new jawbone classification were as follows: A1 (8.57%,27/315), A2 (13.02%), A3 (4.13%), B1 (17.78%), B2 (20.63%), B3 (8.57%) C1 (4.44%), C2 (14.29%), and C3 (8.57%). CONCLUSIONS: The proposed classification can complement the parts overlooked in previous bone classification methods (bone types A3 and C1). TRIAL REGISTRATION: The retrospective registration of this study was approved by the Institutional Review Board of China Medical University Hospital, No. CMUH 108-REC2-181.

INTRA- AND INTER-OBSERVER AGREEMENT OF PROXIMAL HUMERAL FRACTURES CLASSIFICATIONS IN ADULTS.

Objective: Evaluating intra- and inter-observer agreement of the Neer, AO, and AO/OTA proximal humerus fractures classification systems in adults. Methods: In total, 100 X-rays of patients with proximal humerus fractures were selected according to the inclusion and exclusion criteria established in this study. They were evaluated by four evaluators with different levels of expertise. The evaluation was performed at two distinct moments, with an interval of 21 days between each analysis. Images were randomized for the second evaluation by a researcher who did not participate in the image selection process. A Fleiss Kappa test was performed to evaluate intra- and inter-observer agreement. Results: We observed a substantial agreement with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classification systems, respectively. Conclusion: In the second evaluation, intra-observer agreement improved. In the first evaluation, we obtained values of k = 0.724, k = 0.490, and k = 0.599 for the evaluation of the Neer, AO, and AO/OTA classifications. In the second evaluation, the values k = 0.759, k = 0.772, and k = 0.858. Therefore, the evaluations went from moderate to substantial for the AO classification and from moderate to practically perfect for the AO/OTA classification. The level of inter-observer agreement was substantial (0.61-0.80), with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classifications, respectively. Level of Evidence III, Cross-Sectional Observational Study.

Objetivo: Avaliar a concordância intra e interobservadores entre os sistemas de classificação Neer, AO e AO/OTA nas fraturas do úmero proximal de indivíduos adultos. Métodos: Após a aplicação dos critérios de inclusão e exclusão determinados para a realização deste trabalho, foram selecionadas 100 radiografias de pacientes com fratura do úmero proximal. Estas foram submetidas à avaliação de quatro examinadores com níveis diferentes de expertise. A avaliação foi realizada em dois momentos distintos, com intervalo de 21 dias entre cada análise. As imagens foram randomizadas para a segunda avaliação por um pesquisador que não participou da seleção de imagens. Foi aplicado o teste kappa de Fleiss para verificar a concordância intra e interobservador. Resultados: Na primeira avaliação obtivemos valores de k = 0,724, k = 0,490 e k = 0,599, enquanto na segunda avaliação, os valores k = 0,759, k = 0,772 e k = 0,858 para as avaliações de Neer, AO e AO/OTA, respectivamente. Isso indica que a concordância intraobservador melhorou na segunda avaliação. Conclusões: As avaliações passaram de moderada para substancial para a classificação AO e de moderada para praticamente perfeita para o sistema AO/OTA. O nível de concordância interobservadores foram considerados substanciais (0,61-0,80) com k = 0,669, k = 0,715 e k = 0,780 para as classificações de Neer, AO e AO/OTA, respectivamente. Nível de Evidência III, Estudo Transversal Observacional.

Multi-center Retrospective Study of Factors Affecting Perioperative Transfusion of Packed Red Blood Cells for Pelvic Fracture Patients.

OBJECTIVE: To analyze the use of packed red blood cells (PRBCs) for patients with pelvic fracture and evaluate factors associated with PRBC transfusion for patients with pelvic fracture. METHODS: This retrospective cohort study collected 551 patients with pelvic fractures from six hospitals between September 1, 2012, and June 31, 2019. The age span of patients varied from 10 to 95 years old, and they were classified into two groups based on high-energy pelvic fractures (HE-PFs) or low-energy pelvic fractures (LE-PFs). The study's outcome was the use of PRBCs, fresh frozen plasma (FFP), and albumin. Demographic data, characteristics, laboratory tests, clinical treatment details, and clinical outcomes were compared between the two groups. Factors that were statistically associated with perioperative PRBCs in univariate analyses were included to conduct an optimal scale regression to determine the independent factors for perioperative PRBCs. RESULTS: A total of 551 patients were screened from six hospitals, and after inclusion and exclusion, 319 were finally included and finished the follow-up from admission to discharge, while four patients died during hospitalization. Three hundred and nineteen patients were classified into two groups by their injury mechanisms. A total of 230/319 (72.1%) patients were classified into the HE-PF group, and 89/319 (27.8%) patients were classified into the LE-PF group. Patients in the HE-PF group were transfused with 4.5 (3-8) units of PRBCs, 300 (0-600) ml of FFP, and 0 (0-30) g of albumin, while patients in the LE-PF group were transfused with 3.5 (2-4.5) units of PRBCs, 0 (0-295) ml of FFP, and 0 (0-0) g of albumin (all P < 0.001). There were higher proportions of male patients and patients under 65 in the HE-PF group (all P < 0.001). HE-PF group patients were more severely injured and likely to take external fixation. The optimal scale regression revealed four significant factors associated with perioperative transfused PRBCs, which were patients on admission with hemorrhagic shock (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.148, P = 0.039), and methods of pelvic fixation (importance = 0.008, P = 0.026), ranked by the importance. CONCLUSION: Patients with HE-PFs had increased transfusions of PRBCs, FFP, and albumin, and hemorrhagic shock on admission, Tile classification, Hb levels, and stabilization methods were found to be associated with perioperative PRBCs.

Intra- and inter-observer agreement of proximal humeral fractures classifications in adults / Concordância intra e interobservadores das classificações nas fraturas do úmero proximal em adultos

ABSTRACT Objective: Evaluating intra- and inter-observer agreement of the Neer, AO, and AO/OTA proximal humerus fractures classification systems in adults. Methods: In total, 100 X-rays of patients with proximal humerus fractures were selected according to the inclusion and exclusion criteria established in this study. They were evaluated by four evaluators with different levels of expertise. The evaluation was performed at two distinct moments, with an interval of 21 days between each analysis. Images were randomized for the second evaluation by a researcher who did not participate in the image selection process. A Fleiss Kappa test was performed to evaluate intra- and inter-observer agreement. Results: We observed a substantial agreement with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classification systems, respectively. Conclusion: In the second evaluation, intra-observer agreement improved. In the first evaluation, we obtained values of k = 0.724, k = 0.490, and k = 0.599 for the evaluation of the Neer, AO, and AO/OTA classifications. In the second evaluation, the values k = 0.759, k = 0.772, and k = 0.858. Therefore, the evaluations went from moderate to substantial for the AO classification and from moderate to practically perfect for the AO/OTA classification. The level of inter-observer agreement was substantial (0.61-0.80), with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classifications, respectively. Level of Evidence III, Cross-Sectional Observational Study.

RESUMO Objetivo: Avaliar a concordância intra e interobservadores entre os sistemas de classificação Neer, AO e AO/OTA nas fraturas do úmero proximal de indivíduos adultos. Métodos: Após a aplicação dos critérios de inclusão e exclusão determinados para a realização deste trabalho, foram selecionadas 100 radiografias de pacientes com fratura do úmero proximal. Estas foram submetidas à avaliação de quatro examinadores com níveis diferentes de expertise. A avaliação foi realizada em dois momentos distintos, com intervalo de 21 dias entre cada análise. As imagens foram randomizadas para a segunda avaliação por um pesquisador que não participou da seleção de imagens. Foi aplicado o teste kappa de Fleiss para verificar a concordância intra e interobservador. Resultados: Na primeira avaliação obtivemos valores de k = 0,724, k = 0,490 e k = 0,599, enquanto na segunda avaliação, os valores k = 0,759, k = 0,772 e k = 0,858 para as avaliações de Neer, AO e AO/OTA, respectivamente. Isso indica que a concordância intraobservador melhorou na segunda avaliação. Conclusões: As avaliações passaram de moderada para substancial para a classificação AO e de moderada para praticamente perfeita para o sistema AO/OTA. O nível de concordância interobservadores foram considerados substanciais (0,61-0,80) com k = 0,669, k = 0,715 e k = 0,780 para as classificações de Neer, AO e AO/OTA, respectivamente. Nível de Evidência III, Estudo Transversal Observacional.

The normal stiffness of the edentulous alveolar process.

The normal stiffness of the jawbone is seldom considered, as opposed to the mechanical properties of its individual cortical and trabecular components. Our standpoint is essentially structural, rather than purely material-oriented, as the jawbone is considered as a natural load-bearing structure. Throughout the work, 3 representative sections in the mandible and the maxilla are modelled and compared. Specifically, we evaluate the sections' elastic structural stiffness numerically, according to the recent geometrical classification proposed by Shemtov Yona (2021). Each case is modelled using two extreme configurations for the cortical-trabecular interaction, namely bonded and unbonded. Those two configurations reflect extreme interfacial conditions, though the bonded one is more physical. For the unbonded cases, the structural stiffness is the sum of the individual stiffnesses of the components. By sharp contrast, the bonded case results in a much larger stiffness than that obtained by the simple sum of the individual stiffnesses, indicating a strong synergistic stiffening effect between the components through their interface. We also investigate the role of the elastic moduli, whose reported values vary widely in the literature, emphasizing the role of the trabecular Poisson's coefficient, whose stiffening effect is evidenced when it exceeds about 0.3. The bone's structural stiffness shown here complements the geometrical classification of the jawbone types with a fundamental mechanical/structural property delineating the coupling between the mechanical properties and the geometry. The adopted approach is not limited to the jawbone and applies in principle to other bone types. From a clinical standpoint, the results presented here complement not only the basic mechanical aspects of the geometrical characterization, but also provide a starting point for future studies on dental implant placement and stability, the latter being directly related to the structural stiffness.

Interobserver reproducibility assessment of the new aospine classification for subaxial cervical lesions / Avaliação da reprodutibilidade interobservadores da nova classificação aospine para lesões cervicais subaxiais / Evaluación de la reproducibilidad interobservadores de la nueva clasificación aospine para lesiones cervicales subaxiales

ABSTRACT Objective: To evaluate the interobserver agreement of the new AOSpine classification for subaxial cervical fractures. Methods: A descriptive study, which11 traumatic lesions of the subaxial cervical spine (through radiographic and tomographic images), were evaluated by 16 observers being: 6 senior surgeons, 4 fellows in spinal surgery and 6 physicians residents in Orthopedics and Traumatology by the new AOSpine classification, with subsequent statistical analysis of the results. An agreement analysis was performed using the Kappa coefficient, both individually and in combination, with an interpretation of the index performed using the standardized model for Landis and Koch. To determine the level of significance of the analyzes, values less than 0.05 were considered statistically significant. Results: In general, the level of agreement among the examiners was considered reasonable. The lesions "A0 (F3)", "A4 (F3)", "B1", "B3", "B3 (F3)", "C", "C (F3)" and "F3"showed a low level of agreement between the examiners. The level of reasonable agreement was obtained between fractures "A0", "A1", "A4", "B2" and "C (F4)". The only fracture that presented a moderate level of agreement was the "C (F4 BL)" lesion. This result indicates that the referred injury was the fracture of the subaxial column that presented the best level of agreement among the 16 examiners in the present study. Conclusions: The results of the study indicate an intermediate agreement of the new AOSpine classification for subaxial cervical lesion and point to the need to carry out studies that seek to evaluate this new classification in order to better evaluate its strengths and weaknesses, contributing for its improvement. Level of evidence III; Diagnostic study - investigation of a diagnostic test.

RESUMO Objetivo: Avaliar a concordância interobservadores da nova classificação AOSpine para fraturas cervicais subaxiais. Métodos: Estudo descritivo, por meio do qual foram avaliadas 11 lesões traumáticas da coluna cervical subaxial (através de imagens radiográficas e tomográficas) por 16 observadores, sendo seis cirurgiões seniors, quatro fellows em cirurgia da coluna e seis médicos residentes em Ortopedia e Traumatologia, pela nova classificação AOSpine. A análise de concordância foi realizada através da do uso do coeficiente Kappa, tanto de forma individual como de forma combinada, sendo a interpretação do índice realizada através do modelo padronizado por Landis e Koch. Para determinar o nível de significância das análises, valores de p menores que 0.05 foram considerados estatisticamente significativos. Resultados: De maneira geral, o nível de concordância entre os examinadores foi considerado razoável. As lesões "A0(F3)", "A4(F3)", "B1", "B3", "B3(F3)", "C", "C(F3)" e "F3 apresentaram nível de concordância fraco entre os examinadores. O nível de concordância razoável foi obtido entre as fraturas "A0", "A1", "A4", "B2" e "C(F4)". A única fratura que apresentou nível de concordância moderado foi a lesão "C (F4 BL)". Esse resultado indica que a referida lesão foi a fratura da coluna subaxial que apresentou o melhor nível de concordância entre os 16 examinadores do presente estudo. Conclusões: Os resultados do estudo indicam uma concordância intermediária da nova classificação AOSpine para lesões da cervical subaxial e apontam para a necessidade da realização de estudos que busquem avaliar esta nova classificação, de forma a melhor avaliar seus pontos fortes e fracos, contribuindo para sua aprimoração. Nível de evidência III; Estudo diagnóstico- investigação de um exame para diagnóstico.

RESUMEN Objetivo: Evaluar la concordancia interobservadores de la nueva clasificación AOSpine para fracturas cervicales subaxiales. Métodos: Estudio descriptivo, a través del cual se evaluaron 11 lesiones traumáticas de la columna cervical subaxial (a través de imágenes radiográficas y tomográficas) por 16 observadores sendo: 6 cirujanos experimentados, 4 compañeros en cirugía de columna y 6 médicos residentes en Ortopedia y Traumatología por la nueva clasificación AOSpine. Se realizó un análisis de acuerdo utilizando el coeficiente Kappa, tanto individualmente como en combinación, con una interpretación del índice realizada utilizando el modelo estandarizado para Landis y Koch. Para determinar el nivel de significación de los análisis, se consideraron estadísticamente valores inferiores a 0,05. Resultados: En general, el nivel de concordancia entre los examinadores se consideró razonable. Las lesiones "A0 (F3)", "A4 (F3)", "B1", "B3", "B3 (F3)", "C", "C (F3)" y "F3 presentaron un nivel de concordancia débil entre los examinadores. El nivel de concordancia razonable se obtuvo entre las fracturas A0, A1, A4, B2 y C (F4). La única fractura que presentó un nivel de concordancia moderado fue la lesión "C (F4 BL)". Este resultado indica que dicha lesión fue la fractura de la columna subaxial que presentó el mejor nivel de concordancia entre los 16 examinadores del presente estudio. Conclusiones: Los resultados del estudio indican un acuerdo intermedio de la nueva clasificación de AOSpine para lesiones cervicales subaxiales y apuntan a la necesidad de realizar estudios que busquen evaluar esta nueva clasificación, para evaluar mejor sus puntos fuertes y débil, para su mejoramiento. Nivel de evidencia III; Estudio de diagnóstico: investigación de una prueba de diagnóstico.

The Influence of Tactile Perception on Classification of Bone Tissue at Dental Implant Insertion.

BACKGROUND: Various ways of using the Lekholm and Zarb (L&Z) classification have added to the lack of scientific evidence of the effectiveness of this clinical method in the evaluation of implant treatment. PURPOSE: The study aims to assess subjective jawbone classifications in patients referred for implant treatment, using L&Z classification with and without surgeon's hand perception at implant insertion. The association between bone type classifications and quantitative parameters of primary implant stability was also assessed. MATERIALS AND METHODS: One hundred thirty-five implants were inserted using conventional loading protocol. Three surgeons classified bone quality at implant sites using two methods: one based on periapical and panoramic images (modified L&Z) and one based on the same images associated with the surgeon's tactile perception during drilling (original L&Z). Peak insertion torque and implant stability quotient (ISQ) were recorded. RESULTS: The modified and original L&Z were strongly correlated (rho = 0.79; p < .001); Wilcoxon signed-rank test showed no significant difference in the distribution of bone type classification between pairs using the two methods (p = .538). Spearman correlation tested the association between primary stability parameters and bone type classifications (-0.34 to -0.57 [p < .001]). CONCLUSIONS: Tactile surgical perception has a minor influence on rating of subjective bone type for dental implant treatment using the L&Z classification.

Fractures of the neck of the talus: evaluation of reproducibility of Hawkins' classification.

OBJECTIVE: To evaluate the intraobserver and interobserver reproducibility of Hawkins' classification for fractures of the neck of the talus. METHODS: 20 random cases of fracture of the talus were selected, to be defined according to the classification of types by eight orthopedic surgeons, 13 orthopedic residents and 15 radiology residents. RESULTS: Using the statistical test of Landis and Koch, measurements of 0.627 and 0.668 were obtained in the first and second evaluations, respectively. These values define a satisfactory agreement for Hawkins' classification. CONCLUSION: We conclude that this classification is reproducible between observers, with better values for the more experienced observers. Level of Evidence I, Study Diagnostic - Investigating a diagnostic test.