Knee MR Using a Body Coil is Equivalent to CT in Measuring the TT-TG Distance: Removing the Systematic Bias.

Objective To compare magnetic resonance imaging (MRI) using a body coil with computed tomography (CT) in measuring the tibial tubercle-trochlear groove distance (TT-TG) and the patellar tendon-cartilaginous trochlear groove (PT-CTG) distances, and evaluate interrater reliability. Methods The study group consisted of 34 knees from 17 asymptomatic subjects with no history of knee pathology, trauma or surgery. A low-dose CT scan and an axial T1-weighted MRI sequence of the knees were performed with rigorous standardization of the positioning with full extension of the knees and parallel feet. Two musculoskeletal radiologists performed the measurements independently. The reliability of the TT-TG and PT-CTG distances on CT (17.1 ± 4.2 mm and 17.3 ± 4.2 mm) and of MRI (16.2 ± 3.7 mm and 16.5 ± 4.1 mm) was assessed by intraclass correlation coefficient (ICC [2,1]) and Bland-Altman graphs, as well as the interrater reliability for both methods. Results Good reliability and agreement was observed between CT and MRI measurements for TT-TG and PT-CTG, with an ICC of 0.774 ( p < 0.001) and 0.743 ( p < 0.001), respectively, and no systematic bias was observed. The interrater reliability was excellent for all measurements on both imaging methods. Conclusion This was the first study that compared MRI using a body coil with CT in measuring the TT-TG distance, with the potential clinical implication that the CT in this clinical setting could be avoided.

Knee MR Using a Body Coil is Equivalent to CT in Measuring the TT-TG Distance: Removing the Systematic Bias / A ressonância magnética do joelho usando a bobina de corpo é equivalente à TC na medição da distância TT-ST: Removendo o viés sistemático

Abstract Objective To compare magnetic resonance imaging (MRI) using a body coil with computed tomography (CT) in measuring the tibial tubercle-trochlear groove distance (TT-TG) and the patellar tendon-cartilaginous trochlear groove (PT-CTG) distances, and evaluate interrater reliability. Methods The study group consisted of 34 knees from 17 asymptomatic subjects with no history of knee pathology, trauma or surgery. A low-dose CT scan and an axial T1-weighted MRI sequence of the knees were performed with rigorous standardization of the positioning with full extension of the knees and parallel feet. Two musculoskeletal radiologists performed the measurements independently. The reliability of the TT-TG and PT-CTG distances on CT (17.1 ± 4.2 mm and 17.3 ± 4.2 mm) and of MRI (16.2 ± 3.7 mm and 16.5 ± 4.1 mm) was assessed by intraclass correlation coefficient (ICC [2,1]) and Bland-Altman graphs, as well as the interrater reliability for both methods. Results Good reliability and agreement was observed between CT and MRI measurements for TT-TG and PT-CTG, with an ICC of 0.774 (p< 0.001) and 0.743 (p< 0.001), respectively, and no systematic bias was observed. The interrater reliability was excellent for all measurements on both imaging methods. Conclusion This was the first study that compared MRI using a body coil with CT in measuring the TT-TG distance, with the potential clinical implication that the CT in this clinical setting could be avoided.

Resumo Objetivo Comparar a ressonância magnética (RM) usando uma bobina corporal e tomografia computadorizada (TC) na medição da distância tubérculo tibial-sulco troclear (TT-ST) e as distâncias tendão patelar-sulco troclear cartilaginoso (TP-STC), e avaliar a confiabilidade interavaliador. Métodos O grupo de estudo consistiu em 34 joelhos de 17 indivíduos assintomáticos sem história de patologia, trauma ou cirurgia no joelho. Uma tomografia computadorizada (TC) de baixa dose e uma sequência axial de RM ponderada em T1 dos joelhos foram realizadas com padronização rigorosa do posicionamento com extensão total dos joelhos e pés paralelos. Dois radiologistas musculoesqueléticos realizaram as medidas de forma independente. A confiabilidade das distâncias TT-ST e TP-STC na TC (17,1 ± 4,2 mm e 17,3 ± 4,2 mm) e RM (16,2 ± 3,7 mm e 16,5 ± 4,1 mm), foi avaliada pelo coeficiente de correlação intraclasse (CCI [2,1)]) e gráficos Bland-Altman, bem como a confiabilidade entre avaliadores para ambos os métodos. Resultados Boa confiabilidade e concordância foram observadas entre as medidas de TC e RM para TT-ST e TP-STC com um CCI de 0,774 (p< 0,001) e 0,743 (p< 0,001), respectivamente, e nenhum viés sistemático foi observado. A confiabilidade entre avaliadores foi excelente para todas as medições em ambos os métodos de imagem. Conclusão Este foi o primeiro estudo que comparou a RM usando bobina de corpo com a TC na medição da distância TT-ST, com a implicação clínica potencial de que a TC neste cenário clínico poderia ser evitada.

Analysis of the reliability of the lee classification for lumbar disc herniations / Análise da confiabilidade da classificação de lee para hérnias de discos lombares / Análisis de la confiabilidad de la clasificación de lee para hernias de discos lumbares

ABSTRACT Objective To evaluate the intra- and interobserver reliability of the Lee et al. classification for migrated lumbar disc herniations. Methods In 2018, Ahn Y. et al. demonstrated the accuracy of this classification for radiologists. However, magnetic resonance images are often interpreted by orthopedists. Thus, a cross-sectional study was conducted by evaluating the magnetic resonance images of 82 patients diagnosed with lumbar disc herniation. The images were evaluated by 4 physicians, 3 of whom were spinal orthopedic specialists and 1 of whom was a radiologist. The intra- and interobserver analysis was conducted using the percentage of concordance and the Kappa method. Results The report of the classifications used by the four observers had a higher proportion of "zone 3" and "zone 4" type classifications in both evaluation moments. The most affected anatomical levels were L5-S1 (48.2%) and L4-L5 (41.4%). The intra- and interobserver concordance, when comparing both moments evaluation of the complementary examinations of the participants involved, was classified as moderate and very good. Conclusions Lee's classification presented moderate to very good intra- and interobserver reliability for the evaluation of migrated lumbar disc herniation. Level of evidence II; Retrospective Study.

RESUMO Objetivo Avaliar a confiabilidade intra e interobservador da classificação de Lee et al. para hérnias migradas de disco lombar. Métodos Ahn Y et al., em 2018, demonstraram a acurácia dessa classificação para radiologistas. Entretanto, as imagens de ressonância magnética são muitas vezes interpretadas por ortopedistas. Sendo assim, foi realizado um estudo transversal por meio da avaliação de exames de ressonância magnética de 82 casos diagnosticados com hérnia de disco lombar. As imagens foram avaliadas por quatro médicos, sendo três ortopedistas especialistas em cirurgia da coluna e um radiologista. Foi realizada a análise de confiabilidade intra e interobservador com o uso de porcentagem de concordância e do método Kappa. Resultados A relação das classificações utilizadas pelos quatro avaliadores tiveram, em sua maior proporção, as classificações tipo "zona 3" e "zona 4" em ambos os momentos de avaliação. Os níveis anatômicos mais acometidos foram L5-S1 (48,8%) e L4-L5 (41,4%). A concordância intra e interobservador, que comparou os dois momentos de avaliação dos exames complementares dos participantes envolvidos, obteve classificações de moderada a muito boa. Conclusões A classificação de Lee apresentou confiabilidade intra e interobservador moderada a muito boa para a avaliação de hérnia migrada de disco lombar. Nível de evidência II; Estudo Retrospectivo.

RESUMEN Objetivo Evaluar la confiabilidad intra e interobservador de la clasificación de Lee et al. para hernias migradas de disco lumbar. Métodos Ahn Y et al. en 2018, demostraron la exactitud de esa clasificación para los radiólogos. Entretanto, las imágenes de resonancia magnética son a menudo interpretadas por ortopedistas. Siendo así, fue realizado un estudio transversal a través de la evaluación de exámenes de resonancia magnética de 82 casos diagnosticados con hernia de disco lumbar. Las imágenes fueron evaluadas por cuatro médicos, siendo tres ortopedistas especialistas en cirugía de la columna y un radiólogo. Se realizó el análisis de confiabilidad intra e interobservador con el uso de porcentaje de concordancia y Método Kappa. Resultados La relación de las clasificaciones utilizadas por los cuatro evaluadores tuvieron, en su mayor proporción, las clasificaciones tipo "zona 3" y "zona 4" en ambos momentos de evaluación. Los niveles anatómicos más acometidos fueron L5-S1 (48,8%) y L4-L5 (41,4%). La concordancia intra e interobservador, que comparó los dos momentos de evaluación de los exámenes complementarios de los participantes involucrados, obtuvo clasificaciones de moderada a muy buena. Conclusiones La clasificación de Lee presentó confiabilidad intra e interobservador moderada a muy buena para la evaluación de hernia migrada discal lumbar. Nivel de evidencia II; Estudio Retrospectivo.

Should the meniscal height be considered for preoperative sizing in meniscal transplantation?

PURPOSE AND HYPOTHESIS: In preoperative sizing for meniscal transplantation, most authors take into consideration the length and width of the original meniscus, but not its height. This study aimed at evaluating (1) whether the meniscal height is associated with the meniscal length and width, (2) whether the heights of the meniscal segments are associated with the individual's anthropometric data, (3) whether the heights of the meniscal segments are associated with each other in the same meniscus, and (4) the degree of symmetry of the meniscal dimensions between the right and left knees. METHODS: In this cross-sectional, observational study, two independent radiologists measured the meniscal length, width and height in knee magnetic resonance imaging scans obtained from 25 patients with patello-femoral pain syndrome. Reproducibility of measurements was calculated with intraclass correlation coefficients. Associations between the anthropometric data and the meniscal measurements, the meniscal length and width versus height, and the heights of the meniscal segments in the same meniscus were examined with Pearson's correlation. RESULTS: Inter-observer reliability was excellent (>0.8) for length and height and good (0.6-0.8) for width measurements. There was also excellent agreement (>0.8) for the length and width of the menisci in the right and left knees. The heights of the horns of the lateral meniscus showed good agreement (0.6-0.8), while the heights of the other meniscal segments had excellent agreement between the sides (>0.8). There were significant associations with generally low (r < 0.5) correlation between the heights of the meniscal segments and the lengths and widths of the menisci, between the meniscal height and anthropometric data, and between the heights of the meniscal segments in the same meniscus. Correlations between anthropometric data and meniscal length and width were generally high (r > 0.7). CONCLUSIONS: There was excellent agreement between the meniscal dimensions of the right and left knees, and a weak association between the meniscal height with the meniscal width and length, between the height of the menisci with anthropometric data and between the heights of the segments in the same meniscus. The height of the meniscal segments may be a new variable in preoperative meniscal measurement.