RESUMEN
Abstract Objective: To describe the performance of a non-fluoroscopic fixed-flexion PA radiographic protocol with a new positioning device, developed for the assessment of knee osteoarthritis (OA) in Brazilian Longitudinal Study of Adult Health Musculoskeletal Study (ELSA-Brasil MSK). Material and methods: A test–retest design including 19 adults (38 knee images) was conducted. Feasibility of the radiographic protocol was assessed by image quality parameters and presence of radioanatomic alignment according to intermargin distance (IMD) values. Repeatability was assessed for IMD and joint space width (JSW) measured at three different locations. Results: Approximately 90% of knee images presented excellent quality. Frequencies of nearly perfect radioanatomic alignment (IMD ≤1 mm) ranged from 29% to 50%, and satisfactory alignment was found in up to 71% and 76% of the images (IMD ≤1.5 mm and ≤1.7 mm, respectively). Repeatability analyses yielded the following results: IMD [SD of mean difference = 1.08; coefficient of variation (%CV) = 54.68%; intraclass correlation coefficient (ICC) (95%CI) = 0.59 (0.34–0.77)]; JSW [SD of mean difference = 0.34–0.61; %CV = 4.48%–9.80%; ICC (95%CI) = 0.74 (0.55–0.85)–0.94 (0.87–0.97)]. Adequately reproducible measurements of IMD and JSW were found in 68% and 87% of the images, respectively. Conclusions: Despite the difficulty in achieving consistent radioanatomic alignment between subsequent radiographs in terms of IMD, the protocol produced highly repeatable JSW measurements when these were taken at midpoint and 10 mm from the medial extremity of the medial tibial plateau. Therefore, measurements of JSW at these locations can be considered adequate for the assessment of knee OA in ELSA-Brasil MSK.
Resumo Objetivo: Descrever o desempenho de um protocolo radiográfico em flexão fixa sem fluoroscopia em incidência PA com um novo posicionador, desenvolvido para a avaliação da osteoartrite de joelho (OA) no estudo ELSA-Brasil ME. Material e métodos: Fez-se um estudo de teste e reteste que incluiu 19 adultos (38 imagens de joelho). A viabilidade do protocolo radiográfico foi avaliada por meio de parâmetros de qualidade da imagem e presença de alinhamento radioanatômico de acordo com as medidas da distância intermarginal (DIM). Avaliaram-se a repetibilidade dos valores de DIM e do espaço articular (EA) em três locais diferentes. Resultados: Aproximadamente 90% das imagens de joelho apresentaram uma qualidade excelente. As frequências de imagens com alinhamento radioanatômico quase perfeito (DIM<1mm) variaram de 29% a 50%, e de alinhamento satisfatório (DIM<1,5mm e <1,7mm) de 71% a 76%, respectivamente. As análises de repetibilidade produziram os seguintes resultados: DIM [DP da média das diferenças = 1,08; coeficiente de variação (% CV) = 54,68%; coeficiente de correlação intraclasse (CCI) (IC 95%) = 0,59 (0,34 a 0,77)]; EA [DP da média das diferenças = 0,34 a 0,61; % CV = 4,48% a 9,80%; CCI (IC 95%) = 0,74 (0,55 a 0,85) a 0,94 (0,87 a 0,97]. Encontraram-se medidas adequadamente reprodutíveis de DIM e EA em 68% e 87% das imagens, respectivamente. Conclusões: Apesar da dificuldade de obter um alinhamento radioanatômico consistente entre radiografias repetidas em termos de DIM, o protocolo produziu medições de EA altamente repetíveis quando essas foram tomadas no ponto médio e a 10 mm da extremidade medial do platô tibial medial. Portanto, as medidas de EA nesses locais podem ser consideradas adequadas para a avaliação da OA de joelho no estudo ELSA-Brasil ME.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Osteoartritis de la Rodilla/diagnóstico por imagen , Posicionamiento del Paciente/instrumentación , Articulación de la Rodilla/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Brasil , Radiografía , Radiografía/instrumentación , Estudios de Factibilidad , Reproducibilidad de los Resultados , Estudios Longitudinales , Osteoartritis de la Rodilla/patología , Persona de Mediana EdadRESUMEN
OBJECTIVE: To describe the performance of a non-fluoroscopic fixed-flexion PA radiographic protocol with a new positioning device, developed for the assessment of knee osteoarthritis (OA) in Brazilian Longitudinal Study of Adult Health Musculoskeletal Study (ELSA-Brasil MSK). MATERIAL AND METHODS: A test-retest design including 19 adults (38 knee images) was conducted. Feasibility of the radiographic protocol was assessed by image quality parameters and presence of radioanatomic alignment according to intermargin distance (IMD) values. Repeatability was assessed for IMD and joint space width (JSW) measured at three different locations. RESULTS: Approximately 90% of knee images presented excellent quality. Frequencies of nearly perfect radioanatomic alignment (IMD ≤1mm) ranged from 29% to 50%, and satisfactory alignment was found in up to 71% and 76% of the images (IMD ≤1.5mm and ≤1.7mm, respectively). Repeatability analyses yielded the following results: IMD [SD of mean difference=1.08; coefficient of variation (%CV)=54.68%; intraclass correlation coefficient (ICC) (95%CI)=0.59 (0.34-0.77)]; JSW [SD of mean difference=0.34-0.61; %CV=4.48%-9.80%; ICC (95%CI)=0.74 (0.55-0.85)-0.94 (0.87-0.97)]. Adequately reproducible measurements of IMD and JSW were found in 68% and 87% of the images, respectively. CONCLUSIONS: Despite the difficulty in achieving consistent radioanatomic alignment between subsequent radiographs in terms of IMD, the protocol produced highly repeatable JSW measurements when these were taken at midpoint and 10mm from the medial extremity of the medial tibial plateau. Therefore, measurements of JSW at these locations can be considered adequate for the assessment of knee OA in ELSA-Brasil MSK.