Observer reliability between juvenile and adolescent idiopathic scoliosis in measurement of stable Cobb’s angle

Abstract

It is a measurement of Cobb's angles between adolescent (AIS) and juvenile (JIS) idiopathic scoliosis who had stable curves (variation <5 degrees) in more than three visits. Main objective of this paper is to measure inter- and intra-observer reliability of measurements between AIS and JIS who had stable curves in regular follow-up. Twenty-nine JIS and 44 AIS patients who had stable curves without bracing were identified using PACS system. Two observers independently measured Cobb's angle twice on first, during follow-up and final radiogram using computer-based digital radiogram. Both observers were given pre-decided level of upper and lower end plates. Inter- and intra-observer reliability of the measurement was calculated using Pearson correlation-coefficient test between JIS and AIS group. There was no significant difference in Cobb's angle in all measurements by both observers either in JIS (p = 0.756, range 0.706-0.815; ANOVA) or AIS (p = 0.871, range 0.795-0.929; ANOVA) group which suggested that there is no significant difference in Cobb's angle in repeated measurements. Intra-observer reliability for JIS (r = 0.600, range 0.521-0.751; Pearson test) was less than AIS (r = 0.969, range 0.943-0.984; Pearson test); and similarly, inter-observer reliability for JIS (r = 0.547, Pearson test) was also less than AIS (r = 0.961, Pearson test) which indicates that Cobb's angle measurement is less reliable in patients who have juvenile idiopathic scoliosis. Using the identical condition for measurements in both the groups, we could find only one reason for less reliability in JIS group and that is poor demarcation of the vertebral end-plates in this group. This poor inter- and intra-observer reliability in JIS due to ill-defined endplates can be reduced by measuring all previous curves along with latest curves at the same time during the follow-up of patients with JIS to decide about the progression of curves and treatment options.

Reprodutibilidade intra e interobservadores no ângulo de cobb em indivíduos escolióticos

“…A reprodutibilidade do ângulo de Cobb em escolióticos idiopáticos (juvenil e adolescente) foi, igualmente, medida mais recentemente por Modi et al 18 . Neste estudo, não houve diferenças significativas em todas as mensurações para ambos os observadores na escoliose idiopática juvenil (anova com variação de 0,706 a 0,815 e p = 0,756) e na escoliose idiopática do adolescente (anova com variação de 0,795 a 0,929 e p = 0,871).…”

“…Sabe-se que mensurações padronizadas do ângulo de Cobb, vinculadas ao controle de possíveis fontes de erro (intrínseco e extrínse-co) de medida, proporcionariam maior segurança quanto à efetividade do diagnóstico e, consequentemente, à conduta terapêutica 18 . Os problemas nas mensurações foram atribuídos às constantes trocas de instrumentos durante as mensurações e a não pré-seleção das vérte-bras.…”

“…Não houve correlação com a experiência prévia dos observadores. Por outro lado, as principais fontes de erro extrínseco mantiveram relação com a posição do paciente, a posição e distância do tubo durante o exame de raiox e com a hora na realização do exame 13,18 .…”

Reliability and validity of rasterstereography measurement for spinal alignment in healthy subjects

“…Cobb's angle is an objective method of spinal deformity in which it is the angle formed between a line drawn parallel to the superior endplate of one vertebrae above the fracture and a line drawn parallel to the inferior endplate of the vertebrae one level below the fracture [12]. X-rays of C1 to the coccyx were taken in the frontal plane.…”

Redução da dor crônica associada à escoliose não estrutural, em universitárias submetidas ao método Pilates

“…No exame da imagem radiográfica, a fisioterapeuta além de confirmar a escoliose observada na inspeção anterior mediu o ângulo de Cobb, que foi obtido pelo traço de uma linha paralela à borda superior da vértebra limítrofe superior e outra na borda inferior da vértebra limítrofe inferior da escoliose. A intersecção destas duas linhas determinou a angulação do desvio da coluna vertebral (MODI et al, 2008). Este ângulo foi medido com um goniômetro da marca CARCI (Brasil).…”