The purpose of this study was to validate the photogrammetric measurement of the angle of trunk rotation in relation to the scoliometer instrument. Fifty-eight prominences from individuals with ages between 7 and 18 and with suspicion of spinal asymmetry (SA) were evaluated through the scoliometer and photogrammetry. The photographs were analyzed in the Digital Image-based Postural Assessment software. For statistical purposes, we used Pearson's correlation test (r), root mean square error, Bland-Altman graphical analysis, and receiver operating characteristic curve. The level of significance was P ≤ .05. Excellent correlation for the angle of trunk rotation was obtained between the scoliometer and photogrammetry, with a root mean square error of 3°. The Bland-Altman graphical analysis showed equally dispersed data with no participants outside the limits of agreement. The receiver operating characteristic curve evidenced that (1) the cutoff point for the identification of the presence of spinal asymmetry is 4°; (2) mild to moderate SA is between 4° and 7°; (3) moderate to severe SA is above 8°; and (4) sensitivity and specificity were above 83% and 78%, respectively, with an area under the curve ≥ 90%. Photogrammetry is validated for measuring the angle of trunk rotation, being an accurate and accessible tool for the evaluation of patients with spinal asymmetries.

This prospective study aimed to assess the concurrent validity and diagnostic accuracy of a mathematical procedure for measurement of the spinal inclination angle, analogous to the Cobb angle, by means of photogrammetry. Sixty-one subjects (aged 7 to 18 years), male and female, underwent radiographic (Cobb angle) and photogrammetric (DIPA [Digital Image-based Postural Assessment] angle) evaluations. The measurement of spinal inclination angle obtained through photogrammetry followed the Digital Image-Based Postural Assessment software protocol. Concurrent validity was appraised using Spearman rank correlation, the coefficient of determination, the root-mean-square error, Bland-Altman plot analysis, and receiver operating characteristic analysis, adopting P ≤ .05. The analyses were divided according to the topography of the scoliotic curve (thoracic, lumbar, or thoracolumbar). The correlations were excellent (from 0.72 to 0.81) and significant for all the regions of the spine, and the coefficients of determination ranged between 0.75 and 0.88. The root-mean-square error was between 5° and 11°, and the mean difference was very close to 0. The area under the curve was excellent and significant, ranging between 95% and 99%. The mathematical procedure presented is valid to evaluate the spinal inclination angle in photogrammetry, analogous to the Cobb angle in radiography.

The aim of this study was to present the development and assessment of the measurement accuracy of variables obtained with the Digital Imaged-based Postural Assessment (DIPA©) Capture app and Analysis software as part of a telehealth assessment protocol for idiopathic scoliosis. To enable the correct capture of photographic images for further analysis, the development of an application, called DIPA© Capture, was performed. A photo is automatically obtained only when the smartphone is aligned. The sample of this prospective study was composed of consecutive images of a real plumb line (RPL) taken by using the DIPA© Capture app. Once the photo was captured the app automatically drew a virtual plumb line (VPL). The inclination of the RPL and VPL was measured using the DIPA-S© eHealth Analysis software. A total of 50 images using the App comprised this sample. The median (min-max) inclination angle of the real and virtual plumb lines was 89.8° (88.6°-90°) with a 1.4° range and 90° (89.4°-90°) with a 0.6° range, respectively. The mean difference between the inclination of the two plumb lines (RPL - VPL) was very small -0.1°±0.04° (p= 0.017). The RMS error was 0.3°. The DIPA© Capture app and Analysis software for image acquisition and measurement was developed and is ready for testing with patients. The app accurately captures the alignment of the smartphone during the image acquisition and the software shows adequate measurement accuracy for future assessment of idiopathic scoliosis by photogrammetry. Level of Evidence III; Diagnostic Studies - Investigation of a Diagnostic Test.

Fotogrametria é um método de avaliação postural que fornece informações baseadas no referencial de marcadores anatômicos. No plano sagital, uma das principais avaliações está relacionada ao fio de prumo, apresentando divergências a respeito da colocação do marcador de referência maleolar na bibliografia. Alguns defendem que seja feita exatamente sobre o centro do maléolo lateral, enquanto outros defendem a colocação um pouco à frente do maléolo lateral. O objetivo deste estudo foi identificar se a modificação da posição do marcador maleolar influencia os resultados do procedimento. Trata-se de um estudo observacional analítico transversal, com delineamento comparativo intrassujeitos. Foram avaliados 44 indivíduos saudáveis (25 mulheres e 19 homens; 27±6 anos; 170±11cm; 71±15Kg) utilizando o protocolo e software DIPA^© para investigação das variáveis (teste do fio de prumo e pulsão da pelve) no plano sagital, com o marcador maleolar em duas posições: (1) no centro do maléolo lateral e (2) à frente do maléolo lateral. A análise realizada segundo os métodos estatístico, descritivo (distribuição de frequências, média e desvio padrão) e inferencial (testes de Shapiro Wilk, t de Student dependente e Wilcoxon, α=0,05). Para ambas as variáveis, a posição do marcador maleolar exerceu influência estatisticamente significativa (p0,05) a classificação postural. Os resultados sugerem que o ponto de referência vertical para a fotogrametria, baseado no marcador maleolar pode ser de escolha do avaliador.