ORAL PRESENTATION Open Access Analysis of anterior trunk symmetry index (ATSI). Preliminary report L Stolinski1*, T Kotwicki2, D Czaprowski1,2,3, J Chowanska1,2 From 9th International Conference on Conservative Management of Spinal Deformities - SOSORT 2012 Annual Meeting Milan, Italy. 10-12 May 2012 Background Spinal deformities and postural disorders can be assessed by evaluation of trunk surface deformity. Usually, the back shape is assessed. However, the ante- rior trunk can also develop deformity, which is observed by the patient more easily than the back surface. Aim of the study To introduce a new parameter, Anterior Trunk Symme- try Index (ATSI), for anterior trunk deformity assessment. Methods Seventy primary school children, free of idiopathic scolio- sis, both sexes, aged 6-7 years, mean 6.9 ± 0.3 years were examined with digital photography of their trunk, taken from the front in standardized conditions. The anatomi- cal landmarks were: sternal notch, acromions, axilla folds, waist lines, and umbilicus. ATSI was defined as the sum of six indices: three frontal plane asymmetry indices (one for sternal notch, axilla folds and waist lines, respec- tively) and three height difference indices, (one for acro- mions, axilla folds, and waist lines, respectively). The software was developed for semi-automatic calculation of ATSI, after the anatomical points are indicated on a digi- tal photo by the observer. The intra-observer error was calculated by the first author, by measuring four times the pictures of 20 children, in the interval of at least one day. The inter-observer error was calculated by one sur- geon, and three experienced physiotherapists, by measur- ing the pictures of 20 children. The normal value limit was calculated as mean ± 3SD. Results The assessment of the ATSI on digital photography took around 1 minute. The mean ATSI value for 70 children was 22.6 ± 10.8. The intra-observer error was 1.23. The inter-observer error for the four observers was 3.08. The normal value limit was 32.3. Conclusion This new surface parameter can be easily calculated on regular digital photographs of the anterior trunk. Both intra- and inter-observer errors are small, indicating possible reliability of ATSI for the assessment of ante- rior trunk asymmetry in children. Further studies are needed to assess the clinical usefulness of the ATSI parameter. Author details 1Rehasport Clinic, Poznan, Poland. 2Spine Disorders Unit, Department of Pediatric Orthopedics and Traumatology, University of Medical Sciences, Poznan, Poland. 3The Faculty of Physiotherapy, Jozef Rusiecki University, Olsztyn, Poland. Published: 3 June 2013 References 1. Suzuki N, I K, Ono T, Kohno K, Asher MA: Analysis of posterior trunk symmetry index (POTSI) in scoliosis, part 1. Stud Health Technol Inform 1999, 59:81-84. 2. Inami K, S N, Ono T, Yamashita Y, Kohno K, Morisue H: Analysis of posterior trunk symmetry index (POTSI) in scoliosis, part 2. Stud Health Technol Inform 1999, 59:85-88. 3. Minguez MF, Buendia M, Cibrian RM, Salvador R, Laguia M, Martin A, Gomar F: Quantifier variables of the back surface deformity obtained with a noninvasive structured light method: evaluation of their usefulness in idiopathic scoliosis diagnosis. Eur Spine J 2007, 16(1):73-82. doi:10.1186/1748-7161-8-S1-O25 Cite this article as: Stolinski et al.: Analysis of anterior trunk symmetry index (ATSI). Preliminary report. Scoliosis 2013 8(Suppl 1):O25. 1Rehasport Clinic, Poznan, Poland Full list of author information is available at the end of the article Stolinski et al. Scoliosis 2013, 8(Suppl 1):O25 http://www.scoliosisjournal.com/content/8/S1/O25 © 2013 Stolinski et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. http://www.ncbi.nlm.nih.gov/pubmed/16609858?dopt=Abstract http://www.ncbi.nlm.nih.gov/pubmed/16609858?dopt=Abstract http://www.ncbi.nlm.nih.gov/pubmed/16609858?dopt=Abstract http://creativecommons.org/licenses/by/2.0 Background Aim of the study Methods Results Conclusion Author details References