Use of the smartphone for end vertebra selection in scoliosis

Abstract

Objectives: The aim of our study was to develop a smartphone-aided end vertebra selection method andto investigate its effectiveness in Cobb angle measurement.Methods: Twenty-nine adolescent idiopathic scoliosis patients' pre-operative posteroanterior scoliosisradiographs were used for end vertebra selection and Cobb angle measurement by standard method andsmartphone-aided method. Measurements were performed by 7 examiners. The intraclass correlationcoefŞcient was used to analyze selection and measurement reliability. Summary statistics of variancecalculations were used to provide 95% prediction limits for the error in Cobb angle measurements. Apaired 2-tailed t test was used to analyze end vertebra selection differences.Results: Mean absolute Cobb angle difference was 3.6for the manual method and 1.9for thesmartphone-aided method. Both intraobserver and interobserver reliability were found excellent inmanual and smartphone set for Cobb angle measurement. Both intraobserver and interobserver reliability were found excellent in manual and smartphone set for end vertebra selection. But reliabilityvalues of manual set were lower than smartphone. Two observers selected signiŞcantly different endvertebra in their repeated selections for manual method.Conclusion: Smartphone-aided method for end vertebra selection and Cobb angle measurement showedexcellent reliability. We can expect a reduction in measurement error rates with the widespread use ofthis method in clinical practice.Level of evidence: Level III, Diagnostic study© 2016 Turkish Association of Orthopaedics and Traumatology. Publishing services by Elsevier B.V. This isan open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).