Validity and Reliability of Digital Photogrammetry in Determining the Degrees of ‎Thoracic Hyperkyphosis and Lumbar Hyperlordosis in Iranian Adolescent Girls and ‎Boys

Digital imaging method or photogrammetry technique has been considered as an alternative and complementary method of X-ray in posture evaluation by researchers. Therefore, the purpose of this study was to evaluate the validity and reliability of digital photogrammetry in determining the degree of thoracic hyperkyphosis and lumbar hyperlordosis in Iranian adolescent girls and boys.This study was a cross-sectional study with a validity and reliability study design. Subjects were 40 adolescent boys and girls with thoracic hyperkyphosis and lumbar hyperlordosis (age 15.32± 2.57, height 163.17± 9.72, weight 57.32± 7.10). All subjects were referred to the Integrated rehabilitation center of Iranian Red Crescent by a spine specialist for receiving rehabilitations services and were included in the study population based on inclusion criteria. To determine the concurrent validity of the digital photogrammetry method, the measured values were compared with the radiographic images of the subjects to assess the degrees of hyperkyphosis and hyperlordosis curves. Also, to evaluate the reliability of this method, all measurements were compared within 24 to 48 hours after the first imaging.The results showed that digital photogrammetry method had acceptable validity to determine the degree of thoracic hyperkyphosis (p=0.001, r=0.64) and lumbar hyperlordosis (p=0.001, r=0.58) compared to radiography. Also, the photogrammetry method had high inter-rater reliability in determining the degree of thoracic hyperkyphosis (p=0.001, r=0.96) and lumbar hyperlordosis (p=0.001, r=0.87).It seems that the digital photogrammetry method has a valuable validity and reliability for measuring spinal curvatures and specialists can probably use this method to reduce the number of X-rays needed as follow-up in the treatment of those with hyperkyphosis and hyperlordosis abnormalities.