Abstract:Objective To explore the difference of sagittal spino-pelvic parameters at different age stages and the changes with age in Eastern China. Methods The medical records of 311 asymptomatic healthy volunteers from Jan. 2014 to Aug. 2015 in Physical Examination Center of our hospital were retrospectively analyzed. The demographic data and radiological parameters were collected by two individual surgeons, including age, gender, maximum thoracic kyphosis (maxTK), maximum lumbar lordosis (maxLL), maxLL minus maxTK (maxLL-maxTK), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), PT/SS, PI minus lumbar lordosis (PI-LL), sagittal vertical axis (SVA), T1 sagittal angle, T1 pelvic angle (TPA) and T1 spinopelvic inclination (T1SPI). Pearson correlation analysis was performed to evaluate the relationship between age and sagittal spino-pelvic parameters. A multiple linear regression equation was established to analyze the relationship between age and maxTK. The volunteers were divided into seven groups (<20 years, ≥ 20 and <30 years, ≥ 30 and <40 years, ≥ 40 and <50 years, ≥ 50 and <60 years, ≥ 60 and <70 years, and ≥ 70 years), and the sagittal spino-pelvic parameters were compared using Kruskal-Wallis H test. Results In 311 healthy volunteers, the maxTK (r=0.280, P<0.01), maxLL-maxTK (r=-0.320, P<0.01), SS (r=-0.216, P<0.01), PT (r=0.237, P<0.01), PT/SS (r=0.282, P<0.01), SVA (r=0.279, P<0.01), T 1 sagittal angle (r=0.247, P<0.01) and TPA (r=0.259, P<0.01) were all related to age, while the maxLL, PI, PI-LL, and T1SPI were not related to age (all P>0.05). According to the established multiple linear regression equation:maxTK=0.175×age+28.233, the maxTK increased by 1.75° every 10 years of age. There were 8, 56, 51, 59, 56, 56 and 25 volunteers in the groups of <20 years, ≥ 20 and <30 years, ≥ 30 and <40 years, ≥ 40 and <50 years, ≥ 50 and <60 years, ≥ 60 and <70 years, and ≥ 70 years, respectively. The maxTK, PT, PT/SS, SVA, T1 sagittal angle and TPA were significantly increased with age (all P<0.01), and the maxLL-maxTK and SS were significantly decreased with age (P<0.01, P<0.05). Conclusion In asymptomatic population of Eastern China, maxTK is increased with age (1.75° per 10 years old).