Investigation On The Difference Of PI Value Between Age And Gender Among Asymptomatic Population

Objective:To further clarify the difference of pelvic incident angle between different ages and genders in asymptomatic population,and provide reference for spinal sagittal correction.Methods:Collected 250 patients in China-Japan union hospital of Jilin University from December 2012 to December 2018 who met the inclusion criteria.All patients underwent a lateral radiographs of the full length of the spine due to suspecting spinal deformity.Divided into male and female groups according to gender,and then according to age,Divided subgroup of young group,middle age group and old group,collected the full-length lateral radiography of the spine of each patients.PI were was measured at amplifying 5 times by computer system,and the difference between each group was statistically analyzed.Results:The PI values of the young female group,the young male group,the middle-aged female group,the middle-aged male group,the elderly female group,and the old male group were 48.0°±8.0°,47.9°±8.5°,48.1°±6.3°,48.9°± 7.8°,52.8°±6.9°,and 48.2°±7.7°,respectively.The Shapiro-Wick test(S-W test)indicated that the PI values of the patients in each group were consistent with the normal distribution.The ANOVA test found statistically significant difference(P=0.030).After post-hoc tests analysis,the PI value of older women was significantly greater than that of other groups(P<0.05),however,there was no significant difference between the other groups(P>0.05).Conclusion:In the elderly female,the mean pelvic incidence angle increased significantly compared with other groups.Anatomical,biomechanical environment and age-related spine alignment degeneration in the elderly women group result in an increase in PI.In spinal corrected surgery,these differences should be taken into account to reconstruct Optimal spino-pelvic alignment.To achieve optimal surgical outcome and improve patient's quality of life.