The Change Of Cervical Spine Alignment Along With Aging In Asymptomatic Population

Objective:To evaluate the characteristics of cervival spine alignment in different age and to investigate the correlation of Cervical spine alignment changes with aging in asymptomatic population.Providing a more scientific and reasonable imaging reference for clinical and research work in furture.Methods:Asymptomatic population were divided into four groups according to different age(Group A:≤20 years;Group B:21-40years;Group C:41-60years;Group D:≥61years).Each group was composed of 30 subjects.The following parameters were measured: C0-1 Cobb angle,C1-2 Cobb angle,C2-7 Cobb angle,C1-7 sagittal vertical axis(C1-7 SVA),C2-7 SVA,central of gravity to C7 sagittal vertical axis(CG-C7 SVA),Thoracic Inlet Angle(TIA),Neck Tilt(NT),Cervical tilt,Cranial tilt,T1 slope(TS),TS-CL.,ANOVA statistical method was used to analyze the differences among four groups,then linear regression analysis was performed to analyze correlation of the Cervical spine alignment with the aging.Results:C1-7 SVA,C2-7 SVA,CG-C7 SVA,TIA,NT,Cranial tilt and TS were found statistically different among four groups(P<0.01).From Group A to Group D,the mean C1-7 SVA were 30.7mm,26.0mm,21.8mm and 36.9mm,the mean C2-7 SVA were 18.7mm,14.7mm,11.9mm and 24.7mm,the mean CG-C7 SVA were 19.6mm,16.6mm,9.4mm and 26.7mm.The mean TIA were 62.4°,65.0°,71.8° and 76.9°,the mean NT were 39.4°,43.8°,46.3° and 48.2°,the mean Cranial tilt were 5.7°,4.8°,3.0° and 9.5°,the mean TS were 23.0°,21.1°,25.5° and 28.7°.Further linear regression indicated that TIA(r=0.472;P<0.0001),NT(r=0.337;P=0.0006)and TS(r= 0.299;P=0.0025)were positively correlated with aging.Conclusion:A gradual increase of TIA,NT and TS,accompanied with an increased CL is found along with aging in asymptomatic population,among which TIA,NT and TS are significantly correlated with physiological nature of aging.