The Correlation Of The Cervical Alignment With The Thoracolumbopelvic Alignment In Asymptomatic Population Along With Aging

Objective: To evaluate the age-related variations in global spine alignment and the correlation of the cervical alignment with the thoracolumbopelvic alignment in asymptomatic population.Providing a more scientific and reasonable imaging reference for clinical and research work in furture.Methods: Asymptomatic Chinese population were divided into four groups according to different ages(Group A: ≤20 years;Group B: 21-40 years;Group C: 41-60 years;Group D: ≥61 years).Each group was composed of 40 subjects.The following parameters were measured: CBVA,C0-2,C1-2,C2-7 Cobb angle(CA),C1–7 sagittal vertical Axis(C1–7 SVA)、C2–7 sagittal vertical Axis,(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),thoracic kyphosis(TK),lumbar lordosis(LL),Sacral slope(SS),Pelvic tilt(PT),Pelvic incidence(PI),Sagittal vertical axis(SVA),cervical pelvic angle(CPA)and thoracic pelvic angle(TPA).ANOVA and LSD(Least—SignificantDifference)statistical method were used to analyze the differences among four groups,linear regression to analyze independent correlations of the global spine alignment with aging.And association of cervical and cervicothoracic alignment with spinopelvic alignment was analyzed.Results: C1-2 CA,C2-7 CA,C2-7 SVA,NT,TIA,TS,TK,PT,C7 SVA,CPA,TPA were found to gradually increase along with aging(P<0.05).On the contrary,LL and SS gradually decreased with aging(P<0.05).Linear regression analysis revealed that NT,TIA,TS,PT,C7 SVA,CPA and TPA were independently positively correlated with age.TIA was associated with TK,PT and CPA.Conclusion: A gradual increase of cervical and cervicothoracic curvature along with increased thoracic kyphosis was characteristic of the age-related spine in asymptomatic population.Meanwhile,decrease of lumbar lordosis with a retroversional pelvis compensates to maintain the sagittal balance.Cervicothoracic curvature was associated with pelvic retroversion.