Purpose This study aimed to establish radiographic standard values for cervical spine morphometry, alignment, and range of motion (ROM) in both male and female in each decade of life between the 3rd and 8th and to elucidate these age-related changes. Methods A total of 1,230 asymptomatic volunteers underwent anteroposterior (AP), lateral, flexion, and extension radiography of the cervical spine. There were at least 100 men and 100 women in each decade of life between the 3rd and 8th. AP diameter of the spinal canal, vertebral body, and disc were measured at each level from the 2nd to 7th cervical vertebra (C2-C7). C2-C7 sagittal alignment and ROM during flexion and extension were calculated using a computer digitizer. Results The AP diameter of the spinal canal was 15.8 ± 1.5 [mean ± standard deviation (SD)] mm at the mid-C5 level, and 15.5 ± 2.0 mm at the C5/6 disc level. The disc height was 5.8 ± 1.3 mm at the C5/6 level, which was the minimum height, and the maximum height was at the C6/7 level. Both the AP diameter of the spinal canal and disc height decreased gradually with increasing age. The C2-C7 sagittal alignment and total ROM were 13.9 ± 12.3°in lordosis and 55.3 ± 16.0°, respectively. The C2-C7 lordotic angle was 8.0 ± 11.8°in the 3rd decade and increased to 19.7 ± 11.3 in the 8th decade, whereas the C2-C7 ROM was 67.7 ± 17.0°in the 3rd decade and decreased to 45.0 ± 12.5 in the 8th decade. The extension ROM decreased more than the flexion ROM, and lordotic alignment progressed with increasing age. There was a significant difference in C2-C7 alignment and ROM between men and women. Conclusions The standard values and age-related changes in cervical anatomy, alignment, and ROM for males and females in each decade between the 3rd and 8th were established. Cervical lordosis in the neutral position develops with aging, while extension ROM decreases gradually. These data will be useful as normal values for the sake of comparison in clinical practice.

Purpose The aim of this study is to establish standard MRI values for the cervical spinal canal, dural tube, and spinal cord, to evaluate age-related changes in healthy subjects, and to assess the prevalence of abnormal findings in asymptomatic subjects. Methods The sagittal diameter of the spinal canal and the sagittal diameter and cross-sectional area of the dural tube and spinal cord were measured on MRIs of 1,211 healthy volunteers. These included at least 100 men and 100 women in each decade of life between the third (20s) and eighth (70s). Abnormal findings such as spinal cord compression and signal changes in the spinal cord were recorded. Results The sagittal diameter of the spinal canal was 11.2 ± 1.4 mm [mean ± standard deviation (SD)]/11.1 ± 1.4 mm (male/female) at the mid-C5 vertebral level, and 9.5 ± 1.8/9.6 ± 1.6 mm at the C5/6 disc level. The crosssectional area of the spinal cord was 78.1 ± 9.4/ 74.4 ± 9.4 mm 2 at the mid-C5 level and 70.6 ± 11.7/ 68.9 ± 11.3 mm 2 at the C5/6 disc level. Both the sagittal diameter and the axial area of the dural tube and spinal cord tended to decrease with increasing age. This tendency was more marked at the level of the intervertebral discs than at the level of the vertebral bodies, especially at the C5/6 intervertebral disc level. The spinal cord occupation rate in the dural tube at the C5 vertebral body level averaged 58.3 ± 7.0%. Spinal cord compression was observed in 64 cases (5.3%) and a T2 high-signal change was observed in 28 cases (2.3%). Conclusions Using MRI data of 1,211 asymptomatic subjects, the standard values for the cervical spinal canal, dural tube, and spinal cord for healthy members of each sex and each decade of life and the age-related changes in these parameters were established. The relatively high prevalence of abnormal MRI findings of the cervical spine in asymptomatic individuals emphasizes the dangers of predicating operative decisions on diagnostic tests without precisely correlating these findings with clinical signs and symptoms.

Standard values of spino-pelvic sagittal alignment were established in each gender and each decade from 20' to 70'. A remarkable change of spino-pelvic sagittal alignment was seen from 7th decade to 8th decade in asymptomatic subjects.

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