The standing and sitting sagittal spinopelvic alignment of Chinese young and elderly population: does age influence the differences between the two positions?

Differences in Standing and Sitting Spinopelvic Sagittal Alignment for Patients with Posterior Lumbar Fusion: Important Considerations for the Changes of Unfused Adjacent Segments Lordosis

“…The results indicated that in the sitting position, the curvature of lumbar lordosis decreased by 50% and PT increased by 25%. Other studies yielded similar results, which can be summarized as a straightened curve in the lumbar region, pelvic retroversion, and forward displacement of sagittal balance [2][3][4][5]11 . Hey et al compared the spinal sagittal alignment in three weightbearing positions (standing, erect sitting, and natural sitting) in healthy subjects and found that LL decreased by approximately 80% in the natural sitting position; furthermore, the curvature of the trunk was vaguely C-shaped 3 .…”

“…In a previous study, for asymptomatic subjects, it was demonstrated that age signi cantly affected the change in LL when the position was changed from standing to sitting. With increased age, the reduction in LL was smaller 11,17 . In this study, we also found that with increased age, ΔLL and ΔURL were both smaller after lumbar fusion.…”

“…For standing radiographs, the patients were instructed to stand as straight as possible, with the ngers touching the homolateral collar bones 10 . In the erect sitting position, they were asked to ex their hips and knees to 90°, and sit as straight as possible, with the ngers touching the homolateral collar bones 11 . In the natural sitting position, the patients were instructed to sit as naturally as they would on a chair while relaxing the trunk.…”

Sagittal Spinal and Pelvic Alignment in Middle-Aged and Older Men and Women in the Natural and Erect Sitting Positions: A Prospective Study in a Chinese Population

“…Some studies have demonstrated the characteristics of young adults in the standing position and different sitting positions [4,9], but no previous study has reported the normal values for older adults, including middle-aged and older people in different sitting positions. It is inappropriate to base the surgical realignment planning on the results obtained from young adults in the older population, as older people have different sagittal alignment from young adults in both standing and sitting positions, as demonstrated in our previous study and as shown in other studies [13,21,22]. Lack of knowledge of these differences when planning corrective spinal surgery in middle-aged and older adults may lead to non-matched bone alignment and might be responsible for proximal junctional failure [23].…”

“…There have been few studies to compare the erect sitting position and the natural sitting position in the healthy older adults. However, given that older adults have different spinopelvic sagittal alignment compared with young adults in both the standing and sitting positions [10][11][12][13], it may be inappropriate to reconstruct the sagittal alignment of older adults based on the criteria derived from data of young adults [14]. Therefore, this prospective study aimed to compare the sagittal spinopelvic parameters in the erect sitting position and the natural sitting position in healthy middle-aged and older men and women in a Chinese population.…”