Do Age-Related Variations Of Sagittal Alignment Rely On SpinoPelvic Organization? An Observational Study Of 1540 Subjects

Abstract

Study design Descriptive radiographic analysis of a prospective multi-center database. Objective This study aims to provide normative values of spinopelvic parameters and their correlations according to age and pelvic incidence (PI) of subjects without spinal deformity. Methods After Institutional Review Board (IRB) approval, 1540 full spine radiographs were analyzed. Subjects were divided into 3 groups of PI: low PI < 45°, intermediate PI 45–60°, high PI > 60°, and then stratified by age (20–34, 35–49, 50–64, > 65 Y.O). Pelvic and spinal parameters were measured. Statistical analysis between parameters was performed using Bayesian inference and correlation. Results Mean age was 53.5 years (845 females, 695 males, range 20–93 years). In low PI group, lumbar lordosis (LL) decrease was mainly observed in the 2 younger age groups. In medium and high PI groups, loss of lordosis was linear during aging and occurred mainly on the distal arch of lordosis. Moderate PI group had a stable lordosis apex and thoracolumbar inflection point. High PI group had a stable thoracolumbar inflection point and a more distal lordosis apex in elderly subjects. For all subjects, kyphosis and pelvic tilt (PT) increased with age. There was a constant chain of correlation between PI and age groups. Proximal lumbar lordosis (PLL) was correlated with kyphosis and sagittal vertical axis (SVA C7), while the distal lumbar lordosis (DLL) was correlated with PI and PT. Conclusion This study provides a detailed repository of sagittal spinopelvic parameters normative values with detailed analysis of segmental kyphosis and lordosis distribution according to gender, age, and PI.

Can Lumbopelvic Parameters Be Used to Predict Thoracic Kyphosis at all Ages? A National Cross-Sectional Study

“…Other parameters of the equation also vary over age: LL decreases and PT increases as degenerative changes occur in the lumbar spine, whereas PI also tends to increase in the elderly. [21][22][23] This reflects the typical modifications of sagittal parameters with age, as previously described. 19,[21][22][23][24][25] In a cohort of Japanese adults, average values of sagittal alignment parameters 24 were: 50°± 11 for LL, 54°± 11 for PI, 14°± 8 for PT, and 39°± 8 for SS.…”

“…[21][22][23] This reflects the typical modifications of sagittal parameters with age, as previously described. 19,[21][22][23][24][25] In a cohort of Japanese adults, average values of sagittal alignment parameters 24 were: 50°± 11 for LL, 54°± 11 for PI, 14°± 8 for PT, and 39°± 8 for SS. Our results were similar for SS, PI, PT, LL, whereas TK was higher in our cohort (45°±13 vs 36°± 10).…”

“…Additionally, aging can significantly affect the position of TA also during childhood. 22,29 However, all studies reported a wide range of "physiological" TA. 27,28 Therefore, it seems inappropriate to plan the same TA for all subjects during thoracic spinal surgery.…”

Radiographic patterns and characteristics of sagittal profiles in normal spinopelvic curvatures: An explicit depiction of the distribution of lumbar vertebral bodies and discs

“…Therefore, in the normal population, a greater lordosis contribution of the upper lumbar curve might be associated with a larger PI and SS, and vice versa. The association of PI with proximal lumbar lordosis (PLL) and distal lumbar lordosis (DLL) has become a research interest recent years (Pesenti et al, 2018; Prost et al, 2022). However, there might be a closer correlation between PI and the internal structure in PLL and DLL.…”

Sagittal Alignment in the Degenerative Lumbar Spine

“…Prost et al examined the correlation between age and sagittal alignment of the spine in asymptomatic volunteers 57 . They found that, in individuals with low PI, there was a global decrease in LL in both cephalad and caudal segments; in contrast, in individuals with high PI, more prominent loss of caudal lordosis was associated with increased PT and more prominent loss of cephalad lordosis was associated with increasing kyphosis and positive sagittal malalignment 57 . These findings have important implications and call for thorough assessment of PI and caudal and cephalad lordosis, with a surgical plan that aims to restore appropriate segmental lordosis based on spinopelvic anatomy 58 .…”