How Is Degenerative Lumbar Scoliosis Associated with Spinopelvic and Lower-Extremity Alignments in the Elderly

Study design: A retrospective cohort study.Purpose: Our aim is to investigate the relationship between degenerative lumbar scoliosis (DLS), and whole-body alignment, including spinopelvic and lower extremity alignments.Overview of literature: DLS is a deformity commonly associated with aging. However, the correlation between whole-body alignment and DLS remains controversial.Methods: Adult volunteers aged over 50 years were included in the study after participating in the screening program. Characteristic data and standing radiographic parameters were assessed. A propensity score model was established with adjustments for age and sex after a preliminary analysis, and cases were divided into DLS (Cobb angle >10 degrees) and non-DLS (Cobb angle <= 10 degrees) groups.Results: There were significant differences in age, sex, C2 sagittal vertical axis (C2-SVA), C7-SVA, T1 pelvic angle (TPA), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), PI minus LL (PI-LL), knee angle, ankle angle, pelvic shift, C7-center sacral vertical line, L4 tilt, femur-tibia angle, and hip-knee-ankle angle (all p <0.05) using a preliminary analysis of 261 cases (75 DLS and 186 non-DLS). A one-to-one propensity score-matched analysis was used after 70 pairs of cases were selected. There were no significant differences in the characteristic data for lower extremity parameters. There were still significantly higher values of C2-SVA, TPA, PI, PT, and PI-LL in DLS group than in non-DLS group (all p <0.05).Conclusions: This study showed an important relationship between DLS and sagittal spinal deformity. However, DLS was not associated with the sagittal and coronal lower extremity alignments.