Sagittal spinopelvic alignment and psoas muscle thickness in young adults: insights from a cross-sectional CT analysis
Year: 2025
Type: article
Study design: Observational Study
Abstract: Introduction : To ensure optimal alignment between the spine and pelvis, it is essential to understand the sagittal spinal and spinopelvic parameters as well as the interrelationships among these parameters. Aim : The aim is to provide normative values for spinopelvic parameters in healthy adults and to investigate the relationship between psoas muscle thickness index (PMTI) and spinopelvic parameters on whole spine CT imaging. Materials and methods : Pelvic tilt (PT), sacral slope (SS), pelvic incidence (PI), lumbar lordosis (LL), thoracic kyphosis (TK), sagittal vertical axis (SVA), T1-S1 length, L1-S1 length, and psoas muscle thickness (PMT) were measured on whole spine CT, and the PMT/T1-S1 length (mm/m) formula was used to calculate PMTI. PI minus LL (PI−LL) values of the cases were calculated; PI−LL>10 were considered as spinopelvic mismatch, and the cases were compared accordingly. Results : The mean age of the 113 cases was 28.09±6.55 years. The mean values of spinopelvic parameters were as follows: PT: 12.50±6.04, SD: 39.67±7.10, PI: 52.17±8.87, LL: 47.36±9.21, TK: 26.80±6.81, SVA: 36.37±13.26, T1-S1: 463.57±24.82, and L1-S1: 187.97±9.81. LL was correlated with SS and PI ( p <0.001), and SVA with TK and PT ( p <0.001 and p <0.01, respectively). In cases with PI−LL>10, PMTI, PT, and SVA were significantly higher, while SS was significantly lower ( p <0.05, p <0.001, p <0.01, and p <0.01, respectively). Conclusion : This study established normative values for spinopelvic parameters in healthy adults and demonstrated that spinopelvic mismatch is associated with increased psoas muscle thickness index. These findings suggest that compensatory muscle activity in young adults differs from age-related changes observed in degenerative spinal conditions.
Source: Folia Medica
Language: English
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W4415615293