Sagittal Standing Posture, Back Pain, and Quality of Life Among Adults From the General Population A Sex-Specific Association

Study Design. A prospective radiographical study of sagittal standing posture among adults consecutively recruited from the general population. Objective. To analyze the relation of suboptimal sagittal standing posture with back pain and health-related quality of life in general adult males and females. Summary of Background Data. Clinical studies have shown the association of sagittal standing posture with pain and reduced quality of life, but this relation has not been assessed in the general adult population. Methods. As part of the EPIPorto population-based study of adults, 178 males and 311 females were evaluated. Age, education, and body mass index were recorded. Radiographical data collection consisted of 36-in. standing sagittal radiographs. Creation of 3 groups for individual spinopelvic parameters was performed (low, intermediate, or high), and 1 of 4 sagittal types of postural patterns attributed to each participant (Roussouly classification). Back pain prevalence and severity were assessed on the basis of self-reported data and health-related quality of life using 2 main components of the 36-Item Short Form Health Survey. Results. In males, differences in back pain severity were observed only among pelvic tilt/pelvic incidence ratio groups. Females presenting high pelvic incidence and sacral slope exhibited higher odds of severe back pain than those with intermediate values (adjusted odds ratios = 2.21 and 2.15; 95% confidence interval, 1.24-3.97 and 1.21-3.86; respectively). Sagittal vertical axis showed the largest differences in physical quality of life of females: high group had 8.8 lower score than the low group (P < 0.001), but this result lost statistical significance after adjustment for age, education, and body mass index. Conclusion. Sagittal standing posture was not consistently associated with quality of life measures in males. Increased pelvic incidence and sacral slope may be involved in causing severe back pain among females. Monitoring sagittal postural parameters has limited usefulness as a screening tool for causes of unspecific musculoskeletal symptoms in the general adult population.