Differences in upper body posture between patients with lumbar spine syndrome and healthy individuals under the consideration of sex, age and BMI.

Background: Work-related forced postures, such as prolonged standing work, can lead to complaints in the lower back. Current research suggests that there is increased evidence of associations between patients with low back pain (LBP) and reduced lordosis in the lumbar spine and generally less spinal tilt in the sagittal plane. The aim of this study is to extend the influence of LBP to other parameters of upper body posture in standing, taking into account the rotational and frontal planes.

Methods: The study included a no-LBP group (418 males, 412 females, aged 21-65 years) and an LBP group (138 subjects: 80 females, 58 males, aged 18-86 years) with medically diagnosed lumbar spine syndrome (LSS). The "ABW BodyMapper" back scanner from ABW GmbH in Germany was used for posture assessment using video raster stereography. Statistical analyses employed two-sample t-tests or Wilcoxon-Mann-Whitney-U tests to assess the relationship between the LBP/no-LBP groups and back posture parameters. Linear and logarithmic regressions were used with independent variables including group, sex, height, weight and body mass index (BMI). Significance level: α = 0.05 (95% confidence).

Results: The regression analysis showed that sagittal parameters of the spine (sagittal trunk decline, thoracic and lumbar bending angle, kyphosis and lordosis angles) depend primarily on sex, age, BMI, height and/or weight but not on group membership (LBP/no-LBP). In the shoulder region, a significant dependency between group membership and scapular rotation was found. In the pelvic region, there were only significant dependencies in the transverse plane, particularly between pelvic torsion and BMI, weight, height and between pelvic rotation and group membership, age and sex.

Conclusion: No difference between the patients and healthy controls were found. In addition, sex appears to be the main influencing factor for upper body posture. Other influencing factors such as BMI, height or weight also seem to have a significant influence on upper body posture more frequently than group affiliation.