Normative values of the sagittal lumbopelvic alignment in children during the first decade of life : A retrospective observational study from a German paediatric orthopaedic hospital.

Abstract

Purpose: Normal values for lumbopelvic sagittal alignment in prepubertal non-Asian children have rarely been reported. However, they are becoming increasingly important for treating of hip and spinal disorders in this age group.

Methods: Standing lateral radiographs of the lumbar spine and pelvis of children aged 3-10 years from 2016 to 2024 from a German paediatric orthopaedic hospital with defined inclusion criteria were evaluated in terms of pelvic incidence (PI), lumbar lordosis (LL), pelvic tilt (PT), and sacral slope (SS). The results were compared with those of comparable studies. Parametric and non-parametric statistical tests, as well as linear correlation and regression analyses, were performed according to the characteristics of the variables.

Results: X-rays of 54 children aged 7.8 ± 1.9 years (30 boys, 24 girls, 44 children aged 7-10 years) were included. The mean [± standard deviation (SD)] of LL, PI, PT, and SS were 47.7°±11.2°, 35.8°±7.1°, 5.6°±7.1°, and 30.2°±8.3°, respectively. There were no significant differences between the genders and no age dependencies in our sample. The following significant correlations were observed: PI vs. LL (r = 0.393), PI vs. SS (r = 0.580), PI vs. PT (r = 0.307), SS vs. LL (r = 0.755), SS vs. PT (r=-0.586), and LL vs. PT (r=-0.534). The linear regression analysis yields the following equations: LL = 0.6 PI + 26.35 (R² = 0.155; p = 0.006), PT = 0.31 PI - 5.41 (R² = 0.094; p = 0.024) and SS = 0.68 PI + 5.86 (R² = 0.337; p < 0.001). The measured parameters were not significantly different from those of the Chinese studies, whereas the PI, LL, and SS of the only comparable non-Asian study were significantly higher.

Conclusion: This study adds normal values for lumbopelvic alignment parameters in children aged 3-10 years. Differences and similarities in the parameters and their possible influencing variables between the studies published to date call for further studies, especially with the most likely influencing variables of bone age, percentile curves, body composition, and X-ray technique.