Sagittal balance of the cervical spine in children older than 4 years: what is the norm?

Abstract

Objective. To search for normal parameters of the sagittal balance of the cervical spine in children, to analyze their dynamics in different periods of childhood, and to compare them with the norm given for the adult population.Material and Methods. To assess the parameters of the sagittal balance of the cervical spine, radiographs were selected that were initially evaluated by radiologists as a variant of the norm. The final sample consisted of 73 radiographs of 44 girls and 29 boys aged 4 to 17 years.Digital radiographs were used to evaluate the 10 most common parameters presented in publications: the angular values of Oc–C2, C2–C7, C7S, Th1S, TIA, NT, CeT, CrT, SCA, as well as the cSVA distance measured in mm. The measurements were carried out independently by 3 specialists working with pediatric patients: an orthopedic surgeon (experience up to 5 years), an orthopedic surgeon (experience more than 15 years), and a radiologist specializing in skeletal pathology (experience more than 5 years). The obtained results weresubjected to statistical processing.Results. Using multivariate analysis of variance, the presence of a statistically significant difference in age was revealed only for cSVA, gender differences were revealed for 6 out of 10 parameters. Most of the parameters showed good and satisfactory agreement between specialists.A very strong correlation was established between the parameters C7S and Th1S, which correlates with the adjacent position of the vertebrae.The C2–C7 and SCA parameters have a strong positive correlation with each other, the CeT parameter is strongly negatively correlated with both of them. The TIA has a strong negative correlation with SCA and a moderate positive correlation with NT, CeT, C7S, and Th1S. The cSVA and CrT values strongly correlate only with each other. Comparison of the obtained parameters of the sagittal balancein children with the data in scientific publications on the adult population revealed statistically significant differences in the values of 6 out of 10 of them.Conclusion. The age norms of the main parameters of the sagittal balance for children, and their gender differences were determined. Their difference from the normal parameters of the adult population was established, which requires that these features be taken into accountin clinical practice.