Evaluation of alternative halo ring positions in children using tomography

ABSTRACT

OBJECTIVES: The halo ring can be applied in children, through skeletal traction or a halo vest device, to treat many cervical spine pathologies, including traumatic injuries and pathologies related to deformities. However, the procedure is associated with various complications, such as infection, pin loosening, and respiratory and neurological problems. Although widely studied in adults, the best pin insertion site in children and the correlations of pin insertion sites with outcomes and complications have not been completely elucidated. This study aimed to determine alternative pin placement sites based on a morphological analysis of the infant skull by computerized tomography (CT). METHODS: An analytical-descriptive study was performed using 50 CT scans from children. The Wilcoxon and Friedman tests were used. RESULTS: A linear and directly proportional relation was found between cranial thickness and patient age. The average thicknesses of the anterior points across all ages analyzed ranged from 4.16 mm to 4.98 mm. The thicknesses of the posterior points varied from 3.94 mm to 4.27 mm. Within each age range, points 1 cm above the standard insertion sites had thicknesses similar to those of the standard sites, and points 2 cm above the standard insertion sites had thicknesses greater than those of the standard sites. CONCLUSIONS: The cranial thickness at all points increases linearly with age. Points 1 and 2 cm above the standard insertion sites are viable alternatives for the placement of halo pins. Preoperative CT can aid in choosing the best positioning sites for pins in the skull.