Age- and gender-related characteristics of the pubic symphysis and triradiate cartilage in pediatric computed tomography

Abstract

Background: There is little information on the pubic symphysis' normal CT appearance in children.

Objective: We sought to generate age-, gender- and maturity-related symphyseal width appearances in CT scans.

Materials and methods: Pelvic CT scans performed for any reason during a 6-year period in patients younger than 18 years were retrospectively analyzed. The symphysis width was measured in the axial plane and the triradiate cartilage was classified as open or closed.

Results: Four hundred twenty-seven CT scans were evaluated and 350 remained for analysis. Age- and gender-related measurements of the symphysis width are illustrated on various centile graphs. When grouping children by age in years 0-6, 7-11, 12-15 and 16-17, mean (standard deviation) symphysis width was 5.4 mm (0.9), 5.3 mm (1.1), 4.1 mm (1.1) and 3.5 mm (1.0), respectively, in girls and 5.9 mm (1.3), 5.4 mm (1.2), 5.2 mm (1.1) and 4.0 mm (1.0), respectively, in boys. Boys and girls were significantly different in the age groups 12-15 years (P<0.001) and 16-17 years (P=0.04). In the mature pelvis, the symphyseal gap is significantly (P<0.001) shorter in both genders, and in girls compared to boys (P=0.04).

Conclusion: The pubic symphysis width in children differs according to age, gender and maturity. The reference values published herein may help detect symphyseal injury.

Keywords: Children; Computed tomography; Pediatric trauma; Pelvic fracture; Pelvic injury; Pubic symphysis; Triradiate cartilage.