Does the Prevalence of Spondylolysis and Spina Bifida Occulta Observed in Pediatric Patients Remain Stable in Adults?

STUDY DESIGN: Cross sectional study.

OBJECTIVE: To compare the prevalence of lumbar spondylolysis and spina bifida occulta (SBO) in pediatric and adult populations.

SUMMARY OF BACKGROUND DATA: The prevalence of spondylolysis reported from radiograph-based studies in children had been questioned in Computed Tomography (CT)-based studies in adults; however, a recent CT-based study in pediatric patients has confirmed the previously reported data in pediatric populations. SBO, which has been associated with spondylolysis, has demonstrated a decreasing prevalence with increasing age during childhood and adolescence. No studies have compared the prevalence of spondylolysis and SBO in pediatric and adult patients using CT as a screening method.

METHODS: We studied 228 pediatric patients (4 to 15 y old) and 235 adults (30 to 45 y old) who underwent abdominal and pelvic CT scans for reasons not related to the spine. The entire lumbo-sacral spine was evaluated to detect the presence of spondylolysis and SBO. We compared the prevalence of spondylolysis and SBO in pediatric patients and adults.

RESULTS: The prevalence of spondylolysis in pediatric patients was 3.5% (1.1 - 5.9%), and in adults, it was 3.8% (1.7 - 6.8%), P=1. The prevalence of SBO in pediatric subjects was 41.2% (34.8 - 59.2%) and dropped to 7.7%, (4.3 - 11.5%) in adults, P<0.01. The male prevalence of SBO in pediatric patients was 51.4%, while it was 32.2% in females (P<0.01); this gender difference was not significant in the adult population (P=0.8).

CONCLUSIONS: The prevalence of lumbar spondylolysis remained constant from pediatric age through adulthood. The prevalence of SBO decreased from 41.2% in children to 7.7% in adults; this finding suggests that closure of the vertebral arch may not be completed in early childhood in a large percentage of subjects.