Fractures in spina bifida from childhood to young adulthood.

Abstract

The aims of this study are to study the prevalence and types of fractures according to age group in spina bifida and examine risk factors associated with fracture. This is a retrospective cohort study of 146 individuals with spina bifida aged 2years or older who attended the paediatric or adult spina bifida multidisciplinary clinic at a single tertiary hospital. Median age at which first fracture occurred was 7years (interquartile range 4-13years). Fracture rates in children (ages 2-10), adolescents (ages 11-18) and adults (age>18) were 10.9/1000 (95% confidence interval 5.9-18.3), 5.4/1000 (95% CI 1.5-13.8) and 2.9/1000 (95% CI 0.6-8.1) patient years respectively. Childhood fractures predominantly involved the distal femur and femoral shaft; these fractures were rarely seen in adulthood. Non-ambulatory status was associated with a 9.8 times higher risk of fracture compared with ambulatory patients (odds ratio 9.8, p=0.016, 95% CI 1.5-63.0). Relative risk of re-fracture was 3.1 (95% CI 1.4-6.8). Urological intervention with intestinal segments was associated with renal calculi (p=0.037) but neither was associated with fracture. The risk of fracture is lower in adults compared with children with spina bifida. The predominant childhood fracture affects the distal femur, and immobility is the most significant risk factor for fracture. Clinical factors contributing to fracture risk need to be elucidated to enable selection of patients who require investigation and treatment of osteoporosis.