Predictive Value of Serum Vitamin D3 Level for Forearm Fractures among Children in a Tropical Country: A Case Control Study

Introduction: Orthopaedic emergency department commonly receives paediatric fractures, of which forearm fractures constitute a larger proportion with the burden greatest in low-middle income countries. Studies done in the temperate region found an association between forearm fractures in children and low serum vitamin D3. Some studies in our environment have shown low levels of 25-hydroxy vitamin D3 {25(OH)D} in normal Nigerian children, but the association with forearm fractures has not been studied. Aim: To determine if serum vitamin D3 level can predict the occurrence of forearm fractures in children. Materials and Methods: This was a cross-sectional case control study conducted over a year from January 2018 to December 2018 at a tertiary health facility in South-West Nigeria among paediatric patients. Thirty children with forearm fractures and thirty children with no forearm fractures were recruited for the study. Socio-demographic data, mechanisms of fracture, anthropometric measurements and serum 25(OH)D levels were determined. Univariate and multivariate analyses were done for the variables concerning the presence or absence of forearm fractures (dependent variable is the presence or absence of forearm fractures; independent variables include the age, sex, mechanism of injury, outdoor playing time, serum vitamin D3 level). Results: The mean serum 25(OH)D levels in the study group were significantly lower than the controls; (60.751 +/- 15.041 ng/mL and 95.506 +/- 19.489 ng/mL, respectively). There was a statistically significant relationship between the serum level of 25(OH)D and the presence of forearm fracture in children (p=0.002 and OR of 0.838). Conclusion: Children with forearm fracture have relatively lower serum vitamin D3 compared with age matched ones without fracture and they have correspondingly increased odd risks of sustaining fore arm fracture.