Vitamin D Levels and Patients with Metatarsal Fractures

Abstract

Category: Midfoot/Forefoot. Introduction/Purpose: Deficiency of vitamin D has been associated with a range of diseases, with hypovitaminosis D affect approximately 1 billion people worldwide. Among orthopaedic patients, insufficiency has been reported between 43% and 78%. Currently, the orthopaedic literature has conflicting evidence to associate vitamin D deficiency with acute fractures, stress fractures and nonunions. Furthermore, there is limited literature on vitamin D and its effects in foot and ankle patients. The purpose of this study is to determine the prevalence of vitamin D insufficiency in patients who have sustained low energy metatarsal fractures compared to non-osseous foot and ankle sprains. Methods: Data collection occurred from May 2012 to August 2014. Patients with low-energy closed metatarsal fractures or non-osseous ankle sprains, between 18 and 85 years old, were enrolled. Patient demographics for fracture and sprain groups were collected through chart review and included age (subdivided into categories: 18-54, 55-65, and >65), gender, race, BMI, mechanism of injury, smoking status, history of fractures, osteoporosis or osteopenia and a previous diagnosis of vitamin D deficiency were also noted. Sufficient, insufficient and deficient levels of vitamin D were defined as ≥ 30ng/ml, 20-30ng/ml, and 65 years old (p=0.01), non-Hispanic/white race (p=0.05) and a BMI < 30 (p=0.01). None of these characteristics independently predicted fracture risk, though the correlation with age may be explained by increased supplement use. Conclusion: There was no difference in the mean vitamin D level or incidence of vitamin D insufficiency between patients with metatarsal fractures versus sprains. No causal relationship was established between serum vitamin D levels and fractures. There was, however, an association found between higher vitamin D levels and vitamin D supplementation, white race and lower BMI. This is one of the first studies in the foot and ankle literature to find no association between vitamin D levels and risk fractures, demonstrating need for further study of the relationship between vitamin D deficiency and different types of fractures.